New Year's Eve is upon us, and I just want to wish all of you a happy New Year. I don't know about you, but I'm about sick of the "2018 in review" shows on TV, so I'll just post a little about my year in review.
2018 was my third full year of retirement. The important things in life were all good - all stable. Although family is smaller than it was a few years ago, we lost no one. No one in the family had major medical issues. I helped my big brother make some positive impacts on his diabetes, dropping his diabetic markers closer to the normal range, which probably makes me feel better than it does him. We lost a friend, and others were and are hospitalized. It makes you appreciate every day all the more. An old joke has come true. Every now and then I think I'd like to go to work, but if I lie down for a while that thought goes away.
Retirement is a relatively new concept in society, at best a couple of
hundred years old, and it's evident that society (in some sort of
nebulous, society-at-large sense) is having troubles with it. See "underfunded pension plans" with your favorite search engine. Whenever someone asks me how I like retirement, I tend to say, "I recommend it to everyone". It does take a little getting used to, but all changes in life do.
Regular readers will know that my shop time for the first half of the year was mostly spent on my Philip Duclos Fire Eater Engine, starting not long after that February 17 posting and finishing at the end of September. I've only run it a few times after than video and never took pictures of it. After that, I got started on a few projects to make things better, and I'm more or less sequencing through them. Of course, I've posted lots on the CNC Threading - including yesterday - and I have the lumber to build the new front for my mill enclosure. That wood has been sitting for weeks.
Although I can and might change plans before then, my next build is likely to be what's called a Webster engine, an internal combustion, one cylinder, model engine that was designed by a guy named Joe Webster. Joe graciously released his plans to the hobby modeling community. This is a screen capture from one video, by a YouTuber calling himself PatPending. The exact way these are built varies, as you can tell by searching YouTube for the Webster engine builds, but the plans are available for download and I'm likely to go by the plans. Unless something looks really cool. Or another project grabs my attention.
There have been regular intervals of time off to fix things around the house. I've written about some of them, like "vacuum cleaner day" and about my odd problem with a ground fault indicator that kept tripping for no apparent reason. That hadn't tripped since about late September when I took a couple of surge protected power strips out. I went to non-protected strips but put one of the "pulled ones" back in service earlier in the month when I needed an outlet strip with a longer power cord and that same GFI has tripped twice in the weeks since. The first time was 12/20, in a period when we had lots of rain. The other time was Christmas; more precisely sometime between Christmas Eve around evening when I shut down the shop and the day after Christmas when I went back into the shop. No rain, no cold, if anything it was too darn hot for that two day period. That makes me think that this particular surge protected strip might be the culprit.
I wish you all a happy, prosperous, safe and free New Year! Remember, if you drink, don't text and if you text, don't drive. Or something like that.
In the World of the High Tech Redneck, the Graybeard is the old guy who earned his gray by making all the mistakes, and tries to keep the young 'uns from repeating them. Silicon Graybeard is my term for an old hardware engineer; a circuit designer. The focus of this blog is on doing things, from radio to home machine shops and making all kinds of things, along with comments from a retired radio engineer, that run from tech, science or space news to economics; from firearms to world events.
Monday, December 31, 2018
Sunday, December 30, 2018
CNC Lathe Threading Progress
On my last post about efforts to get this perfected, back on the 19th, I showed some completed threads and said there was more I wanted to do besides the threading, but that the threading portion was almost done. Among those things was to put a few turns of a fine pitch thread on a piece, like some of the parts I had to make for the flame eater engine. I did that on 21st. This pic shows that short aluminum piece (from 12/21) alongside a longer cold rolled steel piece cut manually (by changing gears on the lathe) back over the summer. Call that five turns of 4-40 threads, 1/8" long, on a the end of a stud that's 3/16" long.
So that major goal was accomplished, and to be honest that's probably the sort of threading I'm going to be doing.
In that last post I had commented on how ratty the 10-32 threads looked. I did a second, longer piece and it came out pretty ratty looking, too. This montage shows the one from the last post, in aluminum, and the second one in brass.
If you look to the left of the nut in that top picture, you can see that one thread looks like it's cutoff along the mid-line. Pretty much all of the threads on the left are misshapen. Same thing with the one on the bottom, cut in brass the next day. On this one you can vividly see what looks like at least a couple of different cuts going on. Fixing this became the focus of my troubleshooting.
Along the way, I found that my CNC control program, Mach3 does not adjust its feed rate during a pass. It samples the rotation speed (RPM) from my sensor just before it starts a cutting pass, calculates how fast to move the cutter and then does that. The effect of that is that the errors would show up like this: the longer the cut, the more inches vary when you're setting inches/minute. I noticed when I was first putting together the optical sensor that the speed did wander. On my oscilloscope, it looked like jitter in the pulses: some wider (slower RPMs) and some narrower (higher RPMs). I couldn't see a way to regulate the motor's speed any better, but I do have a manual lathe that uses the same headstock, so I did a head transplant. The RPM variation got smaller.
Time for another sample.
If you look at the left end of this piece compared to those two above, the difference in the thread quality is night and day. A commercial nut was a little tough to get started but threaded on and fit great after the first quarter inch of thread (the threaded length is either 0.6 or 5/8" long - I forget).
But we're not exactly out of the woods yet, either. Compare the left end threads to the right end threads. The right end threads are flat across the top and not as deeply Vee shaped. What could be causing that?
All cutting produces enough force to deform metal away from the cutter, and that piece is long in terms of length to diameter ratio, just over 3:1. I tried a couple of ways I have to support the end of the rod, a live center and a dead center. The live center spins on ball bearings while a dead center is just a tapered, pointed piece of steel that rests in divot in the end of the screw and keeps it from moving sideways as much. The live center was too big in diameter and the cutter hit it. The dead center would fit, but was too short to reach the screw. I had no way to support the screw while cutting.
A way to remove this sort of variation in a straight cylinder you've cut on the lathe is to do a "spring pass" you move the cutter back across the piece and it cuts off (most) of the metal that acted like a spring and compressed under the cutter the first time. I had been cutting the screw with two spring passes. Today, I increased it to 10 and watched closely under magnifiers. Sure enough, I could see the screw bending away from the cutter when it was at the right end of the screw. As the machine went through the spring cuts, I could see it take more metal from the right end than the left.
This one is a bit more subtle but if you compare the right ends of this screw and the previous one, you can see that only the first couple of threads look flat topped. Sure enough, the commercial nut goes on with a little difficulty on the first couple of turns and then feels pretty normal.
What to do? I suppose the straight forward solution is to get or make a longer center to try to lock the end of the screw in place while I cut. Perhaps I do even more spring passes. Twice as many as threading cuts? Either way, this is much closer to Done. It's not relevant for the kind of pieces I was thinking of when I thought of moving threading from the gear-driven setup to "software defined gears", but with the capability of cutting virtually any thread, there's no reason not to make it as good as possible.
So that major goal was accomplished, and to be honest that's probably the sort of threading I'm going to be doing.
In that last post I had commented on how ratty the 10-32 threads looked. I did a second, longer piece and it came out pretty ratty looking, too. This montage shows the one from the last post, in aluminum, and the second one in brass.
If you look to the left of the nut in that top picture, you can see that one thread looks like it's cutoff along the mid-line. Pretty much all of the threads on the left are misshapen. Same thing with the one on the bottom, cut in brass the next day. On this one you can vividly see what looks like at least a couple of different cuts going on. Fixing this became the focus of my troubleshooting.
Along the way, I found that my CNC control program, Mach3 does not adjust its feed rate during a pass. It samples the rotation speed (RPM) from my sensor just before it starts a cutting pass, calculates how fast to move the cutter and then does that. The effect of that is that the errors would show up like this: the longer the cut, the more inches vary when you're setting inches/minute. I noticed when I was first putting together the optical sensor that the speed did wander. On my oscilloscope, it looked like jitter in the pulses: some wider (slower RPMs) and some narrower (higher RPMs). I couldn't see a way to regulate the motor's speed any better, but I do have a manual lathe that uses the same headstock, so I did a head transplant. The RPM variation got smaller.
Time for another sample.
If you look at the left end of this piece compared to those two above, the difference in the thread quality is night and day. A commercial nut was a little tough to get started but threaded on and fit great after the first quarter inch of thread (the threaded length is either 0.6 or 5/8" long - I forget).
But we're not exactly out of the woods yet, either. Compare the left end threads to the right end threads. The right end threads are flat across the top and not as deeply Vee shaped. What could be causing that?
All cutting produces enough force to deform metal away from the cutter, and that piece is long in terms of length to diameter ratio, just over 3:1. I tried a couple of ways I have to support the end of the rod, a live center and a dead center. The live center spins on ball bearings while a dead center is just a tapered, pointed piece of steel that rests in divot in the end of the screw and keeps it from moving sideways as much. The live center was too big in diameter and the cutter hit it. The dead center would fit, but was too short to reach the screw. I had no way to support the screw while cutting.
A way to remove this sort of variation in a straight cylinder you've cut on the lathe is to do a "spring pass" you move the cutter back across the piece and it cuts off (most) of the metal that acted like a spring and compressed under the cutter the first time. I had been cutting the screw with two spring passes. Today, I increased it to 10 and watched closely under magnifiers. Sure enough, I could see the screw bending away from the cutter when it was at the right end of the screw. As the machine went through the spring cuts, I could see it take more metal from the right end than the left.
This one is a bit more subtle but if you compare the right ends of this screw and the previous one, you can see that only the first couple of threads look flat topped. Sure enough, the commercial nut goes on with a little difficulty on the first couple of turns and then feels pretty normal.
What to do? I suppose the straight forward solution is to get or make a longer center to try to lock the end of the screw in place while I cut. Perhaps I do even more spring passes. Twice as many as threading cuts? Either way, this is much closer to Done. It's not relevant for the kind of pieces I was thinking of when I thought of moving threading from the gear-driven setup to "software defined gears", but with the capability of cutting virtually any thread, there's no reason not to make it as good as possible.
Saturday, December 29, 2018
Ooooohhh - Talk Tax Rates To Me, Baby
In an academic, partially removed-from-reality sense.
I found an interesting article this week from Daniel J Mitchell's blog International Liberty. The article, posted December 18th, concerns the damages that increased marginal tax rates cause. The article, World Bank Study Confirms the Ever-Increasing Damage of Ever-Increasing Tax Rates, begins by discussing the concept of deadweight loss, which shows the portion of the market for a product that gets lost because of taxes. There's an excellent video here that explains this chart (it's a graphic they develop).
The thing to bear in mind is that the deadweight loss from the tax removes the entire area in gray. That economic activity never happens. The government tries to just skim some tax revenue off transactions going on, but instead government reduces the economic activity. How many times have you heard that the revenue from a new tax is less than what was predicted? On transactions that happen, they're a guaranteed winner, but they get nothing from the economic activity that they cut off.
Now mentally reduce the tax rate. That makes the purple box shorter from top to bottom. That, in turn allows the right end of the box to extend farther to the right before it simultaneously intersects the supply and demand curves, reducing the deadweight loss. Conclusion: Lower taxes allow more economic activity. Now mentally increase the tax rate, making the box taller and bringing the intersection back to the left. Conclusion: higher taxes allow less economic activity.
Less obvious is that the curves don't move linearly. That is, if you double the tax rate, you don't necessarily double the revenue. You increase the amount of deadweight loss which could cut off sales completely, or more than likely create black market ways to avoid the taxes. As Mitchell says:
Final words to Daniel J Mitchell:
I found an interesting article this week from Daniel J Mitchell's blog International Liberty. The article, posted December 18th, concerns the damages that increased marginal tax rates cause. The article, World Bank Study Confirms the Ever-Increasing Damage of Ever-Increasing Tax Rates, begins by discussing the concept of deadweight loss, which shows the portion of the market for a product that gets lost because of taxes. There's an excellent video here that explains this chart (it's a graphic they develop).
The thing to bear in mind is that the deadweight loss from the tax removes the entire area in gray. That economic activity never happens. The government tries to just skim some tax revenue off transactions going on, but instead government reduces the economic activity. How many times have you heard that the revenue from a new tax is less than what was predicted? On transactions that happen, they're a guaranteed winner, but they get nothing from the economic activity that they cut off.
Now mentally reduce the tax rate. That makes the purple box shorter from top to bottom. That, in turn allows the right end of the box to extend farther to the right before it simultaneously intersects the supply and demand curves, reducing the deadweight loss. Conclusion: Lower taxes allow more economic activity. Now mentally increase the tax rate, making the box taller and bringing the intersection back to the left. Conclusion: higher taxes allow less economic activity.
Less obvious is that the curves don't move linearly. That is, if you double the tax rate, you don't necessarily double the revenue. You increase the amount of deadweight loss which could cut off sales completely, or more than likely create black market ways to avoid the taxes. As Mitchell says:
Simply stated, if a tax of X does Y amount of damage, then a tax of 2X will do a lot more damage than 2Y.Given this, it's interesting to see supporting evidence from the World Bank (of all places) published this month.
This is the core economic reason why even left-leaning international bureaucracies agree that class-warfare taxes are so destructive. When you take a high tax rate and make it even higher, the damage grows exponentially.
…studies have used the narrative approach for individual or multi-country analyses (in all cases, focusing solely on industrial economies, and mostly on industrial European countries). These studies find large negative tax multipliers, ranging between 2 and 5. This recent consensus pointing to large negative tax multipliers, especially in industrial European countries, naturally entails important policy prescriptions. For example, as part of a more comprehensive series of papers focusing on spending and tax multipliers, Alesina, Favero, and Giavazzi (2015) point that policies based upon spending cuts are much less costly in terms of short run output losses than tax based adjustments.The World Bank study showed that VAT taxes were more destructive to developing economies than to established economies, BUT that the deadweight loss was greater in the established countries because the initial tax burden was higher; in other words, "they already had big gray boxes". The World Bank authors include this pair of data plots from trying to determine how much raising VAT rates affect the incentives to work (left) and incentives to invest. It shouldn't be a surprise the raising taxes reduced both the incentives to work and to invest.
A natural question is whether large negative tax multipliers are a robust empirical regularity… In order to answer this highly relevant academic and policy question, one would ideally need to conduct a study using a more global sample including industrial and, particularly, developing countries. …This paper takes on this challenge by focusing on 51 countries (21 industrial and 30 developing) for the period 1970-2014. …we focus our efforts on building a new series for quarterly standard value-added tax rates (henceforth VAT rates). …We identify a total of 96 VAT rate changes in 35 countries (18 industrial and 17 developing).
Final words to Daniel J Mitchell:
The moral of the story is that all tax increases are misguided, but class-warfare taxes wreak the most economic havoc.
P.S. Not everyone understands this common-sense observation. For instance, the bureaucrats at the Congressional Budget Office basically argued back in 2010 that a 100 percent tax rate was the way to maximize growth.
Friday, December 28, 2018
Aquaman
Perhaps the most hyped movie of this mid-winter movie season has been Aquaman, the latest in the DC Universe. Aquaman appeared in last Spring's Justice League and introduced in the previous year's Batman v Superman: Dawn of Justice. It opened in the US last Friday after a very big week overseas, essentially covering the costs of making the movie about 3 times. 'Tis the season to be busy and all, so Mrs. Graybeard and I got to our local cineplex yesterday for the 1:00 matinee to check it out.
Much like these movies have tended to do, the first official trailer dropped five months ago in July, and hints at the visual spectacle that the movie really is. It really is a visual feast; the vast majority is supposed to be in several underwater nations inhabited by water breathing humans with abilities far beyond what "surface dwellers" have.
The story is, well, a stereotypical kid's book story like others you've heard many times before. Call it the out of place, nerdy kid who's unknowingly the heir to an all-important throne. Arthur Curry is a half breed: his father was a lighthouse keeper and his mother the soon-to-be Queen Atlanna of Atlantis who runs away from her arranged marriage and goes ashore. His mother, (Nicole Kidman), tells him as he's growing up that he could be the "chosen one" to unify the surface dwellers and the undersea world.
Much like these movies have tended to do, the first official trailer dropped five months ago in July, and hints at the visual spectacle that the movie really is. It really is a visual feast; the vast majority is supposed to be in several underwater nations inhabited by water breathing humans with abilities far beyond what "surface dwellers" have.
The story is, well, a stereotypical kid's book story like others you've heard many times before. Call it the out of place, nerdy kid who's unknowingly the heir to an all-important throne. Arthur Curry is a half breed: his father was a lighthouse keeper and his mother the soon-to-be Queen Atlanna of Atlantis who runs away from her arranged marriage and goes ashore. His mother, (Nicole Kidman), tells him as he's growing up that he could be the "chosen one" to unify the surface dwellers and the undersea world.
When the story is kind of a trope story, you need likable characters you want to watch.
Aquaman (Jason Momoa) does good brooding looks and good fight scenes (which seems to be
what they want from him) but doesn't do much for the quieter scenes. The female lead, Mera (Amber Heard), was better at a wider range of emotions and you can watch her change as the movie goes along, getting more drawn to Arthur. The other principal characters, such as Arthur's half-brother, King Orm, his trainer Vulko, and King Nereus, were kind of
one-dimensional backgrounds - almost NPC to use that new term. So you need exciting visuals to keep your attention. Like mounted Atlantean troops on sharks.
(Photo courtesy of Warner Bros. Pictures here, but you knew I didn't put that together myself to claim it as my work).
The movie was honestly pretty average. Spectacular CGI visuals,
but otherwise kind of "meh". On IMDB, their audience rating is about 75% and
that's about where I come down. I can't say I was looking at my watch
the whole time but I sure wasn't lost in the fun. One thing I found annoying was that the Atlanteans and other underwater nations were going to wage war on the surface dwellers for pollution and "crimes against the sea" (my words not theirs). Sorry, but that trope is worn out, too.
Maybe
I'm becoming immune to superhero movies. Or, God forbid, developing
higher standards. But wait! Captain Marvel is due out in March!
That'll be here before we know it. This summer we get Godzilla: King of the Monsters, a "classic" (formulaic) Godzilla vs. Mothra and all the
other monsters from those Grade B Japanese flicks of the 60s. The link
between the Marvel and Godzilla universes is that in the King Kong movie
from '17, Kong: Skull Island (which is part of an 8 year story arc to this summer's Godzilla movie and a Godzilla vs. Kong movie in two years), the mandatory pretty girl was Brie Larson
who is going to be Captain Marvel. She played opposite Tom Hiddleston
and Samuel L Jackson, who play Loki and Nick Fury from the Marvel
movies. Coincidence?
Director James Wan (the guy with this hands up) working with Amber Heard, Jason Momoa and Willem Dafoe in a scene supposed to be in "air bubble" deep underwater. One thing I think James Wan got right was that he let their hair look wet and bedraggled, as if they just got out of the water, instead of having everyone look like they spent a half day in high end hair salon.
Thursday, December 27, 2018
A Different Look at the Drone Problem
Several of us bloggers have addressed the problems that remotely controlled aerial drones are bringing, with most of the conversation about hobbyist-level nano drones. Peter Grant at Bayou Renaissance Man (for example) has been sounding the alarm on this for quite a while and others have talked about it, too. I haven't done much.
Much of this was academic discussion until the Gatwick airport service disruption last week. Drones flying over the airfield interrupted schedules on Wednesday and Thursday, affecting 120,000 people. John Robb at Global Guerrillas posted on this, giving details on the disruption and drawing the lessons that people dedicated to causing chaos and disruption get out of the event.
I had an email last Friday asking if I thought it was possible to jam the drones and take them down. I said that when the dust settled from Christmas that I'd take a deeper look but that yes, as a general rule, any radio link can be jammed if you're willing to spend enough resources. If you're in charge of protecting a major airport, you should be spending that. On the other hand, if you want to disrupt the airport while making your drones jam resistant, there are very likely ways around the jamming.
The types of drones and their characteristics.
Jam resistance is achieved by using modulation modes that are less susceptible to jamming. For example, conventional FM is easy to jam over a limited area by putting a signal on the transmitter's frequency. I worked in an engineering lab once where one of the engineers hated another guy's favorite type of music. Every day at lunch, he would tune a signal generator to the FM broadcaster's frequency, put a short wire antenna in the output connector and turn up the generator's output. FM has what's called a "capture effect" where the stronger signal dominates the audio output and the unmodulated carrier from the signal generator silenced the audio output of the other guy's radio.
Likewise, if you're using a narrowband FM walkie talkie, a strong radio carrier on frequency can render FRS or amateur FM HT comm systems useless.
AM behaves differently and both the jammer and desired signal show up in the audio. All the signal generator could do is reduce the output audio volume. More advanced modulation techniques, broadly called spread spectrum, are more resistant to jamming. (Spread spectrum is when the signal's spectrum is much wider than the bandwidth needed to carry the information) Making your signal jam resistant has a good analogy to making a house more secure. You can do things to harden your home, but a determined attacker can still get it. You can spend more money and make it harder to get in, but you haven't made it impossible to get in, just much harder. Likewise, an attacker determined to spend any amount to make a signal jam resistant has a better chance than someone who can't spend very much. Cheap consumer electronics isn't going to be as jam resistant as military systems.
What I needed to find was the methods the nano drone market uses. It turns out, one of the test equipment and instrumentation giants in electronics, Rohde & Schwarz, published a white paper you can read online or download (pdf warning) with just this sort of information. This chart is a good summary.
The implications from the chart are that cheap hobby drones are most likely to use the 2.4 GHz ISM band (Industrial, Scientific, Medical) - better known as the WiFi band. They use Frequency Hopping Spread Spectrum (FHSS) or Direct Sequence Spread Spectrum (DSSS). FHSS is sending the information spread over different channels and then the channels are "reassembled" in the receiver. DSSS spreads the information across both frequency and time. (explanation) FHSS WiFi is fairly easy to jam, and cheap WiFi jammers are widely available - cheaper than a low end cellphone.
It implies that something that transmitted noise in the 2.4 GHz ISM band could jam the drones. It would also jam every WiFi link in the area. That would not be popular.
There's a bigger problem. What if the drone is not being controlled by some dork in the weeds at the end of the runway, but it's flying a GPS path programmed into it? Hobby drones can do that. Besides that, what if the drone is being flown by that dork and then you jam it. Then what happens? Does it land because it's no longer getting commands or does it have the GPS coordinates it took off from and now goes back to them? Going back along the line of flight would be a good safety procedure; assuming the drone has lost the signal simply because it went too far, have it fly back where it last had a useful signal. GPS can be jammed. That would cause the drone to be lost and perhaps land but jamming GPS would cause a major impact in the area.
Just because you jammed the signal doesn't mean your problems are over. Besides, if the drone operator is really trying to get their payload past whatever you can do, perhaps they could just change the radios to something they can get that isn't as likely to be jammed. The more non-standard it is, the better. That table says 5 GHz WiFi is used on drones - so it's too common.
Because of problems like this, there's an emerging and apparently fast growing industry in anti-drone technologies. Different technologies are being featured in a "dog fight" over who gets market share. Aside from that Rohde-Schwarz paper, Skydroner out of Singapore and Droneshield of Australia are examples of companies emphasizing physical security for your factory or other facilities.
Low cost drones are becoming a real security concern - during Trump's inauguration, the FAA closed the air space over DC, including closing to drones. There's no reason to think "drone free zones" work any better than gun free zones.
Much of this was academic discussion until the Gatwick airport service disruption last week. Drones flying over the airfield interrupted schedules on Wednesday and Thursday, affecting 120,000 people. John Robb at Global Guerrillas posted on this, giving details on the disruption and drawing the lessons that people dedicated to causing chaos and disruption get out of the event.
I had an email last Friday asking if I thought it was possible to jam the drones and take them down. I said that when the dust settled from Christmas that I'd take a deeper look but that yes, as a general rule, any radio link can be jammed if you're willing to spend enough resources. If you're in charge of protecting a major airport, you should be spending that. On the other hand, if you want to disrupt the airport while making your drones jam resistant, there are very likely ways around the jamming.
The types of drones and their characteristics.
Jam resistance is achieved by using modulation modes that are less susceptible to jamming. For example, conventional FM is easy to jam over a limited area by putting a signal on the transmitter's frequency. I worked in an engineering lab once where one of the engineers hated another guy's favorite type of music. Every day at lunch, he would tune a signal generator to the FM broadcaster's frequency, put a short wire antenna in the output connector and turn up the generator's output. FM has what's called a "capture effect" where the stronger signal dominates the audio output and the unmodulated carrier from the signal generator silenced the audio output of the other guy's radio.
Likewise, if you're using a narrowband FM walkie talkie, a strong radio carrier on frequency can render FRS or amateur FM HT comm systems useless.
AM behaves differently and both the jammer and desired signal show up in the audio. All the signal generator could do is reduce the output audio volume. More advanced modulation techniques, broadly called spread spectrum, are more resistant to jamming. (Spread spectrum is when the signal's spectrum is much wider than the bandwidth needed to carry the information) Making your signal jam resistant has a good analogy to making a house more secure. You can do things to harden your home, but a determined attacker can still get it. You can spend more money and make it harder to get in, but you haven't made it impossible to get in, just much harder. Likewise, an attacker determined to spend any amount to make a signal jam resistant has a better chance than someone who can't spend very much. Cheap consumer electronics isn't going to be as jam resistant as military systems.
What I needed to find was the methods the nano drone market uses. It turns out, one of the test equipment and instrumentation giants in electronics, Rohde & Schwarz, published a white paper you can read online or download (pdf warning) with just this sort of information. This chart is a good summary.
The implications from the chart are that cheap hobby drones are most likely to use the 2.4 GHz ISM band (Industrial, Scientific, Medical) - better known as the WiFi band. They use Frequency Hopping Spread Spectrum (FHSS) or Direct Sequence Spread Spectrum (DSSS). FHSS is sending the information spread over different channels and then the channels are "reassembled" in the receiver. DSSS spreads the information across both frequency and time. (explanation) FHSS WiFi is fairly easy to jam, and cheap WiFi jammers are widely available - cheaper than a low end cellphone.
It implies that something that transmitted noise in the 2.4 GHz ISM band could jam the drones. It would also jam every WiFi link in the area. That would not be popular.
There's a bigger problem. What if the drone is not being controlled by some dork in the weeds at the end of the runway, but it's flying a GPS path programmed into it? Hobby drones can do that. Besides that, what if the drone is being flown by that dork and then you jam it. Then what happens? Does it land because it's no longer getting commands or does it have the GPS coordinates it took off from and now goes back to them? Going back along the line of flight would be a good safety procedure; assuming the drone has lost the signal simply because it went too far, have it fly back where it last had a useful signal. GPS can be jammed. That would cause the drone to be lost and perhaps land but jamming GPS would cause a major impact in the area.
Just because you jammed the signal doesn't mean your problems are over. Besides, if the drone operator is really trying to get their payload past whatever you can do, perhaps they could just change the radios to something they can get that isn't as likely to be jammed. The more non-standard it is, the better. That table says 5 GHz WiFi is used on drones - so it's too common.
Because of problems like this, there's an emerging and apparently fast growing industry in anti-drone technologies. Different technologies are being featured in a "dog fight" over who gets market share. Aside from that Rohde-Schwarz paper, Skydroner out of Singapore and Droneshield of Australia are examples of companies emphasizing physical security for your factory or other facilities.
Low cost drones are becoming a real security concern - during Trump's inauguration, the FAA closed the air space over DC, including closing to drones. There's no reason to think "drone free zones" work any better than gun free zones.
Wednesday, December 26, 2018
I Think the Fed Might Actually Be Doing Something Right
I know, right? The detested, execrable Federal Reserve doing something right? Even more bizarre, I'm agreeing with the Fed? I've probably beaten on the Federal Reserve as much as or more than any blogger you know in my eight years here, so the fact I'm kind of agreeing with them surprises me more than you.
Here, I turn to John Mauldin of Mauldin Economics.
I disapprove of there even being a Federal Reserve Bank, with all the implications of a centrally controlled economy it brings, but for the moment the best we can do is hope to minimize the harm it does. They need to raise interest rates and crank back in the trillions of dollars worth of funny money they created during the Obamanation. Rates were so low for so long, and so much excess money was created that if another recession were to start soon, they'd be left with no tricks. They'd be in a shootout holding an empty magazine. Just a couple of short years ago, Janet Yellen was proposing (we hear) using negative interest rates to get people to spend and kick start the economy. That's the kind ofhocus pocus they'd pull out of their asses advanced monetary policy they'd implement in the event of another recession.
Here, I turn to John Mauldin of Mauldin Economics.
The last three Federal Reserve Chairs have acted like the Fed has three mandates: the two official ones (low inflation and full employment) and an unofficial third one: making sure asset prices rise as the market wants. Not just the stock market, but real estate and all other investment assets. It started with the Greenspan “Put” which morphed into the Bernanke Put (remember the taper tantrum?) and reached its apex with the Yellen Put.And what did we get? Bubbles. It's arguable that every boom and bust cycle in the last 105 years was caused by the monetary manipulations of the Federal Reserve. I'm currently reading an expansive view of that called "The Skyscraper Curse" and will have more to say as I read more ('tis the season to be busy and that has constrained reading time a bit).
Jerome Powell, the current Fed Head, seems to be acting as though he considers only the two official duties as his responsibility. That probably has a lot to do with stock markets' bleeding off the last 15 months worth of growth in asset prices since the start of December.
- As Stan Druckenmiller says, the really big Fed mistake was when Greenspan kept rates too low for too long in 2003–2004, setting up the housing bubble and Great Recession. He clearly helped the massive bubble in 1999–2000.
- Then Bernanke’s reluctance to raise rates above zero in 2012–2013, when the economy was manifestly recovering, refueled the asset price bubble.
- Yellen continued that course. Her reluctance to raise rates until Trump won the election, the economy was booming, and unemployment clearly falling was inexcusable.
This makes me think Powell is perfectly willing to walk away from that unofficial third mandate. Is he letting his inner Volcker show just a little bit? If so… damn, Skippy, it’s about time!If Powell doesn't come forward in the next couple of weeks and apologize for scaring the market, doesn't try to walk it back, we can be pretty sure he really intends for the Fed to not be an enabler of another asset bubble. Look, I'm a retiree living on my "life's savings": I want the markets to be healthy. It's in my financial best interest. But it's not in the country's best interest, or the world's, for the Fed to be involved in that. I don't want the Fed head to be the second most important person in the country (or the world).
The Federal Reserve should be just as concerned about Main Street as it is about Wall Street. The serial bubbles of the last 30 years all had serious negative consequences. Yes, the ride was often fun, and some of us made good money in both the up and down cycles. But Main Street would be better served with a steady-as-she-goes Fed policy.
Wall Street (and the financial world in general) should create earnings and value companies based on those earnings, and not game the system to the point where valuations get incredibly stretched and then the bubble pops. It kills the average investor who buys late in the cycle and then gets scared out of the market at exactly the wrong time. People come to see investing as a game Wall Street plays for its own benefit. In fact, it is anything but a game. To most people, investing is about retirement and life.
I disapprove of there even being a Federal Reserve Bank, with all the implications of a centrally controlled economy it brings, but for the moment the best we can do is hope to minimize the harm it does. They need to raise interest rates and crank back in the trillions of dollars worth of funny money they created during the Obamanation. Rates were so low for so long, and so much excess money was created that if another recession were to start soon, they'd be left with no tricks. They'd be in a shootout holding an empty magazine. Just a couple of short years ago, Janet Yellen was proposing (we hear) using negative interest rates to get people to spend and kick start the economy. That's the kind of
There's no real evidence that if rates go negative people will spend more to keep their savings from evaporating. In fact, there's evidence some savers, faced with seeing their savings not growing, double down on the saving, denying themselves even more and trying ever harder to save. As Jim Rickards put it: "As a result, many citizens are saving even more from retirement checks and paychecks to make up for the lack of a market interest rate. So a Fed manipulation designed to discourage savings actually increases savings, on a precautionary basis, to make up for lost interest. This is a behavioral response not taught in textbooks or included in models used by the Fed."I'm sure those of you who follow such news have seen the predictions of a recession in 2019 or 2020. The central banks need to have some ability to cut interest rates in order to do their "monetary stimulus" and that can only come by cranking back in (i.e. destroying) the money they created throughout 2008-2015. The problem is that the effect of that monetary creation was limited to the perverse effectiveness of helping only the people who got the money before interest rates and prices went up - as is typical of all Fed manipulations. The only way to make that go away is to End the Fed.
Monday, December 24, 2018
Merry Christmas to All
It's sort of annual tradition on my part to put up this post, or at least the essence of it, since I revise it pretty much every year.
Borepatch has an interesting article up on why we celebrate Christmas on December 25th. It might well be true. It sure has a lot of details that make sense.
Churches, like all groups, have personalities, and in the one I attend, it would be remarkable to toss a wadded up paper ball and not hit an engineer, nurse, doctor, or a tech professional.
Years ago. a friend sent me this contribution on the question of the exact date from a place dedicated to answering biblical questions.
Let me wish each and every one of you who stop by here a very Merry Christmas. Hold close the ones you love. Spend time with family or friends or both. Remember the good service members deployed far from home. If you're Military, LEO, or fire; EMT, Nurse or MD, and are one who must work while the rest of us celebrate, thank you.
(source)
Borepatch has an interesting article up on why we celebrate Christmas on December 25th. It might well be true. It sure has a lot of details that make sense.
Aurelian introduced his cult on December 25, 274 AD and it became really the first Empire-wide holiday. He succeeded in founding a common belief across the Empire, perhaps succeeded more than even he hoped. Because the idea stuck: Emperor Constantine didn't just introduce Christianity. It's from him that we get the word Sunday, since he decreed that across the Empire the weekly day of rest would be the day of rest - the dies Solis.I always say that in the church I go to, it's not news that most people say we have no real idea when Jesus was born and that the December 25th date comes from adapting to the Roman Saturnalia or other pagan holidays; nor would they be shocked if you told them Christmas has more secular than holy traditions associated with it and many things that are totally ingrained in the holiday traditions started out as advertising gimmicks. There was no little drummer boy when the events we portray as the nativity happened; in fact, the entire scene we call the nativity is a conglomeration of bits and pieces from multiple Gospels, and certainly did not happen within the first couple of days of Jesus' life. Nobody knows how many magi ("wise men") came to visit the child; we say three because of the three gifts listed, but it could have been almost any number. Furthermore, it wasn't at his birth; it was when Jesus was closer to two years old.
Churches, like all groups, have personalities, and in the one I attend, it would be remarkable to toss a wadded up paper ball and not hit an engineer, nurse, doctor, or a tech professional.
Years ago. a friend sent me this contribution on the question of the exact date from a place dedicated to answering biblical questions.
The truth is we simply don’t know the exact date of our Savior’s birth. In fact, we don’t even know for sure the year in which He was born. Scholars believe it was somewhere between 6 B.C. and 4 B.C. One thing is clear: if God felt it was important for us to know the exact date of the Savior’s birth, He certainly would have told us in His Word. The Gospel of Luke gives very specific details about the event, even down to what the baby was wearing – “swaddling clothes”—and where he slept—“in a manger” (Luke 2:12). These details are important because they speak of His nature and character, meek and lowly. But the exact date of His birth has no significance whatsoever, which may be why God chose not to mention it.I've heard another explanation for why December 25th was chosen. It's close to the solstice, the longest night of the year - which made it the darkest night of the year in those days. Jesus was the light of the world, and the symbolism of bringing light when things are at their darkest fits perfectly with the story. If someone came out with a convincing line of evidence that Jesus really was born on December 25th, I'd be surprised... but not terribly shocked. Again, paraphrasing that previous quote, not that it matters.
Let me wish each and every one of you who stop by here a very Merry Christmas. Hold close the ones you love. Spend time with family or friends or both. Remember the good service members deployed far from home. If you're Military, LEO, or fire; EMT, Nurse or MD, and are one who must work while the rest of us celebrate, thank you.
(source)
Sunday, December 23, 2018
Saturday, December 22, 2018
50 Years Ago Tonight
50 years ago tonight, Apollo 8 was on the way to the moon; the first three men in the history of history that will go around the moon, orbiting it for a day. The six-day mission full of firsts lifted off on Dec. 21, 1968, with its crew of Frank Borman, Jim Lovell and Bill Anders. It would feature the first time that humans had looked down on the moon from orbit; the first time that humans had seen the farside of the moon. And it would mark the first time men had ever seen the Earth rise over another world.
Apollo 8 was originally not conceived as the mission it became; it was intended to be part of qualifying the Apollo spacecraft in Low Earth Orbit (LEO). There had been only one prior manned Apollo mission, Apollo 7, and that had been only two months before in October. While a Saturn V had been test launched, it had never carried astronauts into orbit.
Apollo 8 was originally not conceived as the mission it became; it was intended to be part of qualifying the Apollo spacecraft in Low Earth Orbit (LEO). There had been only one prior manned Apollo mission, Apollo 7, and that had been only two months before in October. While a Saturn V had been test launched, it had never carried astronauts into orbit.
"NASA officials realized that this was risky, since Apollo 7 had not yet qualified the spacecraft when their tentative decision was made," a NASA historical document reported. The decision was further complicated by Apollo 8's need for a more powerful rocket, called the Saturn V, which had never been tested on a crewed launch. But after months of discussion, NASA decided to move forward with an Apollo 8 moon mission on Nov. 10, about a month before the launch.Space fans from those days will remember that critical rocket burns happened while the Apollo capsule was out of radio contact - over the far side of the moon. The burn to stop Apollo 8 from looping around the moon and returning to Earth had to take place while over the far side. A day later, the burn to get them out of lunar orbit and returning to Earth took place over the far side as well.
All that remained was the return trip home. Mission controllers waited anxiously Christmas morning as the crew turned their engine on again, on the far side of the moon.A cursory look through the blog history looks like I've written about Apollo 8 every year, but only on Christmas Eve. Christmas Eve was the day they orbited the moon, the day that the crew spoke to us of the "stark and unappetizing" look of the lunar surface and read from the book of Genesis, the first book in the Christian bible. Here on Earth, 1968 had been a tumultuous year. There had been riots in many places, assassinations and troubles all around the globe. On Christmas eve, in awe of what these men were doing, it seemed like the world held its breath and watched.
As they re-emerged, Lovell called out, "Please be informed, there is a Santa Claus," signaling that the ship was headed back to Earth. The crew landed successfully on Dec. 27.
Friday, December 21, 2018
About That Lurking C-Word
Tuesday is Christmas! Four days from now! Are you ready? There's still time!!
Seriously, I was sick of "Black Friday" ads a week before Thanksgiving. It would help the day feel "fresher" if they didn't start having Black Friday sales in the middle of Freaking July. And seriously: when did black Friday become a national holiday? When did it stop being the semi-official start of the Serious Christmas Shopping Season and become a Competitive Shopping Event? On the other hand, I got an email ad today (from Wilson Combat) that could legitimately be called an "after Christmas" sale notice. I'm sure that means something, I'm just not sure what.
The thing is, I love Christmas. I mean, most people decorate for Christmas way more than I do, and I've known people who plan their Christmas six months in advance, way before I do. I know a guy whose house decorations for Christmas put the local shopping centers to shame, and focused his whole year around Christmas. Maybe if you saw me, or saw our barely decorated little house, you wouldn't think so, but I love Christmas.
Last year, we broke with longstanding tradition of getting only a real tree and putting it up a week to 10 days before Christmas. We got a plastic tree, put it up early and stored it in the workshop after New Years. Not in the attic, in my workshop. It came out this year on December 1st and has been lighting us up every evening since.
Christmas is unique among holidays in America. It has a very strong Christian tradition (well, duh!) as well as very strong secular traditions, and I love them both. I love giving gifts to loved ones and friends. I love the old favorite songs and the whole feeling of this time. Yesterday, I had a dentist appointment and everyone in the office was wearing silly Christmas clothes. It added a smile and light heartedness that doesn't automatically go with dentist visits. The gift-giving secular tradition is so big that people in retail will tell you that Christmas often determines whether or not they stay in business. Getting back to the Christian traditions, another aspect of the holiday is the annual struggle to "keep Christ in Christmas" and not overlook the spiritual side of the holiday. One of my favorite facts in life is that there's actually a court ruling that tells you how many reindeer (three) a holiday display must have to remain "sufficiently secular" to be legal to display on public property. If I have three or more reindeer on display, it's secular, but if it's only two reindeer, I'm obviously trying to convert you! Even two and half, say I display two reindeer and a package of reindeer sausage, won't make it secular enough. You've just got to know that when lawyers are deciding that "three is the number and the number shall be three", someone had to suggest two and a half.
As we go into the Christmas weekend and the Big Day, take time to enjoy it and your loved ones. If you feel a need to get some perfunctory gift for someone you'd really rather not give to, I say don't do it. That's some sort of bizarre social ritual, not Christmas. Don't put yourself in debt for Christmas; even if it means the kids get a "meager" holiday. It won't hurt them and may just help them. If you're one of the 45% who recently said they'd just as soon skip the whole thing - I say skip it. It's still a federal holiday, so you have that going for you. Lastly, if you work in retail, the USPS, or package delivery service and will be running your buns off for the next four solid days, you have my sympathy.
Seriously, I was sick of "Black Friday" ads a week before Thanksgiving. It would help the day feel "fresher" if they didn't start having Black Friday sales in the middle of Freaking July. And seriously: when did black Friday become a national holiday? When did it stop being the semi-official start of the Serious Christmas Shopping Season and become a Competitive Shopping Event? On the other hand, I got an email ad today (from Wilson Combat) that could legitimately be called an "after Christmas" sale notice. I'm sure that means something, I'm just not sure what.
The thing is, I love Christmas. I mean, most people decorate for Christmas way more than I do, and I've known people who plan their Christmas six months in advance, way before I do. I know a guy whose house decorations for Christmas put the local shopping centers to shame, and focused his whole year around Christmas. Maybe if you saw me, or saw our barely decorated little house, you wouldn't think so, but I love Christmas.
Last year, we broke with longstanding tradition of getting only a real tree and putting it up a week to 10 days before Christmas. We got a plastic tree, put it up early and stored it in the workshop after New Years. Not in the attic, in my workshop. It came out this year on December 1st and has been lighting us up every evening since.
Christmas is unique among holidays in America. It has a very strong Christian tradition (well, duh!) as well as very strong secular traditions, and I love them both. I love giving gifts to loved ones and friends. I love the old favorite songs and the whole feeling of this time. Yesterday, I had a dentist appointment and everyone in the office was wearing silly Christmas clothes. It added a smile and light heartedness that doesn't automatically go with dentist visits. The gift-giving secular tradition is so big that people in retail will tell you that Christmas often determines whether or not they stay in business. Getting back to the Christian traditions, another aspect of the holiday is the annual struggle to "keep Christ in Christmas" and not overlook the spiritual side of the holiday. One of my favorite facts in life is that there's actually a court ruling that tells you how many reindeer (three) a holiday display must have to remain "sufficiently secular" to be legal to display on public property. If I have three or more reindeer on display, it's secular, but if it's only two reindeer, I'm obviously trying to convert you! Even two and half, say I display two reindeer and a package of reindeer sausage, won't make it secular enough. You've just got to know that when lawyers are deciding that "three is the number and the number shall be three", someone had to suggest two and a half.
A 2006 Zogby poll showed that 95 percent of folks are NOT offended when they hear the words “Merry Christmas.” The real kicker is that 1 in 3 are actually very offended when the words “Happy Holidays” push out the phrase “Merry Christmas.” This should not come as a big surprise because another poll by Fox News/Opinion Dynamics showed that 95 percent of Americans celebrate Christmas.Every year you hear about some overzealous morons somewhere deciding that the most innocuous secular symbols are too Christian. I hate to break it to them, but candy canes are nowhere to be found in Christian scriptures; nor are wreaths, trees, or decorative lights on those trees. They are not religious symbols. And even if they were, the absence of religious symbols isn't a diversity of views; it's presenting only the atheistic view. This year, the ubiquitous charge of racism joined the party as we learned that the 1960s stop-motion animated "Rudolph the Red Nosed Reindeer" is a horrible show charged with bullying, racism and homophobia. Of course, we also were also bludgeoned that "Baby It's Cold Outside" is about rape and not mutual flirtation, as was the intent, joining "White Christmas" in being banned. White Christmas was first singled out in 2014. Colleges are at the heart of this fake diversity fest.
As we go into the Christmas weekend and the Big Day, take time to enjoy it and your loved ones. If you feel a need to get some perfunctory gift for someone you'd really rather not give to, I say don't do it. That's some sort of bizarre social ritual, not Christmas. Don't put yourself in debt for Christmas; even if it means the kids get a "meager" holiday. It won't hurt them and may just help them. If you're one of the 45% who recently said they'd just as soon skip the whole thing - I say skip it. It's still a federal holiday, so you have that going for you. Lastly, if you work in retail, the USPS, or package delivery service and will be running your buns off for the next four solid days, you have my sympathy.
Thursday, December 20, 2018
Did Trump Just Manage to Toss His 2020 Chances?
I've said a bazillion times that I don't like following day to day politics. I'm sure as hell not following who's going to run on the Evil Party side, or if Trump is going to be challenged by his (alleged) party. I can't help but notice, though, that this week Trump has managed to alienate supporters all across the political spectrum.
Last week, he said he'd be willing to shut down the government to get funding for the border wall, then said a few days later that he wouldn't shut down the government if the Dems promised to fund the wall when the "emergency" funding resolution ends in February. After that, he effectively hopped back to step one when the blow back over that started. Of course, everyone knows of the public feud between Ann Coulter and the President, after her column, "GUTLESS PRESIDENT IN WALL-LESS COUNTRY". Which led the Prez to "unfollow" Ann. Unfollow! The horrors!
I've heard at least a half dozen callers to the talk shows saying that not funding the wall is Trump's equivalent of H.W. Bush's "Read my lips. No new taxes", which probably killed H.W.'s re-election chances.
Yesterday, Trump declared victory in Syria and said (in 25 words or less) "let the other countries pay for it", drawing praise from Syria, Russia, and Iran. While being in Syria isn't popular across all demographics, announcing the pullout has drawn resistance from military and his Republican allies.
It seems to have led to the resignation of General James Mattis, who thinks it's ill-advised. General Mattis, of course, is well known as Mad Dog Mattis and is probably the most popular and most highly-regarded member of Trump's team. He's also very likely the one man most responsible for the successful campaign against ISIS.
Tonight, rumors are swirling that we will be drawing down troop numbers from Afghanistan, too.
Finally, there's the bump stock ban. As I understand it, the Justice Department hasn't formally published the rule, but when they do so it starts the 90 day countdown until it takes effect and all bumps stocks must be either destroyed or turned in with no reimbursement, or their owners become instant felons. The coming lawsuits will probably delay the date it goes into effect.
Like virtually all gunnies I've seen or hear comment on this, I don't particularly care about bump stocks. Never had one, never cared about them, certainly never wanted one. The problem is that "machine gun" is precisely defined in ATF law and this ruling contradicts that. It sets the precedent that the next extremely anti-gun president could outlaw lots of other things by stretching laws however they see fit. From the standpoint of 2A advocates, it strongly reinforces that Trump is not our friend.
It's hard to imagine how much worse a week Trump could have had. Can he recover? Sure. The primary campaigns start next fall (I hear the Demmies start their debates in June). But he sure has pissed off a lot of different groups of supporters with these five things
Photo by Alex Wong/Getty Images
Last week, he said he'd be willing to shut down the government to get funding for the border wall, then said a few days later that he wouldn't shut down the government if the Dems promised to fund the wall when the "emergency" funding resolution ends in February. After that, he effectively hopped back to step one when the blow back over that started. Of course, everyone knows of the public feud between Ann Coulter and the President, after her column, "GUTLESS PRESIDENT IN WALL-LESS COUNTRY". Which led the Prez to "unfollow" Ann. Unfollow! The horrors!
I've heard at least a half dozen callers to the talk shows saying that not funding the wall is Trump's equivalent of H.W. Bush's "Read my lips. No new taxes", which probably killed H.W.'s re-election chances.
Yesterday, Trump declared victory in Syria and said (in 25 words or less) "let the other countries pay for it", drawing praise from Syria, Russia, and Iran. While being in Syria isn't popular across all demographics, announcing the pullout has drawn resistance from military and his Republican allies.
It seems to have led to the resignation of General James Mattis, who thinks it's ill-advised. General Mattis, of course, is well known as Mad Dog Mattis and is probably the most popular and most highly-regarded member of Trump's team. He's also very likely the one man most responsible for the successful campaign against ISIS.
Mattis released his resignation letter shortly after Trump’s announcement on Twitter, arguing his views on foreign policy were different than the president.
“Because you have the right to have a Secretary of Defense whose views are better aligned with yours on these and other subjects, I believe it is right for me to step down from my position,” Mattis wrote.
The general also expressed his support for sustaining the Defeat ISIS coalition overseas in his letter as well as the principles of opposing authoritarian regimes in China and Russia, and the importance of treating allies with respect.
Tonight, rumors are swirling that we will be drawing down troop numbers from Afghanistan, too.
Finally, there's the bump stock ban. As I understand it, the Justice Department hasn't formally published the rule, but when they do so it starts the 90 day countdown until it takes effect and all bumps stocks must be either destroyed or turned in with no reimbursement, or their owners become instant felons. The coming lawsuits will probably delay the date it goes into effect.
Like virtually all gunnies I've seen or hear comment on this, I don't particularly care about bump stocks. Never had one, never cared about them, certainly never wanted one. The problem is that "machine gun" is precisely defined in ATF law and this ruling contradicts that. It sets the precedent that the next extremely anti-gun president could outlaw lots of other things by stretching laws however they see fit. From the standpoint of 2A advocates, it strongly reinforces that Trump is not our friend.
Legally, however, the precedent set by Trump's bump stock ban is troubling, regardless of how you feel about the Second Amendment or define its scope. The president does not have the authority to rewrite laws that interfere with his agenda, whether the subject is guns or immigration. Principled critics of this administration should call Trump out whenever he oversteps his legal powers, even when they happen to like the outcome.Finally, I suppose for style points, Trump pushed and then signed a nearly $900 Billion dollar farm bill. It combines the usual mentality of the farm bills: help the major corporations, screw the small farm owners, hand out Food Stamps (SNAP) with no work requirements - only this time it adds lots of accommodations for hemp farmers.
It's hard to imagine how much worse a week Trump could have had. Can he recover? Sure. The primary campaigns start next fall (I hear the Demmies start their debates in June). But he sure has pissed off a lot of different groups of supporters with these five things
Photo by Alex Wong/Getty Images
Wednesday, December 19, 2018
Threading Breakthrough - Almost Done
Since I completed the flame eater engine, my main project in the shop has been resurrecting my CNC lathe and converting it to thread under CNC instead of doing that with the various drive gear options on my manual Sherline or big LMS3540 lathe. Today, I think I hit the 90% done mark - or better.
One of the reasons is that the drive gears on the LMS lathe (a SIEG SC4) are potentially hazardous to get working for fine pitches, since the only way I could get the gears to work had them sticking out of the lathe cover, where they could grab a sleeve or do something worse. I put up a video explaining the problem and then another showing the way I got it to work. My field expedient fix was to cover the exposed gears with a cardboard box.
The Sherline has its own inconveniences, although it doesn't expose you to gears with a motor running because it's hand cranked to thread.
My post last Friday showed that the results of a test which should just give some scratches on the blank I used and they appeared off. They were supposed to be perfectly overlapped but were spread out. By coincidence, a thread appeared on CNC threading on one of the forums I follow and that guy helped improve his results by increasing his motor RPMs and feed rate. I tried that and in that test, the five overlapping passes came out perfectly spaced and lying on top of each other. It took me a while to realize the scratches weren't as deep as they should have been, but after a couple of days, I found the combination and by this afternoon had successfully cut about 10 turns (half an inch) of 1/4-20 threads.
The commercial 1/4-20 nut threaded right on to it. Success.
The nature of computer work is that once you can walk one path you can walk many others, so I decided to get closer to the kinds of parts I did on my flame eater project and made a 10-32 screw in aluminum. I cut the blank to the outer diameter manually, not under CNC, and then rewrote the threading routine for the different sizes. Just before hitting the "run cycle" button, I decided to video it. This is 2 minutes of the system running (with me dabbing away chips and adding cutting oil). First try was a success.
Under 10 or 20 power magnification the threads look pretty rough and that's the only thing keeping me from saying it's done and adding more features. A commercial 10-32 nut still threads on properly and feels pretty good.
Ultimately, I'd like to be able to take pieces that have to have special threads put on them and do those pieces on this lathe. In the engine, there was a piece that was to be threaded 6-32, but only was big enough to have 3 turns exposed for the nut. It's on the left in this picture.
The part has operations done to it besides turning the OD of the bottom piece, and the major diameter of the small threaded stud, but it would be conveniently cool to put a piece of, say, 1/2" aluminum rod in the lathe, use the CNC to turn it to 3/8 OD over all, then turn the little stud (top) down the major diameter of a #6 screw, and finally cut the three turns of thread. All without taking the piece out of the lathe.
Gimme another couple of months.
One of the reasons is that the drive gears on the LMS lathe (a SIEG SC4) are potentially hazardous to get working for fine pitches, since the only way I could get the gears to work had them sticking out of the lathe cover, where they could grab a sleeve or do something worse. I put up a video explaining the problem and then another showing the way I got it to work. My field expedient fix was to cover the exposed gears with a cardboard box.
The Sherline has its own inconveniences, although it doesn't expose you to gears with a motor running because it's hand cranked to thread.
My post last Friday showed that the results of a test which should just give some scratches on the blank I used and they appeared off. They were supposed to be perfectly overlapped but were spread out. By coincidence, a thread appeared on CNC threading on one of the forums I follow and that guy helped improve his results by increasing his motor RPMs and feed rate. I tried that and in that test, the five overlapping passes came out perfectly spaced and lying on top of each other. It took me a while to realize the scratches weren't as deep as they should have been, but after a couple of days, I found the combination and by this afternoon had successfully cut about 10 turns (half an inch) of 1/4-20 threads.
The commercial 1/4-20 nut threaded right on to it. Success.
The nature of computer work is that once you can walk one path you can walk many others, so I decided to get closer to the kinds of parts I did on my flame eater project and made a 10-32 screw in aluminum. I cut the blank to the outer diameter manually, not under CNC, and then rewrote the threading routine for the different sizes. Just before hitting the "run cycle" button, I decided to video it. This is 2 minutes of the system running (with me dabbing away chips and adding cutting oil). First try was a success.
Under 10 or 20 power magnification the threads look pretty rough and that's the only thing keeping me from saying it's done and adding more features. A commercial 10-32 nut still threads on properly and feels pretty good.
Ultimately, I'd like to be able to take pieces that have to have special threads put on them and do those pieces on this lathe. In the engine, there was a piece that was to be threaded 6-32, but only was big enough to have 3 turns exposed for the nut. It's on the left in this picture.
The part has operations done to it besides turning the OD of the bottom piece, and the major diameter of the small threaded stud, but it would be conveniently cool to put a piece of, say, 1/2" aluminum rod in the lathe, use the CNC to turn it to 3/8 OD over all, then turn the little stud (top) down the major diameter of a #6 screw, and finally cut the three turns of thread. All without taking the piece out of the lathe.
Gimme another couple of months.
Tuesday, December 18, 2018
After A Year Without Net Neutrality
One year after the end of the FCC Chairman Ajit Pai ended the Obama-era Commission's (illegal, IMO) power grab of implementing "net neutrality" after being ordered by congress not to do so, we were supposed to have seen the end of internet. We were supposed to be sitting in dirt-floored hovels reminiscing about how there used to be this marvelous thing called "the Internet" where we could get the answer to any question we ever had, buy any exotic oddity we might ever want, and watch all the pirated movies cat videos we could ever want. Internet use was going to collapse to zero because the Evil Corporations were going charge by the Megabyte, and data plans were going to be priced where only tech titans and billionaires could afford them.
In reality: not so much. The typical internet speeds have actually gone up in the last year, according to an article in Wired, highlighted in the Washington Examiner.
The outrage expressed last year over net neutrality being revoked is almost comical - as are most of the "outrage of the week" stories, when we can look in hindsight.
For their part, Wired has basically changed from saying, "the sky will fall!" before the Net Neutrality rules were revoked to saying "the sky hasn't fallen yet" implying they expect it to fall once the Evil Internet Providers figure out how to screw everyone without losing too many customers. What they neglect in this analysis is that the largest providers were behind the Net Neutrality laws - they probably wrote most of it, in a true cronyism deal like most of the Obama years. If the laws are going to keep those Evil Providers from making big profits, why would they be behind it? Could it be to block competitors from getting started?
Another reality they don't talk about is that with the exception of the original ARPANET predecessor to the internet, which was largely paid for by the DARPA, (the Defense Advanced Research Projects Agency), the vast majority of the internet was built out by those same providers. Providers are trying to keep up with exploding demand for their product. There's an insatiable thirst for more bandwidth, but providers have to make a profit on what they're doing to invest in the future. Their problem is that some services overwhelm all the others.
Borepatch, who I consider a rather well-informed guy, said that fully 50% of traffic on the 'net is from two services: Google (mostly YouTube) and Netflix. If Net Neutrality's "all bits are equal" is law, that means that when the service is busy, providers will have to throttle Netflix and YouTube to allow email to get through, and other low criticality services like writing blogs or swapping recipes.
See, back to cat videos after all that.
Average download speeds across the US, from OOKLA, via PC.
In reality: not so much. The typical internet speeds have actually gone up in the last year, according to an article in Wired, highlighted in the Washington Examiner.
The Internet is actually faster in the United States. A new report by Ookla, a sister company to PC Magazine, shows that download speeds have increased 35.8 percent across the country.For the technophiles, note this is for fixed downloads. Mobile devices tend to be slower. The fastest Internet was reported in in Kansas City, Mo., where Google Fiber is concentrated.
The outrage expressed last year over net neutrality being revoked is almost comical - as are most of the "outrage of the week" stories, when we can look in hindsight.
Sen. Bernie Sanders, I-Vt., warned that losing net neutrality would threaten representative government.
This is an egregious attack on our democracy. The end of #NetNeutrality protections means that the internet will be for sale to the highest bidder. When our democratic institutions are already in peril, we must do everything we can to stop this decision from taking effect. https://t.co/8GGrJFMdrU— Bernie Sanders (@SenSanders) December 14, 2017
GLAAD feared gays and lesbians would be targeted.
— GLAAD (@glaad) December 14, 2017
Planned Parenthood weighed in for whatever reason.
The @FCC just voted to repeal #NetNeutrality rules — that required internet providers to treat all web traffic equally. This could make it more costly to access content or even block websites or information entirely.— Planned Parenthood Action (@PPact) December 14, 2017
For their part, Wired has basically changed from saying, "the sky will fall!" before the Net Neutrality rules were revoked to saying "the sky hasn't fallen yet" implying they expect it to fall once the Evil Internet Providers figure out how to screw everyone without losing too many customers. What they neglect in this analysis is that the largest providers were behind the Net Neutrality laws - they probably wrote most of it, in a true cronyism deal like most of the Obama years. If the laws are going to keep those Evil Providers from making big profits, why would they be behind it? Could it be to block competitors from getting started?
Another reality they don't talk about is that with the exception of the original ARPANET predecessor to the internet, which was largely paid for by the DARPA, (the Defense Advanced Research Projects Agency), the vast majority of the internet was built out by those same providers. Providers are trying to keep up with exploding demand for their product. There's an insatiable thirst for more bandwidth, but providers have to make a profit on what they're doing to invest in the future. Their problem is that some services overwhelm all the others.
Borepatch, who I consider a rather well-informed guy, said that fully 50% of traffic on the 'net is from two services: Google (mostly YouTube) and Netflix. If Net Neutrality's "all bits are equal" is law, that means that when the service is busy, providers will have to throttle Netflix and YouTube to allow email to get through, and other low criticality services like writing blogs or swapping recipes.
See, back to cat videos after all that.
Average download speeds across the US, from OOKLA, via PC.
Monday, December 17, 2018
A Looming Government Shutdown? It's Like Old Times
It happens so often it's boring. I can take a paragraph from something I wrote before, change a few "facts and figgers" and - boom! - it's up to date and fresh. Like this one from a mere 20 months ago:
As always, this is a bunch of melodramatic kabuki theater; made-up so that they can avoid doing their real job (creating and passing actual budgets) and instead pass their Continuing Resolutions, which (IMO) is done for that great DC buzzword Plausible Deniability. By making maximum melodrama, these pathetic dweebs get to think they're heroes who fix things just in time!
As a plus (to a politician) they get to make "good television", a medium suited for those with the worst cases of Attention Deficit, much like the photo opportunity with Trump, Pelosi and Schumer which was replayed almost on continuous loop on cable over last weekend. Depending on which pundit you like to listen to, Trump is going to shut down the government to win approval of those awful, racist, deplorables who voted for him, and will not be damaged by shutting down the government at all, or any attempt to shut down the wise and wonderfully beneficent government will be met with the Wrath of the Voters who dump anyone in favor of shutting it down.
In reality, a government shutdown is just about meaningless. There's a handful of workers that will stay home, the "non-essential" workers, and others who will show up and work without pay. They'll all get that lost pay once the shutdown is over. A year ago, in the "Schumer shutdown", government workers got an extra 3-day weekend. I don't think I've ever met someone who didn't like a long weekend, so the scary shutdown meant nothing to anyone.
You may be hearing background stories everywhere predicting a recession in 2019. I suspect some (most?) of these predictions are because it's the best thing that could happen to Democrats in their quest for power. With a booming economy, any president is hard to beat along with any incumbents from their party. Professional financial advisors are more upbeat than the typical press stories. In context, the Fed kept rates at historic lows for most of 2008-2015. For most of that time the rates were negative in real terms - less than the inflation rate. They created trillions of dollars out of nothing to get more spending (which, in the Keynesian world view, is the same as real economic growth). Now they need to put the brakes on and raise interest rates, which they've been doing since 2015. In a boom time, even Keynes himself said that government spending should go down. Instead we get a nearly $900 Billion dollar farm bill and deficits going up.
(That flat line at zero from 2008 - 2016 is what I mean by historically low. The Fed's rate had never hit zero before and the only way they could have gone lower would be if savers weren't paid interest, but instead had to pay interest to save - chart from ZeroHedge).
Ah, gee. It's like old times, gang. We haven't had a pending fake shutdown in forever! Gosh, it must have been back when the Administration Party and "Party of No" wore different tags. So long ago... It was September of 2016. I can barely remember that. Do you recall where you were? Do you even remember how old you were? Someday, we'll all talk about the great government shutdown of 2017, too. At this rate, it'll be around a year from now.Really, just change two links and it's up to date. But I didn't. It's not like this is the last time we'll ever see one of these.
As always, this is a bunch of melodramatic kabuki theater; made-up so that they can avoid doing their real job (creating and passing actual budgets) and instead pass their Continuing Resolutions, which (IMO) is done for that great DC buzzword Plausible Deniability. By making maximum melodrama, these pathetic dweebs get to think they're heroes who fix things just in time!
As a plus (to a politician) they get to make "good television", a medium suited for those with the worst cases of Attention Deficit, much like the photo opportunity with Trump, Pelosi and Schumer which was replayed almost on continuous loop on cable over last weekend. Depending on which pundit you like to listen to, Trump is going to shut down the government to win approval of those awful, racist, deplorables who voted for him, and will not be damaged by shutting down the government at all, or any attempt to shut down the wise and wonderfully beneficent government will be met with the Wrath of the Voters who dump anyone in favor of shutting it down.
In reality, a government shutdown is just about meaningless. There's a handful of workers that will stay home, the "non-essential" workers, and others who will show up and work without pay. They'll all get that lost pay once the shutdown is over. A year ago, in the "Schumer shutdown", government workers got an extra 3-day weekend. I don't think I've ever met someone who didn't like a long weekend, so the scary shutdown meant nothing to anyone.
You may be hearing background stories everywhere predicting a recession in 2019. I suspect some (most?) of these predictions are because it's the best thing that could happen to Democrats in their quest for power. With a booming economy, any president is hard to beat along with any incumbents from their party. Professional financial advisors are more upbeat than the typical press stories. In context, the Fed kept rates at historic lows for most of 2008-2015. For most of that time the rates were negative in real terms - less than the inflation rate. They created trillions of dollars out of nothing to get more spending (which, in the Keynesian world view, is the same as real economic growth). Now they need to put the brakes on and raise interest rates, which they've been doing since 2015. In a boom time, even Keynes himself said that government spending should go down. Instead we get a nearly $900 Billion dollar farm bill and deficits going up.
(That flat line at zero from 2008 - 2016 is what I mean by historically low. The Fed's rate had never hit zero before and the only way they could have gone lower would be if savers weren't paid interest, but instead had to pay interest to save - chart from ZeroHedge).
Sunday, December 16, 2018
The Perfectly Legal Corruption No One Cares About
That's the title of a column by Derek Hunter on Townhall today. Excellent article but maybe 1/100th as long as it could be.
The media is in a tizzy over the lawfare framing of General Michael Flynn, attorney Michael Cohen, and everyone else being ruined by the Robert Mueller investigations.
General Flynn had been the head of the Defense Intelligence Agency, the DIA, so surely he must have known the stakes in talking with the FBI, even though they said it was just a chat so no need for a lawyer. Surely that must be what they call a perjury trap: if you remember one detail wrong, one detail that doesn't match the transcripts (again, transcripts that Flynn must have known they'd have) or remember one thing differently than someone else has testified, you're guilty of perjury. Even if you're right and the first guy was lying.
(Nominated to chair - not sure it's a done deal yet, but "elections have consequences" you know)
Edit to add 2034 EST: This is post #3000 in the life of this blog. I'm not quite sure what to say, other than "day-um".
The media is in a tizzy over the lawfare framing of General Michael Flynn, attorney Michael Cohen, and everyone else being ruined by the Robert Mueller investigations.
General Flynn had been the head of the Defense Intelligence Agency, the DIA, so surely he must have known the stakes in talking with the FBI, even though they said it was just a chat so no need for a lawyer. Surely that must be what they call a perjury trap: if you remember one detail wrong, one detail that doesn't match the transcripts (again, transcripts that Flynn must have known they'd have) or remember one thing differently than someone else has testified, you're guilty of perjury. Even if you're right and the first guy was lying.
What do you think is more likely? That Michael Flynn couldn’t perfectly recall the contents of a phone call made while on vacation, or that Flynn decided that he’d lie to the FBI’s face without any legal counsel over the contents of a phone call where nothing illegal is discussed?Like Derek Hunter, it's hard to care much less than I do about Trump paying off a couple of whores to keep silent about having sex with him 12 years ago. He wasn't president at the time, he wasn't even running for office. He was "just" another New York City billionaire - a private businessman.
What I don’t like is when people whose salaries we’re all paying use more of our tax dollars to pay off people they’ve harassed and keep that quiet.The use of public tax money for the same thing, by elected congressmen and senators, is disgusting, reprehensible and vile. It should have never been allowed - just like allowing the same senators and representatives to engage in insider trading and other things "normal people" will get arrested for should never have happened.
There have been more than 260 settlements costing more than $17 million, paid for by you and me, so our elected Members for Congress can avoid being held responsible for things they’re now clutching their pearls over the President having done with his own money.
California Democrat Maxine Waters won her first term in Congress in 1990 with 79 percent of the vote. Her toughest reelection bid came in 2012 when she squeaked by with 71 percent. Yet every two years she raises a campaign war chest for that foregone conclusion.And that last paragraph is the problem. It's not limited to one party and it's not even a crime. These stories are only scratching the surface. As soon as one scam is clamped down on (remember the congressional check-kiting scandal of 1992?) they come up with another. They can always find a legal way to steal money.
With the millions of dollars she’s raised, Waters has paid her own daughter, Karen, more than $800,000 since 2004 to run a statewide mail campaign promoting other Democrats. This past election, where Waters took 75.8 percent of the vote, was a good year for Karen too. According to the Washington Free Beacon, “Karen is now owed $183,022.15 on top of the $108,000 she has already collected during the midterms.” Nice pay for essentially licking stamps.
Missouri Democrat William Lacy Clay Jr. was first elected in 2000 with a scant 75 percent of the vote. His closest reelection bid was in 2002 when he only managed 70 percent.
With his reelection a mere formality, he won this year with 80.1 percent, Clay still managed to slide a substantial chunk of his campaign cash to his sister. Michelle Clay is a lawyer who lives in Silver Spring, Maryland, a full 809 miles from Congressman Clay’s district. The Free Beacon reported, “From Jan. 4 until Oct. 31, 2018, Rep. Clay Jr. disbursed numerous payments ranging from $500 to $10,000 and totaling $198,500 to his sister's firm.”
...
[Last year, retiring] congressman Luis Gutierrez (D-IL), who paid his wife almost $400,000 between 2010 and then. That’s a nice nest egg to add to a Congressional pension, isn’t it?
These Members of Congress are not unique, and it’s not a scam limited to one party, and most disturbingly, it’s not even a crime. When you set the rules, the rules are always in your favor.
(Nominated to chair - not sure it's a done deal yet, but "elections have consequences" you know)
Edit to add 2034 EST: This is post #3000 in the life of this blog. I'm not quite sure what to say, other than "day-um".
Saturday, December 15, 2018
Bloomberg Business' Hit Piece on Supermicro Mother Boards
Last October, Bloomberg Businessweek ran an article alleging that Chinese contractors to American computer companies were implanting parts on the computer boards that spied on the users. I didn't run with the story because it honestly sounded improbable to me. The components were shown to be about the size of chip component but with at least one extra terminal. Shown here.
It's not the size that I thought was suspicious - that's a pretty common size these days - it was the idea that they could put a chip on there, with one extra pin (assume the other two are power and ground - those are pretty necessary - and yeah, there are some tricks to use pins for more than one thing) and use that to send data somewhere. Exactly how does this chip get put on the board if the printed wiring board wasn't designed for that part? There are no solder pads in the design, so the board has to be modified. Nobody would notice that? Exactly how does "China" get the data? Radio? With something that small and no obvious heat sinking, it's going to be low power, which means it's going to have to be transmitting to someplace close. Again, how? What frequency? What data rates? If signals are going around on the motherboard at "a few" gigahertz, you'd better be sending that rate if you're trying to capture what the users are doing. If it's not radio, the questions get even more uncomfortable. Serial link? Pretty much has to be in the same building. Use the computer itself to send the data? And nobody: no software, no traffic analysis, nothing notices?
It strained credulity, but the rumor-fest article quoted several people and gave them credibility. Trade magazine Electronic Design even proposed how it could be done, by attacking the baseboard management controller (BMC) which has complete control of the motherboard. One of the companies that Bloomberg singled out by name was San Jose-based Supermicro. From Bloomberg
Bloomberg's diagram showing how the attack worked.
It's not the size that I thought was suspicious - that's a pretty common size these days - it was the idea that they could put a chip on there, with one extra pin (assume the other two are power and ground - those are pretty necessary - and yeah, there are some tricks to use pins for more than one thing) and use that to send data somewhere. Exactly how does this chip get put on the board if the printed wiring board wasn't designed for that part? There are no solder pads in the design, so the board has to be modified. Nobody would notice that? Exactly how does "China" get the data? Radio? With something that small and no obvious heat sinking, it's going to be low power, which means it's going to have to be transmitting to someplace close. Again, how? What frequency? What data rates? If signals are going around on the motherboard at "a few" gigahertz, you'd better be sending that rate if you're trying to capture what the users are doing. If it's not radio, the questions get even more uncomfortable. Serial link? Pretty much has to be in the same building. Use the computer itself to send the data? And nobody: no software, no traffic analysis, nothing notices?
It strained credulity, but the rumor-fest article quoted several people and gave them credibility. Trade magazine Electronic Design even proposed how it could be done, by attacking the baseboard management controller (BMC) which has complete control of the motherboard. One of the companies that Bloomberg singled out by name was San Jose-based Supermicro. From Bloomberg
To help with due diligence, AWS [Amazon Web Services], which was overseeing the prospective acquisition, hired a third-party company to scrutinize Elemental’s security, according to one person familiar with the process. The first pass uncovered troubling issues, prompting AWS to take a closer look at Elemental’s main product: the expensive servers that customers installed in their networks to handle the video compression. These servers were assembled for Elemental by Super Micro Computer Inc., a San Jose-based company (commonly known as Supermicro) that’s also one of the world’s biggest suppliers of server motherboards, the fiberglass-mounted clusters of chips and capacitors that act as the neurons of data centers large and small. In late spring of 2015, Elemental’s staff boxed up several servers and sent them to Ontario, Canada, for the third-party security company to test, the person says.In that Bloomberg article, Supermicro, Amazon and others denied that any of this was true. This week, news was released that Supermicro had hired an independent company to audit their motherboards from China and that contractor had found no such things.
Nested on the servers’ motherboards, the testers found a tiny microchip, not much bigger than a grain of rice, that wasn’t part of the boards’ original design. Amazon reported the discovery to U.S. authorities, sending a shudder through the intelligence community. Elemental’s servers could be found in Department of Defense data centers, the CIA’s drone operations, and the onboard networks of Navy warships. And Elemental was just one of hundreds of Supermicro customers.
The company was unable to find any evidence supporting the Bloomberg report. The implants, according to Bloomberg, were camouflaged as tiny passive components and were added to the boards during manufacturing. The report said that the malicious chip was designed to give Chinese intelligence agents a secret door into the networks of almost 30 American companies, including government contractors.This is a tough question of "who do you believe?" The only people who are likely to know the truth are probably in Three Letter Agencies somewhere, forbidden to tell the story. Amazon and Apple denied the Bloomberg allegations about finding this malicious hardware. The thing is, it's kind of in the best interests of Amazon, Apple and Supermicro to cover up anything found. If customers don't have confidence in their products, sales collapse. On the other hand, it's kind of the in the best interest of Bloomberg Businessweek to spread stories like this. Increase sales of their publication. Perhaps affect the stock price of the companies they've named so owners or subscribers could get a good deal? It seems everyone has an incentive to tell less than "the truth, the whole truth, and nothing but the truth".
Charles Liang, Supermicro’s founder and chief executive officer, said Tuesday: “no government agency has ever informed us that it has found malicious hardware on our products; no customer has ever informed us that it found malicious hardware on our products; and we have never seen any evidence of malicious hardware.” He added: “Today’s announcement should lay to rest the unwarranted accusations.”
Bloomberg's diagram showing how the attack worked.
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