Sam WN5C uses ChatGPT as an Emergency Elmer

Sam WN5C has been on the blog before.  Last year we covered his heroic use of a Michigan Mighty Mite at Thunderbird State Park:  https://soldersmoke.blogspot.com/2023/06/sam-wn5c-builds-michigan-mighty-mite.html

This time, Sam writes about a good  ham radio use for ChatGPT: 

Hope you’re doing well. Just a quick note: ChatGPT is turning out to be a great homebrewing tool for me.

My elmer has been swamped with family issues, so my basic questions (“can you explain this circuit for me”) and hard questions (“why doesn’t this circuit I built work?!”) that he usually responds to right away has been a bit delayed. I’m in the process of designing a 5-band QRP CW transceiver with a superhet receiver and SSB receive so I’m learning a bunch of new circuits.

 

I’ve hated the idea of AI as someone who writes a lot (it cheapens what I’ve spent my career trying to perfect!), but man it is smart. I can ask it all kinds of questions. For example, it helped me design a little IF amp last night and ensured I got my impedance matching right (it’s great for mashing up lots of circuits and ensuring they work together). I can ask it for suggestions on part types and values. It helps with Arduino code if you’re into that. You can use plain language but it does well with heavy jargon. And, which I find really cool, it will step you through troubleshooting. It teaches the math, too.

 

Anyway, you or your readers might find this helpful. Especially when one is building at 3 AM and needs an answer immediately.

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Thanks Sam! 

 

Tezukuri and Chappy Happy -- Amazing Videos on Homebrew Radio (from Japan?) - Another 40 Meter Direct Conversion Receiver

So around the time we were building 40 meter direct conversion receivers, someone else was doing something similar.  His product (above) is a lot nicer than ours.  He has an S-meter and a digital frequency readout.  But like ours, his is built on a wooden board.  FB OM.  

If you want to see what a direct conversion receiver can do, watch his video (above). 

I was really amazed to see him use a modified VFO from a Kenwood TS-820.  Not long ago Pete N6QW spotted one of these on e-bay and recommended that I buy it.  As with the Yaesu FT-101 VFOs, we bought it for the gears and reduction drives but ended up with the entire VFO circuit.  I now have one on my shelf, ready to go.  TRGHS. 

We are not sure who Chappy Happy is, but "Tezukuri" means "hand-made" in Japanese. The writing in the video descriptions are in Japanese, then Chinese. 

Here is the YouTube channel.  Amazing stuff here:  https://www.youtube.com/@chappyhappy3675  He is clearly a ham.  He even works on an old S-38.  Who is this guy? 

Basic Radio Circuitry -- a 1971 film

This 1971 training film is pretty good.  I like how they break the RF circuitry into just four components, then describe the AM receiver stage by stage.  The way they handle diode (envelope) detection is exactly right.  But their description of how mixing moves the incoming signal from the broadcast band to the IF is overly simple, and sort of just repeats the hetrodyne story from music. Real mixing is, of course, more complicated than that, but too complicated for a 15 minute film. 

Bill N2CQR Appears as a Guest on the Ham Radio Workbench Podcast

https://www.hamradioworkbench.com/podcast/hrwb-223-a-conversation-with-bill-meara-n2cqr-from-the-soldersmoke-podcast 

Partly in an effort to make ammends for some overly harsh comments I made about the podcast's approach to the "rejuvenation" of old radios (it turned out to be overly digital for me) I appeared earlier this month on the Ham Radio Workbench podcast.  It was a lot of fun. They are a great  bunch of guys.  And I think we had a great discussion of homebrewing and HDR in the modern era. We talked about Jean Shepherd, Farhan, G-QRP, kits vs. homebrew, homebrew vs. commercial, SDR rigs, the sBITX, the NORCAL 40, the Gilbert Cell Mixer, our experience (bad) trying to get high school kids to build a DC receiver, and many other topics. 

Thanks George!  And thanks to the entire Ham Radio Workbench crew!

Remember, SolderSmoke has issued a challenge to the HRWB team:  We challenge them to build the 40 meter Direct Conversion receiver that we designed for our local high school.  We urged them to build it the way we designed it -- avoid the temptation to substitute stages, or use pre-fab circuit boards.  Build the four stages Manhattan style and get the receiver working on 40.  Here are the details on how we did it.  Here are our building documents:

https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

The challenge has been issued.  The gauntlet is on the ground.  Go for it HRWB!  Put those workbenches to use! 

Video -- Mythbuster II Rig Gets a Front Panel -- Circuit Build Almost Done

Yesterday I built a front panel for my Mythbuster II 20 meter SSB transceiver. 

I used 1/8 inch plywood available from Amazon. 

I cut holes for the main tuning knob and dial, for the AF gain control, for the mic plug and for a 6 figure PLJ PIC frequency counter.   This gives me 100 Hz read capability, but I can hit the lower button on the counter to get 10 Hz reolution.  This may help when the other guy complains bitterly that I am 40 Hz off frequency.  The counter added noise to the receiver, but I was able to knock this down completely with a resistor and a cap on the power line to the counter. 

I put copper tape on the inside of the panel. 

I added a reverse polarity protection circuit.  I now sleep more soundly. 

I increased the size of the heat sink on my RD06 final.  This decrease the danger of blowing up this device. 

I added a jack for the connector that will switch the outboard .1 kW linear from R to T.  

Video above. Comments welcome.