Saturday, March 6, 2021

A Ham Radio Series 22 - Operating on HF

I'm going to go somewhere I've never gone in ham radio coverage, and talk about something I've never talked about: actually operating your station.   And the reason I'm going to do that is because this weekend features one of a handful of operating events every year that might be fun to listen to and even operate.  Yes, I'm going to talk about contests. 

If ham radio has an aspect that's controversial, it's contesting.  People who are anti-contesting and want to get on the air and casually chat with friends or meet people they don't know get upset when a major contest happens and the bands are crowded.  While it's technically true that there are contests going every weekend and sometimes even on weekdays, most of the time you'd never know.  There's really only a handful that are close to taking over the bands.  I've never seen actual statistics, but it seems that the annual ARRL Field Day on the third weekend of June always gets a massive turnout; after that their November sweepstakes is big, and there are two major DX contests; the ARRL's and CQ Magazine's CQ Worldwide DX contest.  Other than Field Day, the other three contests have two weekends each, one for Morse Code (CW) and one for voice (SSB).  If you're counting, that's seven weekends out of the year when you're really likely to hear a contest.  For newbies, DX is said to come from D for Distance and X for unknown, but is generally taken to mean other countries, places or provinces that aren't in your regular operating areas. 

The crowding isn't that bad although it is an argument to have a station that is good on more than one band.  All of these contests use the "old" ham radio bands of 80, 40, 20, 15 and 10 meters, leaving 60, 30, 17 and 12 available.  During the contests, most of the bands aren't fully taken over, but there are other places to go. 

This weekend is the ARRL International DX Contest, SSB mode (only).  If nothing else, you can tune around the voice sections of the bands and listen to what it's like.  I'll borrow a screen capture from the excellent WA7BNM Contest Calendar (8-Day Calendar View) that displays what you need to know to play in this contest.


Let's start with the big one: why on earth should anyone care?  Assuming you have no desire to enter the contest and try to run up a score, I see two reasons.  First and foremost is to have fun.  DX contests bring stations from all over the world onto the air to compete to be the best in the different classes or (less formally) best in their country.  They also bring a ton of guys with smaller stations who are there to work more countries for their own interest or entertainment.  For people who don't strive to work other countries, there's a persistent image of straining to hear weak stations and the farther away they are the weaker.  While it does happen, I can't begin to tell you how many times I've heard people surprised at how loud and easy many of their DX contacts are.

A more pragmatic reason is that it's good training for operating in bad, crowded conditions.  Much like disaster communications, the messages are few and you have a pretty good idea what you're going to hear.  In this contest, you'll tell each other a signal report (you can get strange reactions if you say anything other than "five nine") and either your state or province (if you're in Canada) or the operating power if you're in another country. 
A contest exchange might be as simple as this:
CQ Contest CQ Contest, Pappa forty-two Alpha
Pappa 42 Alpha, Whiskey Seven Charlie Whiskey
Whiskey Seven Charlie Whiskey, you are Five Nine Kilowatt, QSL?
QSL, you are Five Nine Montana. QSL?
W7CW, QSL, 73, this is Pappa forty-two Alpha, QRZ?
Are these Q signal abbreviations familiar? Need a refresher (pdf warning)?  Simply: QSL? (as a question) means, "do you confirm reception?" and without the question mark means, "I confirm copying."  QRZ? means, "who is calling me?" and is used to ask if someone else was responding to his CQ (calling any/all stations). 

Let me throw in another reason to play in the contest.  The contest started Friday night at midnight UTC - that's 7:00 PM EST and 4:00 PM Pacific.  It will end at midnight UTC Sunday night.  That means the first 24 hours of the contest are gone already.  It also means for the stations that are working everyone they can hear, contacts are getting harder to come by.  That, in turn, means they'll listen harder for you and will be just as happy to give you a contact as to get one themselves. 

Contests are actually facing difficult times in keeping going.  Big contests like this bring a handful of really "big gun" stations, who have sunk astonishing amounts of money into their efforts.  They compete in the class called Multi-Multi, which means multiple stations on the air and multiple people operating.  The problem is that the financial investment is so huge that new stations are exceptionally hard to get started.  Many contests, like this one, have entry categories aimed at the little guy.  Single operator single band, single operator low power, single operator all band are examples.  I recall one contest (CQWW, I think) that has a category for people with small antenna systems, something "wire antenna and tribander" is the class. 

I bet nobody expected me to talk about this.  The least technical aspect of radio - operating. 



Friday, March 5, 2021

Another Strike Against Boeing and the SLS

According to a news item in the Ars Technica weekly "Rocket Report,"  George Abbey, NASA veteran as former director of Johnson Space Center and an influential, long-time human spaceflight leader, in a report for the Biden administration (pdf warning) has said that the Space Launch System (SLS) should be reconsidered.  The goal of the document, from the Baker Institute, was to provide decision-makers "relevant and effective ideas" for supporting the nation's policy goals.
Launch costs should matter ... "In view of the current availability of a significant number of commercial launch vehicles with proven payload capabilities, as well as the industry's progress in providing a launch vehicle with significantly greater lift capabilities, the Biden administration should reconsider the need for the SLS during its annual budget review," writes Abbey, who is now a senior fellow in space policy for Rice University.
I know that it may seem that I'm picking on the SLS, but it seems to be the embodiment of what I consider "old space."  The program was started for the political benefit of spreading money around rather than for a specific mission, and was changed over and over again as projected missions changed.  Now, approaching five years late, the dates on their schedule appear wildly optimistic. 

Last January, 2020, NASA and Boeing delivered the first (partially) completed SLS core stage to Stennis Space Center, where an unused half-century-old test stand was refurbished for several hundred million dollars for a single major objective: the Green Run. 

The Green Run amounts to a full-duration (eight minute) static fire of the SLS core stage: the main liquid-fueled booster and its four repurposed Space Shuttle Main Engines (SSMEs).  Prior to that ignition and burn test, Boeing and NASA would put the rocket through a number of other basic tests for the first time, including power-on, modal analysis, and a wet dress rehearsal (a static fire without the ignition).  If you watch SpaceX at Boca Chica, this is what you see going on when a new Starship prototype goes to the test stand.  They take a month, but it's a much smaller vehicle.

At the time of arrival of the SLS core at Stennis, ever zealously overconfident NASA and Boeing officials talked about the Green Run like it was a small, moderately inconvenient hurdle set in front of their flawless SLS rocket.  A Boeing official estimated that the rocket would complete the test campaign and be ready to ship to Kennedy Space Center by the middle of last year!

Of course, that didn't happen.  A full year of apparently unanticipated issues with the vehicle led to January's static fire test that ended with an aborted test 62 seconds into a planned eight minute firing, about 13% of the desired run.  After an embarrassingly long time before they announced they would actually insist on a re-test, NASA and Boeing discovered an engine valve issue for the second time (the first was last November), requiring at least another 4-6 weeks to repair. That valve was fixed on March 3rd, setting up a second static fire attempt no earlier than March 16th.


SLS-1 Core at Stennis Space Center.  NASA photo.

Here's the big issue.  This SLS core is intended to fly the first, unmanned, orbital Artemis mission.  Hilariously, NASA and Boeing are still sticking to their schedule fantasy and continue to parrot the party-line that SLS's Artemis-1 launch debut with this prototype is still on track to launch in "November 2021."  That date was set almost a year before the SLS Green Run schedule delays ballooned by at least nine months.  If NASA and Boeing are lucky and there are no more failures that eat months at a time, Artemis-1 might fly by the fall of 2022.



Thursday, March 4, 2021

And the SN10 Clean Up Begins

With no official words from SpaceX about exactly what appears to have failed that caused SN10 to RUD (Rapid Unscheduled Disassembly), we can turn to the unofficial sources we have.  In terms of what happened, I went to Scott Manley, who seems to have good track record.  In this video, he does some of the things I've seen him do before. He gets videos from several sources and watches them frame by frame.  Watch this.  It has some great shots in it.  I'll wait.   


I think a big important clue is the legs not deploying and locking into position.  The Starship lands hard and even noticeably bounces, as some of us said yesterday.  If all of the legs had been locked in position, it might have withstood that better, but with only three of the six locking in place I think they all would have collapsed.  In the still frames showing SN10 on the ground, it appears to be sitting with its base on the concrete pad, not on its legs. 

Another big, important clue is that fire on the side of 10 as she's getting ready to land.  That gets bigger, and continues even with the fire suppression system spraying water.  There's evidence of a methane leak, a plumbing problem, that started when the two unneeded engines were shut down.  SN10 lands trailing fire out the side.  Once it was on the ground, it seems possible some amount of fire continued, eventually leading to the final conflagration. 

That said, I agree with Scott that this is a validation of the entire landing sequence - from a belly flop to vertical, powered landing.  (I've seen some commenter somewhere refer to this maneuver as a Crazy Elon.  I'm assuming the phrase is meant to echo the Crazy Ivan maneuver.  That term started in submarines as response to a Russian captain, but now is widely used.)

Meanwhile, we know that SpaceX Boca Chica has started working on clearing debris.  Bluto the giant crane was moved to the landing pad area today, and there are reports that work has begun.  One thing that seems to be positive here is that the pieces are much bigger and fewer than the pieces SN9 left.  


Photo by Mary, @bocachicagal, of course. 

Due to having morning commitments that required a night's sleep, we didn't get up for the 3:24 AM launch of Starlink-17 but the "most delayed" Falcon 9 mission went off without a hitch, successfully placing another 60 Starlink satellites in orbit and recovering Falcon 9 booster B1049 for the eighth time.  We did watch the highlights in this SpaceX video this morning.  

For unknown reasons, it was announced in advance that the video from the booster would not be available, so that most of what I consider the interesting things to watch weren't there to watch.  There was a brief video image of the booster on the deck of the recovery drone, but the camera cut out as it was just about to land (the camera cutout happens most of the time).  We don't know if this is a new policy, if something was wrong in the hardware somewhere, or exactly what was going on.  I just hope they don't keep this policy.  

The next Starlink launch is set for Sunday night at a more friendly time for us: 10:41 PM EST.  I'm hoping the booster cameras are back for the mission.



Wednesday, March 3, 2021

SN10 Sticks the Landing ... and Then Explodes

A truly remarkable test flight from SpaceX today. 

It was a long day of waiting for the test flight. At around 3PM Eastern, they counted down to zero, and ignited the engines which were immediately shut down in an automatic abort. After some analysis of all the data from the rocket, they decided they'd reset everything and start over. Musk later explained that the three Raptors were producing too much thrust and they could fix that.

Number 10 ended up launching at 6:14PM EST, proceeding through the mission profile we've become familiar with - starting out on three engines, then sequentially shutting down two out of the three engines during ascent to hit the ~10km altitude (~6 miles) to keep from going supersonic.  After hovering at 10km for several seconds, they shut down the one remaining engine that was burning and began the guided belly flop down to about 1km. This is where the difference showed up as all three raptors successfully restarted; then one shutdown followed shortly by a second shutting down and the Starship successfully touching down with one engine burning.  When the dust and exhaust cleared, SN10 was standing there proudly.


This view was on a channel I don't ordinarily watch, but he had a link to the SpaceX livestream that I couldn't find elsewhere.  The Lab Padre Nerdle cam can't track the flight properly. 

Being just after 6PM and during dinner, I didn't just sit and watch SN10 standing there, I went back to dinner and watching a little news commentary on TV.  When I came back, she wasn't still standing there, just ominous smoke.  Backtracking to 5:21 CST on the tape showed the landing, and fast forwarding about 8 minutes revealed that SN10 suddenly blew up, going eventually out of the frame, around 300 feet above ground. 


Why?  If you watch the SpaceX video, which cuts off soon after the successful landing, you can see that the vehicle lands hard - a bounce is visible.  Look for more videos in the next couple of days.  In the videos I watched, a fire is visible at the base of the SN10 right after shutdown.  One of the explanations is that the fire spread.  In one view, the rocket looked slightly tilted.  I don't think there has been a landing on the stubby little landing legs these prototypes have that didn't result in some legs breaking and introducing some tilt.  In another view, SN10 appeared to have no more than a few inches to a foot of clearance between its aft skirt and the concrete pad.

Quite a while ago, Musk had said that they were going to upgrade the legs on Starship to something more reminiscent of the Falcon 9.  The tilt we've seen in SN5 and SN6 after their hops, and apparently on Starship SN9 as well is due to compressing the legs to the point that they break a crumple zone on the legs.  The Falcon 9 also has legs that collapse if they land too hard and it happens with some regularity, but whatever the solution, Starship's legs are comically short and don't offer any shock absorption.  There was talk a month or two ago of scrapping any prototypes between 10 and 15, and just going to SN15 because it has a much evolved design.  Apparently they actually did scrap out 12 to 14.  Today we heard about SN11 being moved to the pad for the next Starship test flight.  Maybe they should jump to SN15 now? 

All that said, assuming the problem was from a fire which, in turn, was from landing hard because of the known leg problems, it really can't diminish the fact that today was a turning point in Starship design.  It was day of extraordinary success for SpaceX. 



Tuesday, March 2, 2021

Space News: SN10 Test Flight Imminent and Big Rocket Lab Announcement

If you're waiting to see if the new method of lighting the three Raptors on SN10 will work better than the "we were too dumb" version on SN9, this is very likely your week.  In fact, tomorrow might be your day.  The weather was too bad yesterday and the first part of today to attempt, but the Temporary Flight Restrictions that will allow flight to 10 km are valid tomorrow through Friday.  At about 2:30 this afternoon, Boca Chica Village resident and NASA Spaceflight's regular photographer on scene, BocaChicaGal Mary, retweeted:
Happy to let y’all know that I have been asked to evacuate for Starship SN10 launch attempt tomorrow. It looks like it will be a beautiful day for a launch. I can’t wait to see SN10 nail the landing!


A screen capture from Nerdle Cam with SN10 on the left and SN9 right back in January. 

It looks like everything is in place to say they'll attempt the test tomorrow.  The other two test flights were both fairly late in the day, so that's the only clue I have.

Here within viewing distance of the Kennedy Space Center/Cape Canaveral Space Force Center complex, we had a third straight scrub of the next launch of 60 Starlink satellites, the mission called Starlink V1 L17 or simply Starlink-17.  So far this week, they had an abort called by the Falcon 9's software with 1:24 minutes left in the countdown for a Sunday night launch, a Monday evening launch and now tonight.  On Sunday, Teslarati was calling this, “by far – SpaceX’s most delayed Starlink launch since the company began launching the spacecraft in May 2019.”  



New Zealand/US company Rocket Lab announced a heavier lift, reusable booster called Neutron which they intend to fly by 2024.  The rocket will have a capacity to orbit of eight tons (I'm sure that will depend, as always, on exactly which orbit) intended for launching constellations of satellites like the Falcon 9 does.  It's intended to be rated for manned spaceflight, also like the Falcon 9.  The payloads a Falcon 9 can lift to orbit can exceed 10 metric tons, but can also be quite a bit lower, depending on the orbital height, launch facility and all those important details.

That announcement, however, is a routine corporate announcement.  What you really want to see is the Peter Beck (founder/CEO) video at their twitter account.





Monday, March 1, 2021

There Was a Hidden Message in Mars Perseverance's Parachute

Did you notice the odd coloring on the parachute that Perseverance used to land on Mars?  Perhaps in this video?  I noticed the parachute didn't look like a typical alternating red and white segment pattern but didn't think much about it. 


Because I don't have a Twitter account and don't live on the app full time, I didn't notice that apparently NASA officials said it contained a hidden message written in a code.  Allen Chen, the entry, descent, and landing lead for Perseverance, dared the public to figure the message out during a press conference last Monday.  Challenge the Internet nerds?
Internet sleuths cracked the message within hours. The red and white pattern spelled out “Dare Mighty Things” in concentric rings. The saying is the Perseverance team’s motto, and it is also emblazoned on the walls of Mission Control at NASA’s Jet Propulsion Laboratory (JPL), the mission team’s Southern California headquarters.

The parachute’s outer ring appears to translate to coordinates for JPL: 34°11’58” N 118°10’31” W.


There's a long history of leaving messages behind.  As Allen Chen said, “People can’t resist putting a little personal touch in their work,” Chen said. “But the vast majority of these will never be known — even by me.” 
The Curiosity rover, which landed on the Red Planet in 2012, had tiny holes dotted in its hollow aluminum wheels to allow Mars pebbles caught inside to escape.

Those holes read “JPL” in Morse code. So when Curiosity roved the surface, “JPL” was stamped in Morse code on the Martian soil (though it was erased shortly after by the Martian wind).
It's really not uncommon to find engineers leaving some sort of personalization in their work, like their initials, or some sort of logo.  I've seen them on things from printed circuit boards to inside integrated circuits and on spacecraft before flight.  

I'd explain the code, but I don't want to ruin it for you.



Sunday, February 28, 2021

The Changing of the Projects - Part 2 - Comments to the Comments

There were a bunch of really great comments to my post last night about the next engine and the other project I'm working on and the general topic.  Many of them resonated with things I've been thinking of, so much that I thought it would tough to get to them all but there are similarities.  Hope this isn't too "me, me, me, me" for everyone else. 

There were several comments along the line of building a small but useful engine, and several people referred to a Stirling engine.  A useful engine is something I've given a lot of thought to and is part of the reason I'm interested in building that hit and miss engine; it's 2-1/2 cubic inches.  I don't know how much power it's capable of, but as a guideline I think a good engine can get 1 HP per cubic inch.  I seriously doubt that I could get 2-1/2 HP out of it, but maybe it could be 1-1/2 or 1 HP.  Here's what I consider a really important number for you.  It's slightly off the exact value but easier to remember. 

One horsepower = 750 watts.

I can think of that engine as 750Watt to a 1,125Watt battery charger/power supply.  I could wrap a belt around the big flywheel hub visible in that picture and use the engine to drive a generator.  (It's more prudent to go with 80% of those numbers because you'll have inefficiencies in your charging system.) 

I know that Stirling engines can do useful work, but I don't know how big a Stirling engine to think about to get 750 watts.  They definitely have their place, I just don't know what it is.  I've seen guys use one to charge a cellphone which to me is touching the bottom end of the useful scale. 

WCR, if you have 3HP (2,250 watts) worth of steam, why not use a steam engine instead of a Stirling?  There are tons of very capable steam engine designs and every engine builder seems to build at least a couple.  Are you thinking of a Stirling engine because of some advantage they have?  (that I don't know about...)

Stefan, I think your approach is a cool idea.  500W out of a steam engine to run a generator and charge batteries, is a good, useful size; to a 12V storage battery, half a kW is over 36 amps.  

An idea I keep thinking about, but have no idea how to really get there, is the widely available 49cc engines like they use on motorbikes.  These "49ers" are almost exactly 3 cubic inches, and the parts are available everywhere.  You can buy an entire, ready to mount and run engine for well under $100.  If you go to eBay, you'll find all the parts you can imagine.  How about a carburetor for $11?  The RC model carb on my Webster cost over $30. I see pistons for 7 to $10, too.  I just don't know that those parts fit in "any" 49er engine and I can see buying a bunch of parts only to not have them fit together.

I don't know how much the piston in my Webster cost, but among the critical parts in an internal combustion engine is how well the piston fits.  The real cost of the piston is the hours of measuring, remeasuring, and generally agonizing over the fit.  A ready made cylinder and piston that fits it is really tempting.

And Titaniumboy - I'd never heard of the BAXEDM project. I know of the existence of EDM but not much about what it really can do and do for me. I'll be looking into that.


A PM Research #3 steam engine.  Fairly small, at 0.15 cubic inch displacement, but available as fully machined parts so all that's left is to assemble it.  Their #6 engine is 4.4 cubic inches, but is castings to machine and assemble yourself. 



Saturday, February 27, 2021

The Changing of the Projects

While I haven't decided that my Webster engine is just not going to get any more effort devoted to it, I haven't touched it in a week.  I just have had no luck in getting it to run better.  If anything it has gotten worse.  Maybe it's time to put it on a plaque and stick that on the shelf, but I keep hoping for ideas.  

I don't really have anything picked out to build for the next project.  I have several sets of prints I've downloaded over the years for potential next projects, but nothing has given me that "I have got to do this" feeling.  Naturally, I'd like something that runs better than this engine, and overcomes it's weak spots - I thought relying on the piston creating vacuum to open the intake valve wasn't as reliable as using a push rod to open a valve. 

There's a popular model that I've seen at all both of the shows we've been to that I'm considering.  PM Research sells a kit of castings for a 1/4 scale model of a Hit and Miss engine from the early 20th century that kind of appeals to me.  It had the advantage of being bigger than the Webster; it's just about 2-1/2 cubic inches vs. 3/4 cubic inch.  The flywheel seems just about the limit of what I can turn on my lathe at 8-1/4 diameter (I have an "8-1/2 by" lathe).  This is the water cooled version and they make one that doesn't have that big tank on the right.  The water cooled version was the first model I ever saw, so I think of water cooled as the way to make this engine.


The main drawback is that kit is $500 and I'm sure there will more expenses along the way.  I've never machined something from castings, so there would be lots of learning, that's for sure.

Other thoughts include a Stirling Engine of some sort, or perhaps not an engine at all.  Maybe an orrery

My main project lately has been resurrection of an old project, but on the electronics/ham radio end of the house.  Long time readers might remember me talking of trying to get my ham radio linear amplifier running after the lightning strike we had back in August of '19; summary here.  After I got the insurance reimbursement for the amplifier, I couldn't bring myself to throw it out.  Why?  For all the world, it seemed like the only thing wrong with it was the high voltage/high current power supply.  Unfortunately, the only way I could know that would be to replace the power supply. 

Somewhere along the line, I got the idea that I could buy a cheap, lower current power supply and test the radio frequency (RF) deck one subcircuit at a time.  I found one on eBay for $72.  If it ends up being a waste and I don't fix the amplifier, then I'll put it back on eBay myself.

The amplifier is roughly 1/3 power supply and 2/3 RF deck.  The RF deck is my home turf and I feel confident I could fix anything broken in it.  The amplifier has four identical amplifier modules based on a transistor I actually worked with about 20 years ago.  I did primarily receiver design for a living but would help optimize or solve problems with RF power amplifiers that someone else designed. 

The power supply is more a question of determining how much I need to keep and how much I can get rid of and to make that call I pretty much need to understand their schematics and other documentation.  Sparse, but far, far better than what I had in the fall of '19. 



Friday, February 26, 2021

SpaceX Swaps “Suspect” Raptor, Retests in Under 48 Hrs

At the end of Wednesday's column on the SpaceX prototype elevator, I mentioned that on Tuesday they had static fired SN10 but that it apparently did something wrong because one of the three Raptor engines was swapped out Wednesday.  In a tweet, Elon Musk had said one was “suspect” and needed to be swapped out.  


Bearing in mind that SpaceX is intending these engines to be manufactured and used in numbers unprecedented for any rocket engine and you can understand how they might have a ready inventory and then test all three again.  The engines that were fired yesterday should have zero degradation from running for a couple of seconds, so put in the new one and test all three. 

That's what they did yesterday.  The test subjectively looked and sounded better to me, just based on seeing bunches of these static firings


For some reason, I couldn't get this to start at other than time = 0.  If you set the bar to 2:10 you should be less than 10 seconds before ignition. 

If you've seen any of the chatter about Elon Musk and the crypto currency called Dogecoin, you might appreciate the joke on the new Raptor waiting to be installed.


"A Raptor Engine labeled “Under Doge” (serial number unknown) was delivered to the Starship build site in Boca Chica just now, and Raptor SN56 (green nozzle) took its place on the Raptor van, presumably headed back to Hawthorne or Mcgregor.
@NASASpaceflight"  from Twitter user Jack Beyer.

Given how SpaceX turned around SN10 from a questionable static firing to an apparently successful firing within 48 hours, it might catch your attention that the SLS second static firing test (Green Run Test 2) has slipped out to NET Mar 16. (NET = No Earlier Than)  The SLS was test fired in January and aborted at 67 seconds over a "finicky" valve.  The valve was repaired and during further testing, another valve in the same section failed.  Replacing an engine on Starship took less than a day.  Replacing a valve on SLS will take three weeks. 

In any comparison like that, Starship is going to look better than SLS.  Starship has been designed to be worked on easily at this phase in its development when SpaceX uses the "test to failure, fix, repeat" mantra.  SLS has not been designed for any of the rapid turnaround features that Starship has.  Even SpaceX’s Falcon 9 rockets, the world-standard for reusable orbital-class boosters, would have a hard time challenging that engine swap turnaround.  My guess is that it would take less than a week to swap engines in the Falcon 9, too.   I think we've seen it before. 



Thursday, February 25, 2021

Do You Like Bridges That Don't Fall Down? Cars That Don't Explode?

If you like all those aspects of modern life we've become used to; bridges that don't fall down, cars that just run, aircraft that don't fall out of the sky, things like that, you might want to get involved with your local school board.  The "math is racist" nonsense is really getting out of hand.  

Stephen Green at PJ Media has gotten a little deeper into the subject in his regular "Insanity Wrap" column on PJ Media web site.  It has gotten worse since I last looked at what the advocates were saying back early in the Obama years, about 2011.  I downloaded a file from Radical Math and their emphasis was that thinking about math was too foreign to some people and the teachers needed to make it relevant to their lives.  Now it's gone hard left and the arguments are that math is part of systemic racism and white supremacy.  


The 82 page pdf document contains month-by-month programs for the math teachers, September to June.  This is the summary of the teaching goals for April.  I want  you to really look at the bottom paragraph on the left and this sentence in particular:  “Schooling as we know it began during the industrial revolution, when precision and accuracy were highly valued.”  There's no need for precision and accuracy today?  To hand the floor to Green.
Today we build little four-banger car engines that produce more than 300 horsepower, reusable rockets, entire constellations of communications satellites operating in every imaginable orbit, and stealth jet fighters that lose their near-invisibility if a single element is slightly out of whack.

But no, this modern age of ours no longer values precision or accuracy.

Well, we’d better, if we want to prevent the whole damn system from falling down around us.
We could do days on the need for precision and accuracy.  How about landing Perseverance on Mars after seven months and hundreds of millions of miles of travel?  How about creating rocket engines and getting the analyzed performance out of them?  Digging underground tunnels and having them meet up properly?  The world offers tons of examples.  Do these "teachers" think that precision and accuracy only come from the computers? 

This "2 + 2 = 4 is racist" nonsense is a dire threat to the kids in school and to everyone in society by the time they're working for a living.  In particular, as Green put it:
Real racism is telling black and brown kids that wrong answers are OK, and thus condemning them to second-rate educations — if that.
They would do much better for their students if instead of that, they told them that "I'm bad at math" is just a myth



Wednesday, February 24, 2021

SpaceX Prototypes An Elevator... Whut?

You may recall that back in May of '20, NASA downselected to three companies to take us from the Lunar Gateway down to the lunar surface by creating the Human Landing System (HLS).  The biggest contract, $579 million went to the “National Team” led by Blue Origin; the next biggest at $253 million went to a team led by Dynetics, while the smallest contract, $135 million, went to SpaceX for a lunar landing version of the Starships we watch daily over in Boca Chica, Texas. 

Today, as an almost "oh, by the way", we learned that SpaceX has prototyped and tested a vital piece of the hardware that hasn't existed until the last week or so. They prototyped the elevator that will take the astronauts from the 60 meter tall Starship down to the lunar surface.  The elevator looks like this.


The story was tweeted by Eric Ralph, the SpaceX correspondent for Teslarati, and published details there as well.  He adds an interesting point from the standpoint of watching them much of the day.
On a separate note, it’s unclear when or where SpaceX built and tested the first Starship elevator. The photo NASA’s Mark Kirasich provider appears to show an elevator prototype situated inside a steel Starship ring with the sky visible, but nothing like that setup has been spotted at SpaceX’s Boca Chica Starship factory or former Cocoa Beach production facilities. That leaves its Hawthorne, California factory or, perhaps, a mysterious “Roberts Road” facility on Kennedy Space Center (KSC) land. Either way, it certainly appears that SpaceX has yet to show all its cards and is doing everything it can to convince NASA that Starship is worth additional HLS contracts.
The May '20 post I linked to at the start of this article says that this Human Landing System contract was for a short period, ten months, which means it ends in March.  March is next Monday.  NASA says they hope to further select, probably two of the three, in the next few weeks but maybe as far out as April.  But saying "next few weeks" includes the start of April.

While Blue Origin and Dynetics have delivered some neat mockups of their landing approach, SpaceX has more flying hardware than anyone.  In the ten months since their contract award, SpaceX has built no less than eight full-scale Starship prototypes, performed about two dozen wet dress rehearsals and static fires with those prototypes, and performed two powered, 150m hops and two high-altitude test flights.  Add this elevator prototype and it sure seems like the most hardware by far. 




While on the topic of SpaceX Starships, SN10 had a static firing yesterday but it apparently wasn't in full compliance with the goals as at least one of the three Raptor engines was installed today. They're approved for a road closure tomorrow, and flight TFRs cover the 25th to the 27th.  I expect they'll try to static fire again tomorrow to test the replacement engine, and it remains possible they could repeat the SN8 and 9 test flight before Monday.



Tuesday, February 23, 2021

Democrats Fight to Bring $15 Min Wage Back From the Dead

Earlier in the month, as talk about a $15/hr federal min wage was circulating, Biden surprised lots of us by signaling to governors that the wage hike likely isn’t happening.  Since that time, the die hard $15/hr advocates have been scheming ways of getting it passed even if Biden doesn't want it (or doesn't admit he wants it).  The latest gambit appears to be playing games with parliamentary rules in the Senate, as explored by Politico.
The budget tool that Democrats are using to steer Biden’s plan through Congress without GOP support, known as reconciliation, is laden with thorny restrictions waiting to ensnare the $15 minimum wage boost they've added to the next tranche of coronavirus relief. The wage increase is also running into strong headwinds from two influential Senate Democratic centrists, Joe Manchin (D-W.Va.) and Kyrsten Sinema (D-Ariz.), who are both resistant to enacting the sweeping policy change through the powerful budget process.
Did you get that?  The way they're going to try to push the min wage through is by sticking it in the $1.9 Trillion Covid relief bill, still languishing in the Senate.  Min wage clearly has nothing to do with Covid relief, but that's how they roll up there.  Anything to "never let a crisis go to waste," as Rahm Emmanuel famously opined.  The White House and the Evil Party senate leaders have been waiting to see how the Senate's parliamentarian opines on the wage increase and both Evil and Stupid party leaders are expected to meet with the parliamentarian tomorrow. 

A separate, popular story going around this week has been the waste and political kickbacks already in the $1.9 Trillion Covid relief bill.  “The Wall Street Journal editorial board estimated that only $825 billion was directly related to COVID-relief and $1 trillion was “expansions of progressive programs, pork, and unrelated policy changes.” (ZeroHedge)

The Evil Party's problems are first and foremost with their own members who are not lockstep with the extreme left side of the party.  As that quote from Politico mentions, Joe Manchin (D-WV) says he won't go to $15 but might sign on to $11/hr.  Manchin has previously said that an $11 minimum wage hike, adjusted for inflation, would make more sense for his home state of West Virginia. The other problem is Kyrsten Sinema (D-AZ) who has said she's opposed to putting anything into the Covid relief bill that isn't Covid relief.
“What’s important is whether or not it’s directly related to short-term Covid relief. And if it’s not, then I am not going to support it in this legislation,” Sinema said in a telephone interview this week. “The minimum wage provision is not appropriate for the reconciliation process. It is not a budget item. And it shouldn’t be in there.”
I find it shocking that there's someone in the Senate who thinks the rules matter and aren't just obstacles to maneuver around like Non Player Characters (NPC) and other obstacles in a video game. 

That's probably as meaningful a summary as I can provide.  Close to anything is possible in what they'll negotiate to increase the min wage; the Politico article includes perhaps a dozen possible things we'll see that various senators think could get by the parliamentarian.  Reliably RINO Senator Mitt Romney  and Tom Cotton of Arkansas talk about offering a higher min wage “while ensuring businesses cannot hire illegal immigrants.” (I thought this was already illegal).  Naturally Senator and Budget Chair Bernie Sanders thinks he's put a case together for the parliamentarian that will sail through and $15 minimum wage will be included in the Covid relief bill.  We'll have to wait to see how bad the results are.


Graeme Jennings/Pool via AP



Monday, February 22, 2021

Thursday's Mars Landing Video

Today, NASA/JPL-Caltech released a short video of the last few minutes of the flight of Perseverance to Mars, culminating in the landing.  If you haven't seen it, you should.

The world’s most intimate view of a Mars landing begins about 230 seconds after the spacecraft entered the Red Planet’s upper atmosphere at 12,500 mph (20,100 kph). The video opens in black, with the camera lens still covered within the parachute compartment. Within less than a second, the spacecraft’s parachute deploys and transforms from a compressed 18-by-26 inch (46-by-66 centimeter) cylinder of nylon, Technora, and Kevlar into a fully inflated 70.5-foot-wide (21.5-meter-wide) canopy – the largest ever sent to Mars. The tens of thousands of pounds of force that the parachute generates in such a short period stresses both the parachute and the vehicle.

“Now we finally have a front-row view to what we call ‘the seven minutes of terror’ while landing on Mars,” said Michael Watkins, director of NASA’s Jet Propulsion Laboratory in Southern California, which manages the mission for the agency. “From the explosive opening of the parachute to the landing rockets’ plume sending dust and debris flying at touchdown, it’s absolutely awe-inspiring.”
I have a tremendous amount of respect for the people involved in designing and pulling off this mission so far; not just the JPL but I'm approaching "five nines" (99.999%) sure that established defense and space contractors who are experienced with designing for space did much of the heavy lifting.  The levels of endurance, resilience, and reliability required in the electronics at every level is almost comical. This hardness is demanded from the components themselves, to the subsystems created, to the entire spacecraft and its auxiliary elements.  The running joke is that all the components used in space, "Class S" components, aren't considered acceptable until the test documents weigh more than the launch vehicle.  The testing should exhaust about half the components expected life (and they routinely work far longer than expected).   

I worked on one of those contracts for the JPL in the early '90s, and the JPL people exude an air of competence.  JPL has a desire to plan for every eventuality and asked rather amazing and dumbfounding questions.  Things like how a system might react when it was turned off if the systems it was connected with did something unexpected.  Most of us think our circuits won't do anything when they're turned off, but it's a worth looking at if the tests can be done.



If you're keeping an eye on SpaceX Boca Chica, you'll know that the expected static firing of SN10 (Sten?  Ted?) didn't happen today.  They have road closures tomorrow and Wednesday and FAA clearances to go for repeat of SN8 and 9's flight potentially as early as this week, although I kind of doubt it.  I don't know what went wrong today, but they didn't get as far as the cryo proof testing done in the last round of tests, judging by looking at the videos from late in the test.  There are never signs of the vehicle venting or getting icy, so it never got fueled. 




Sunday, February 21, 2021

Today, This Blog is 11 Years Old

That's right, it's my 11th blogiversary, and the rarest kind of anniversary: the day of the week and calendar date are the same.  My first post was Sunday, February 21, 2010.   Looking at that post, I'd have to say the more things change the more things stay insane. 


Stock photo from Depositphotos.

As always, I thank you for stopping by.  According to the stats engine on Blogger, my numbers have picked up in the last couple of months.  For years I'd get 1500 to 1600 views per day.  For the last month the eyeball average has been around 2500 to 3000 views/day; the lowest number of views in a day was 1947 and the highest was 4651.  Several times during the last month more than 3000 views registered.  I'm humbled and honored. 

The way those stats are provided makes it pretty much impossible to tell what people come here looking for.  

But that's old news.  What's going on now?  It appears that the power troubles are over at SpaceX in Texas, and the testing is going to pick up on SN10 this week.  Road closures are set for Monday through Wednesday and the fact that there are no flight restrictions (TFRs) implies that they'll try to achieve a static firing.  They need to do that before they can fly anyway, so I expect them to try in these next three days. 

Aside from that, Blue Origin and United Launch Alliance both showed some progress in the last week.  Blue Origin opened the hanger doors at their facility on the cape, showing a New Glenn apparently ready for some testing to start.  This is the first time a potentially real New Glenn has been seen by the public.  At the same time, ULA rolled their first prototype of their Vulcan rocket, the Vulcan Pathfinder, to launch complex 41 (SLC-41) on Cape Canaveral. 


Image by Twitter user Stephen C. Smith, photo editing by yours truly to remove some tilt and improve saturation.



Saturday, February 20, 2021

A Little Shop Update

In looking back over my previous posts, I notice I never updated the stories about my little Webster Internal Combustion Engine after showing the modification I made to reduce the amount the cylinder was moving.  I concluded that story saying, "Does it work?  I don't know.  I haven't had the time to test it, yet."  In fact, it does work, as this video dated February 3rd shows.  


If you compare this to the video posted on January 19th showing the engine running for the first time, the cylinder does lots of rocking back and forth in the first video.  In this video the rocking isn't perceptible. 

Since then, I've done little with the engine and had zero success getting it to start easier and run more reliably.  The only thing I've done that had any degree of success is putting together a new way of starting the engine.  What I had been using was a compromise to get me going quickly.  One of the guys told me about his method, which involved using a body shop tool called a pin stripe eraser. These things are large rubber wheels that are literally erasers.  It works but it's very messy.  Look below the flywheel's right edge in this video, between the two clamps, and you can see a mess of yellowish powder.  That's the eraser dust. 

The way most engine builders start an engine like this is with a pair of metal parts they make.  One is made for every engine and it's left on it.   It would help me explain to put the image here first.


There are two parts.  The one on the left slides over the crankshaft and is held by a setscrew visible near the left side rim.  I've seen these called a starter spud.  It's essentially a cup; a piece of 3/4 steel bored out to 1/2" inside diameter and about 0.150" thick on the bottom.  The bottom is reamed to match the crankshaft and installed so that the crankshaft fills the reamed hole.  The piece on the right is a piece of bronze rod I bought for the engine turned down to just under 3/8" diameter on the right end.  The piece is cross drilled and reamed to a 0.125" hole for a piece of 0.125 steel rod pressed in place.  It's a tight press fit; I had to use my mill's vise to push the pin into place.

To use these, the right side (I call it the Tee) is chucked in a drill, (my line powered drills are faster than my battery powered drill) the pin fitted into the slot and the drill is run to crank the engine.  In my case, it's done from the side you're looking at, and cranked counterclockwise. 

The good news is no eraser dust messing up everything.  The bad news is I still can't get the engine to start reliably and run better. 



Friday, February 19, 2021

Best By Date Rapidly Approaching

Light content tonight due to some family priorities.  The best by date may be here for this one.  


Another view of the Perseverance landing on Mars yesterday.


This is looking down onto the rover from Space Crane lowering Percy to the surface. 


An agate pulled from a river and cut open with a rock saw to see what's inside.  I believe from somewhere in Oregon but the link is long lost. 


From earlier this month right after the Game Stop/Hedge Fund fiasco blew up. 

As always, I save stuff that appeals to me while wandering the net. If it's yours and you don't want it used here or want a credit, just leave a comment or send an email; address in the "Contact Me" block in the right sidebar.



Thursday, February 18, 2021

NASA's Perseverance Rover Lands on Mars

The NASA/JPL team extended their record of successful landings on Mars this afternoon as the Perseverance rover landed at 3:55 PM Eastern.  All Mars landings are done autonomously because Mars is around 11 light minutes away from the Earth, making radio responses to command some maneuver arrive at least 22 minutes after they saw something they needed to do. The entire landing from the time they enter the atmosphere to touchdown is around seven minutes, making it impossible to pilot the spacecraft from Earth.   NASA famously refers to this as the "seven minutes of terror" because ground controllers can do nothing more than watch the telemetry coming back while hoping for the best.

In those seven minutes, simulated and subject to every Software Assurance test imaginable, they either successfully begin the mission, or spread a $2.5 billion work of art, engineering, and science across the surface of a distant and forbidding planet.

I found the summary that writer Eric Ralph at Teslarati pulled together to be a great perspective on those seven minutes.
The sheer insanity of injecting a car-sized rover into another planet’s atmosphere – with no prior braking of any kind – at around 10 times the speed of a bullet, deploying a house-sized parachute at supersonic velocities, and ultimately dropping that rover to the surface of Mars with a literal rocket-powered ‘sky crane’ is hard to exaggerate. The fact that that was what hundreds of the world’s smartest people concluded was the safest and most optimal architecture exemplifies just how extraordinarily difficult large-scale Mars landings really are.
This image captures the major milestones of the landing approach:


NASA/JPL-Caltech diagram of the landing sequence.

Note that at the end of the sequence, NASA uses the SkyCrane, in which part of the spacecraft separates and then lowers the rover onto the surface.  Once the landing is completed, the SkyCrane then flies away to dispose of itself.  This is only the second use of the SkyCrane method; the first was a sister Mars rover, Curiosity, still in operation on Mars.  

Perseverance is an innovative and ambitious mission.  It's the largest rover ever landed on another planet at 1025kg or 2255lb.s and among the ambitious parts of its mission is that it is carrying a helicopter drone to experiment with being able to fly the first vehicle on another planet.  There will be a chemistry experiment to determine if it's possible to extract oxygen from the Martian atmosphere's CO2, and perhaps most ambitious of all is a plan to collect interesting looking samples and store them for a follow up mission in perhaps 2028 to 2032 to retrieve and return to Earth. 

Within minutes of landing successfully, Perseverance took this image and sent it back to Earth.  We were warned it wasn't the resolution the rover will do, because the camera has a lens protector over it to protect it from dust and bigger pebbles scattered into the thin atmosphere, but here's our first look at Jezero Crater, where Perseverance will work. 





Wednesday, February 17, 2021

Bill Gates' Self-Serving Absurd Statement on Synthetic Meat

Everybody has been making fun of Bill Gates' almost comically wrong statement about eating synthetic meat.   Everybody talks about the easy quote, that the bottom 80% of income countries won't be eating synthetic meat, so rich countries should eat nothing but synthetic stuff.  You'll get used to the taste!  Honest!  But nobody has talked about the rest of the quote:
“Eventually, that green premium is modest enough that you can sort of change the [behavior of] people or use regulation to totally shift the demand.”
My turn to make fun of it. 

First off, how is this different from the Massachusetts environmental officer talking about breaking your will to keep you house warm in winter, or driving a car somewhere?  Gates is saying they're going to use regulation to break your will to eat meat.  The Masshole guy was forced out of office.  The only difference is that Gates isn't a public official who can be forced out of office. 

Gates' reason for breaking your will is that tired, old claim that cattle release too much methane, which everyone refers to as cattle farts when they're really burps, but the claim is disputed by actual agricultural scientists who have investigated it and is widely considered nonsense. 

One of the memes going around is that people say it's remarkable these companies take all sorts of plants and stuff and make it taste like beef, but cows must be smarter because they've been doing that forever.  When I say "all sorts of plants and stuff" I mean it: 


There's at least six ingredients in that list that I wouldn't put in my body, but the issue is deeper than that.  I actually did a blog post on this topic back in 2019 (two years and five days ago), which I'm going reproduce here. 

The Bullshit About Cattle Farts

If you pay attention to the Green New Deal and the incessant screaming from the vegan community, you'll think that cattle farts containing methane are the worst threat to the climate.  The UN has backed this lame idea before but their claims have some serious mistakes in them.  Mistakes or lies.  I have several good sources on that, but The BlazeTV released a short video of an interview with Dr. Sara Place, an academic researcher in animal science and sustainability.  This is only five minutes long and gives a good start.


First off, the methane from cows is 1.8% of the greenhouse gas emissions in the US.  Second off, methane doesn't come from cattle farts, it comes from cattle burps.  I realize that might be a minor distinction, but the EPA, those high priests of junk science, jumped on the "regulate cattle farts" bandwagon under Obama.  The UN claims cattle create 18% of global greenhouse gas emissions - more than comes from transportation - but they're lumping in all livestock, not just cattle, to include poultry, lamb and all sources of meat.  They're also including the effects of animal feed production, feed harvesting, feeding the animals, the farm vehicles that tend to these animals and everything up to the emissions from the slaughterhouse.  A third of that 18% is blamed on deforestation specifically in Brazil.

Both of those summaries are dishonest.  First, it's not fair to blame methane production in chicken farming on cattle farming, and it's unfair to include everything that the goes into food production to just the tailpipe emissions of vehicles rather than the equivalent entire life cycle associated with transportation.  Second, the part about deforestation is dishonest for two reasons; the easiest being that there's no equivalent deforestation in the US, or in other parts of the world.  In the US the story is reforestation.  We have more trees today than a hundred years ago.  The other reason is that not all grassland could be forest and not all forest can convert to grasslands.  There is some relation between the two, but it's not simple subtraction.  Simply, much of the planet can't be dense forest and can only be grassland. 

One of the most interesting videos from Ted talks about science is a 2013 talk about desertification by Allan Savory.  Dr. Savory talks about discovering that large herds of grass eating animals restore grasslands and reverse the damages to the environment.  Yes, herds of life stock "save the Earth".  It's a story of how a hundred years of following the agricultural scientists' best recommendations and removing livestock converted lush grassland to wastelands, and how reintroducing livestock has restored millions of hectares of that wasteland to productive grassland.  The before and after pictures toward the last few minutes of the video are jaw-dropping. 

Dr. Savory recommends eating the livestock, which naturally makes the the vegans haaaate him with a white hot, burning hate.

An interesting guy I've heard talk on this subject several times is Dr. Peter Ballerstedt, who calls himself a leader of the Ruminati.  He's an infrequent blogger, and regular speaker at various conferences.  Here's a quick summary of the basis for a new video, We Need A Ruminant Revolution.
Human beings exist because of ruminants. Today’s societies rely upon them. Humanity’s future depends upon improvements in the productivity and efficiency of worldwide ruminant animal agriculture. Like the general public’s confusion of what constitutes a “healthy diet,” tremendous misunderstanding exists regarding the environmental role of ruminant animals. Human beings didn’t evolve to eat meat, they evolved because they ate meat - and because they learned to cook and process meat and other foodstuffs. Unsurprisingly then, diets rich in butter, meat and cheese have been shown to promote human health and development. Of significant worldwide impact, such diets can correct the symptoms of metabolic syndrome, offering hope in arresting the current worldwide epidemic of chronic diseases.
The dire predictions from Anorexia Pistachio Kotex and her Democratic Socialists of America comrades that say we need to end cattle farts would be laughable without the need for a single fart joke.  Except it's not funny, it would kill many people and make the planet worse off because the planet needs livestock.  The planet needs ruminants.  You can say they were designed for each other or you can say they co-evolved this way, but the result is the same.  Like everything the socialists say, this argument is demonstrably wrong.

I think I'll leave the last words to an MD who advocates for high quality meats and minimally processed foods (which that synthetic meat is most certainly not).




Tuesday, February 16, 2021

When What Was Once Impossible Becomes Routine

It's a very, very common thing in the world.  Some high tech pioneer takes on something that was impossible forever, and then it wasn't anymore.  Then it becomes commonplace until nobody notices it anymore.  This connection you're reading over is an easy example.  So is radio.  Airline travel is another.  You can get on a jet, fly across the country staring out the window and everything below you is socked in clouds.  You spend five hours in the air and not see a thing until you make out the runway through clouds or fog and the airplane settling onto it.  No one thinks for a minute how that was done decades before GPS in our phones.

We had another example late last night Eastern time. SpaceX launched a much delayed Starlink mission to put another 60 satellites in orbit.  For the first time in 24 missions, they failed to recover the booster.  Booster B1059 was on its sixth flight, and the important part of its mission, getting the satellites to the right place for the second stage to do its job, was completely nominal.  The satellites were successfully delivered to the proper orbit. 

As a long time observer of these missions, there was a moment that just didn't look right.  There are two engine burns during the landing maneuvers of the Falcon 9.  The first is fairly high up and around 90 seconds before the landing, called the Entry Burn.  Three engines are lit and burn for 20 to 30 seconds.  After the engines shut down there was extra light, looking like either the shutdown didn't work as planned or something worse was going on.  This screen capture is from the mission video, within a few seconds after the shutdown and the booster view is on the left.  There's light shining toward the right, behind the grid fin, that shouldn't be there.  This long after the engines are supposed to be off, that left half of the video should have gone completely dark.  The right side is the second stage engine glowing reddish white hot, as they always do.  


About a minute later, when the landing burn and touchdown on recovery drone Of Course I Still Love You were supposed to be happening, the only thing that could be seen was an orange glow off in the distance.


Those white things on deck in the left side image are seagulls that can be watched moving around as the booster was supposed to be approaching.  I recall thinking those were going to be toasted pretty soon and wondered if they could react fast enough to get out of the way but they were spared. 

As of this evening, this is still the most recent news I can find.  There was to be a launch of another load of 60 Starlink satellites tonight, just under 26 hours after last night's launch, but that has been delayed until NET than Thursday night (Friday the 19th, @ 0512 in the morning UTC or 12:12 AM EST).  One would assume the delay would be to go over all the telemetry to see if that booster should be checked for some problem. 

SpaceX has always stressed on its video coverage that recovering the booster is not the important part of the mission, delivering the payload is.  They've said they expect to lose a small percentage of boosters for drone ship landings.  We've just all gotten so used to watching the booster land in the center of the drone ships' decks that it's a surprise when it turns out this rocket science stuff is actually hard after all.



Monday, February 15, 2021

The Long March to Peak Stupidity

The first month of the Biden (Jo/Ho) administration has seen proposals, executive orders, and proposed legislation that's staggeringly out of touch with reality.  From the absurd ideas of making middle and lower class taxpayers pay for the college of the doctors and lawyers (let's be real, the highest amounts of college debt aren't from Starbucks Baristas with a degree in aggrieved minority studies, they're from professional schools) to killing off America's energy independence and lots of good paying jobs, to today's gun control nonsense, they just keep going farther and farther down the road to unreality.   

I tell myself that they can't possibly be at peak stupidity yet because they've hardly started. Today, I see the latest bright idea is give a refundable tax credit of up to $1,500 on the purchase of a new bicycle.  Not just any bike, this is for an electric-motor driven bike, also known as an e-bike. 

If you're a long term reader, you probably know I'm a cyclist; I don't talk about it much, but have posted on occasion.  While I've looked at e-bikes now and then and know a guy who rides one all the time, my bike is low tech: if I don't push the pedals it doesn't go anywhere.  My friend's bike is the kind that is electric assist.  If he doesn't pedal, it doesn't assist, and he used it to much benefit preparing for hip replacement.  Even coming from the bike world, this is a stunningly stupid policy proposal. 
Authored by Congressmen Jimmy Panetta (D-Calif.) and Earl Blumenauer (D-Ore.), the Electric Bicycle Incentive Kickstart for the Environment (E-BIKE) Act supports the use of e-bikes as a zero-carbon transportation mode. Compared to other transportation modes, the bill recommends e-bikes because they are more affordable and accessible.

“E-bikes are not just a fad for a select few; they are a legitimate and practical form of transportation that can help reduce our carbon emissions,” Panetta said. “My legislation will make it easier for more people from all socio-economic levels to own e-bikes and contribute to cutting our carbon output. By incentivizing the use of electric bicycles to replace car trips through a consumer tax credit, we cannot only encourage more Americans to transition to greener modes of transportation, but also help fight the climate crisis.”
Where to start?  How much do you want to bet that Congressmen Panetta and Blumenauer come from districts that have e-bike manufacturers, or have other incentives?  Second, e-bikes are not "zero-carbon" transportation.  The energy that charges the batteries is coming from the power company.  Is it natural gas?  Is it coal?  Owners have no control over that.  But look a little deeper.  Even my bike, powered by me, isn't zero-carbon.  I give off carbon dioxide all the time, and more when working harder riding the bike.  An e-bike would be lower in carbon emissions than a car, but it's not zero. 

Although I've seen many tables of calories per hour a cyclist burns, depending on speed (and a host of assumptions), I've never seen numbers for the energy supplied by the rider and the e-bike to compare to the car.  When I first returned to riding as an adult in the early '90s, there was factoid spread around that the average bike rider riding 15 miles would burn around 600 calories, while a car would burn about 15,000.  That implied the car would burn about 1/2 gallon of gas to go 15 miles - 30 MPG around town - a pretty efficient car.  My 11 year old Explorer doesn't get 15mpg around town, more like 14.  It would use over 30,000 calories to go 15 miles. I'd use more like 690 on my bike.  

The bill would create a refundable tax credit up to $1500 for 30% of the purchase price of a new e-bike (that maximum credit is on a $5000 bike).  Note that says e-bike and specifically does not include tax credits for a human powered bike.  An e-bike isn't carbon-free, it's just lower carbon.  The energy to get someplace comes from somewhere.  It either comes from petroleum products, those same petroleum products converted to electricity, or it comes from the rider's body, converted from food.  They're trying to bribe people to give up using their cars by giving them some cash.  For a more modest bike, like this one, a quick check tells me the credit would be $780.  That check starts looking less good when it has rained, or snowed or any other sort of inclement weather.

A Townie Go! now from Trek Bikes, one of the most popular brands and models of e-bikes (although I gather this picture is an older model.  Just grabbed a stock photo.)  The battery pack (where it says "townie") is less obvious than the models that have a large, black plastic battery pack there.

It's a dumb idea based on the concept of a Weather Tax that I've dismissed years ago.  The only thing the idea has going for it is that the real cost will probably be low.  There will be a few people who take advantage of it but I can't imagine it will be many.



Sunday, February 14, 2021

A Ham Radio Series 21 - A Little Getting Started on HF Information

Most of the getting started information that I see is based on VHF radios, like the ubiquitous Baofeng VHF HTs (Handie Talkies).  There's nothing wrong with that, but since I've been more interested in High Frequency bands (HF - also known as shortwave), I see a few things that should get some mention. 

There are currently nine bands in the HF spectrum from 3 to 30 MHz.  These are referred to by wavelength, a tradition that's a bit odd when you realize the wavelength the bands are named for appears in exactly one of the bands. 
  • 80 m: 3.50 to 4.00  MHz (80m itself is 3.75 MHz)
  • 60 m: five assigned channels at 5.332 to 5.405 MHz (60 m is 5.00 MHz)
  • 40 m: 7.00 to 7.30  MHz (40m is 7.50 MHz)
  • 30 m: 10.10 to 10.15 MHz (CW & data only) (30m is 10.00 MHz)
  • 20 m: 14.00  14.35 MHz (20m is 15.00MHz
  • 17 m: 18.068 to 18.168 MHz (17m is 17.647 MHz)
  • 15 m: 21.00 to 21.45 MHz (15m is 20 MHz)
  • 12 m: 24.89 to 24.99 MHz (12m is 25 MHz)
  • 10 m: 28.00 to 29.70 MHz (10m is 30 MHz)
As we've pointed out in some of the various antenna posts over the years, antennas work best when they're cut to a specific length for the desired frequency, called being resonant.  The only useful thing about referring to the bands by wavelength is it gives you some feel for how big those antennas should be.  (A half wave antenna for 40 meters is 20 meters long).  For statesiders, you only need to remember one of the following two equations.  A quarter wave wire, in feet is given by L = 234/freq (where frequency is in MHz) while a half wave is twice that or L = 468/freq.  That number is already compensated for the "end effect" of cutting off the wire and wrapping a little into a loop to mount the antenna.  It's about 5% shorter than the wavelength in free space.


You can get one of these charts in many places.  Keep one near your radio.  I do. 

I can tell you based on years of operating all those bands that they all have distinctive behaviors and distinctive groups that hang out on them all the time.  How do you choose which one you might want to start operating on?  There are websites (like this one) that give you an overview of what to expect on each band, and you can listen around  Do you need a separate antenna for each band?  Do you need to run separate cables from each antenna into your station? 

You don't have to have a separate antenna for every band, but it's not that hard to get an acceptable signal on all of those bands with one antenna, like a multiband vertical.  Perhaps you might put up a wire for one or all of the lower bands (80, 40 or 30m) and a triband antenna for 20,15 and 10m - most of the spectrum on just two antennas.

For many years in this house, my low band antenna was an Off Center Fed Dipole, OCFD, cut for 40m.  OCFD means the dipole was a normal half wave long (468/7.1 or 65.9 feet total length), but instead of the coax being attached at the middle, about 33 feet from each end, I attached the coax at about half of that from one end or 16.5' from one and left the other end 49.4' long.  That changed the antenna so that one side was 1/8 wave long and the other 3/8 wave long.  Because of that asymmetry, a balun (balanced to unbalanced transformer) isn't needed, however something I read convinced me to use a transformer to 450 ohms at the feedpoint (that's 9:1 impedance or 3:1 turns ratios).  A 3:1 restricted range antenna tuner, like the big radio companies tend to put in their radios, tuned it on every band from 40 to 6m. 

There's almost an unlimited number of ways to solve the antenna problem.  A fan array is an easy antenna to make: it's a group of dipoles cut to frequency and tied together at one feed point.  The wires are kept spaced apart with plastic insulators, and since the impedances of the off band antennas are so wrong for the transmit signal, they don't interact.  For example, if you're on 20m the 80, 40 and 10m dipoles don't absorb much power because they're very wrong impedances.  


The hidden bonus here is that half wave antennas resonate on odd harmonics.  That adds coverage on 15m as the third harmonic of 40m, (that is, frequencies in the 40 band multiplied by 3 are in the 15 meter band) so although you see four wires, it's a five band antenna.  Yes, I've used one of these, a bit over 35 years ago.  It worked fine. 

Another standard antenna is an end-fed wire.  These are called Zepp antennas because it was the type used when Zeppelins were the aircraft of the day.  End fed half waves are high impedance, but friends tell me their end-fed wires work fine with an antenna tuner.  Antenna tuners were covered early in this series, more of a "how they work" than things to care about or watch out for. 

The major thing to watch out for when using an antenna tuner anywhere in your system is that the best place for the tuner is at the antenna feed point.  That tends to be really inconvenient, and the most convenient place is in the shack.  The price you pay for that convenience is more loss in the transmission lines as the signal bounces back and forth due to the mismatch.  Which says if you're going to scrimp anywhere, the coax might not be the place.  The loss in a piece of coax is a stronger function of diameter than the dielectric (insulators) used, so RG-8 or RG-213 is better than the smaller RG-58.  Which matters more for long cable runs than short pieces of cable.