Sunday, January 1, 2023

Dwelling on a Meme

Irish posted this meme on Friday and I thought a few words might bring it to life.  

A couple of things.  

First, this would have been a dream station in the 1960s.  It's entirely Collins radio products.  Because of the similarity in appearance between receivers like the 75S-1, 75S-2 and 75S-3, for example or the transmitters that began with 32S, I can't tell you what exactly is in there.  There's a couple of their transceivers but, again, there are model numbers that are rather similar looking.  The big cabinet on the left is 30S-1 linear amplifier. With this resolution picture, it's hard for me guess what radios those are. 

All that aside, a station like this, perhaps 55 or 60 years old, is entirely capable of posting memes just like this picture with text.  From your computer to other computers.  Shitposting memes doesn't have to be done by talking into a microphone.  It requires a modulation mode that many of you may have never heard of: Slow Scan Television or SSTV.  Slow Scan is very often used in the High Frequency (shortwave) spectrum because it only requires an audio bandwidth channel (less than 3 kHz), as opposed to the roughly 5 MHz wide slice of spectrum that fast scan television uses.  Hams can also do fast scan television, at least in the US, if they do their transmissions in the UHF spectrum, which are relatively "wide open spaces." 

The difference between slow scan and fast scan is (brace yourself) speed.  The old analog TV (now obsolete) did 25 to 30 frames per second.  Slow scan sends one picture in more like 30 seconds.  The thing here is that "TV" in the name is a misnomer.  It's not moving pictures, it's more like a slide show.  TV sends nearly identical frames in those 30 frames/second, so they all have to be the same size.  With slow scan you can send different sizes.  Bigger pictures take more time.  

The drawback to SSTV is that an HF channel can change during that half minute or more and the image can get corrupted.  It's not an error-correcting protocol.  Nothing says one couldn't be developed; heck, there might some out there that I haven't heard of.  

Nowadays, most transmission and reception starts and ends in computer.  There are various pieces of software that will take a jpeg, like this meme, convert it to audio tones and send to another hams computer across town or literally anywhere on HF.  It has moved off desktop computers onto phones and tablets.  When I played around with SSTV some years ago, a popular PC program was freeware from a Japanese ham Makoto Mori, JE3HHT, called MMSSTV.  It's from the days of Windows 98.  This club does an introduction to the mode and demonstrates Android operating system SSTV.  Of course, any software like this is going to run under Apple's iOS, too

To interface the computer to the radio usually requires a small box that connects to the computer sound card on one end and to the radio's microphone and headphones on the other.  I haven't shopped for something like this for an old radio like these, so I don't have any manufacturers names to look for.



23 comments:

  1. I worked Army nets in Germany for 6+ years. We had 4 transceivers, 4 linear and a large antenna field. It was always NOISY!

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  2. I've been using MMSSTV since 'forever'. The latest Kubuntu upgrade nuked my installation of it, and that's the last issue I have with this upgrade. Great little program!

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    1. Most of my radio control stuff goes through Ham Radio Deluxe (HRD). It comes with a digital mode program call DM780 that I've done all sorts of modes with, RTTY, PSK31, Olivia, and more. It also does SSTV. To be honest, I never got that interested in the mode, but when I did my playing with it, I used MMSSTV. Got it running, exchanged a few pictures and that's about it.

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    2. I rarely send any pix with SSTV, but I've got dozens saved. I don't think there's a Linux equivalent to HRD, so I use separate apps.

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  3. Early Apollo used SSTV (developed by Hams) for their video, but dropped it in favor of higher-bandwidth video when S-band came online when the DSN equipment was upgraded. Still used, though!

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    1. Do you have any insight into what Apollo used for the Nixon live phone call?

      I'd like AT&T to use it so I can make a call in the sticks that is of the same vocal quality as 50 years ago.

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  4. Mid-80s we used UHF fast scan to try to feed weather radar from the TV station to the EOC and to SKYWARN spotters in the field. Unfortunately we needed an amplifier we didn't have funds to buy to give it enough range to make it practical. Then mobile internet came along and made it obsolete in a manner of speaking.

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  5. If God was a ham, this could be His shack. And if the broadcast station call sign is indicative of the QTH, God lives in Amarillo.

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    1. Smack my head! I can't tell you how many times I studied that picture trying to figure out what mix of rigs that was and never noticed the enormous KGNC sign! D'oh!

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    2. I didn't see the KGNC sign either, and I used to be the chief engineer there.

      I have a strong suspicion who's shack that may have been. I used to work with the gentleman at KAMR-TV. Originally Globe News Company in Amarillo owned KGNC AM, FM, & TV. When the FCC ownership rules changed, they were forced to divest the TV which became KAMR.

      Their main transmitter engineer was Jim (James) Reese. He was a Ham operator and was one of the people who encouraged me to get my Ham license. He was one of the nicest people I have ever known. I never had the opportunity to see his shack, but if memory serves me correctly, he did like Collins gear. He had been an engineer for DuMont way back when they made transmitters, so he knew tube equipment inside out.

      1980 callbook:
      W5TCY James G Reese

      I was not aware of any of the other KGNC or former KGNC employees being Ham operators, but I can't rule out the possibility either.

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  6. To the untrained eye, that is a pretty impressive rig. Also interesting (and good) to know that ways around systems still exist.

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    1. There are several stations in that picture. Since I can't quite resolve what the models are, I see at least three transceivers - add a speaker and microphone and they're three full stations. There might be six stations. It's a very expensive way to replace a band switch, but the operator could change bands by swapping radios.

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  7. I had a Collins setup for long range commo in my army unit. I would have to look through my 201 file to determine what it was since it was assigned to my equipment inventory. From what I remember it was AM/SSB, seperate transmitter and receiver, a linear amp, and power unit. We had a long wire antenna for it.

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  8. Think what you will about Alex Jones, when he got deplatformed by the feds working with social media companies, he was still available 5 nights a week on shortwave. Had he not had that, and (likely, although I never bothered to look) some off-shore servers, they would have silenced him. I'm surprised they didn't go after him with tax law, and only used lawfare...

    (and I don't think anyone is interested in debating Alex Jones, I just bring it up because FOR HIM shortwave radio has been an important backup. FOR HIS LISTENERS it has the added benefit of not being trackable.)

    I'm thinking someone needs to set up a BBS service accessible by radio and hosted off-shore... like the old school dial ups.

    Backups and contingencies are a GOOD thing.
    n

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    1. Hams had the world's largest digital radio network in the world. It was called Packet Radio.

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  9. I still love the look at these boat anchors, and the feel of their switches and controls over todays digital sdr rigs. Back in the sixties I remember having discussions with friends on future radio designs and miniturization of things. We figured that radios would get so small and light the makers would have to put lead weights in them to stop the radio from flipping over when the band switch was turned. Of course PC designs were not yet envisioned. For this old timer theres still nothing like the smell of tube rigs or test equipment warming up as the varnish and phenolic insulators outgas that perfume.

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    1. I don't think any of us envisioned color LCD screens with touch sensitive controls, or radios that were so small they had to nest menus three button pushes deep.

      Our running joke is that my mil surplus R-390A general coverage receiver holds down that end of the house. It's 65 lbs. I have a Collins KWM-2 transceiver on my bench and while it does everything that the more modern radios do, the operating conveniences in the newer radios are stunning. Having adjustable IF filter bandwidths - set an IF filter BW while you listen and they all behave like "brick wall" crystal filters - is just amazing. Still, I hardly ever do that.

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    2. The filtering in my FTdx-101 is astounding. The learning curve is equally steep to get the most out of it, but worth it.

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    3. I was a senior field engineer for Rockwell Collins on their earth station satellite install just before the breakup of the company. Diversity killed the company.

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  10. I don't have any old Collins equipment, but I do still have some old Hallicrafters boat anchors. Real radios glow in the dark.

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  11. There is a Collins virtual musuem at the link. Lots of history, publications, etc.

    https://collinsaerospacemuseum.org/

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    1. Thanks for that, Fladave. Bookmarked.

      It also included a link to a site dedicated to Art Collins .


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