The Transistor that Changed the World -- the MOSFET

Another great video from Asianometry.  

My only quibble is that it kind of left unclear the differences between JFETs and MOSFETs.  After all, we still use both.  Note our beloved J310 JFET.  And the IRF510 is a MOSFET.  

Google's AI explains: 

A JFET (Junction Field-Effect Transistor) and a MOSFET (Metal Oxide Semiconductor Field-Effect Transistor) are both types of field-effect transistors, but the key difference is that in a JFET, the channel conductivity is controlled by a reverse-biased PN junction, while in a MOSFET, it's controlled by an electric field across an insulating layer between the gate and the channel, allowing for a much higher input impedance and greater design flexibility in MOSFETs; essentially, MOSFETs are considered a more advanced version of JFETs with superior performance in many applications like high-speed switching and integration into complex circuits. 

Tally Ho! Leo Solders -- Aurora -- Satellites -- Meteors -- Tides -- Starlink

I've been following this YouTube channel, probably since early in the pandemic.  It is not about radio, but in this episode we see Leo actually do some soldering.  NOT BAD!   Lots of other related stuff.  

Here is the YouTube channel: https://www.youtube.com/@SampsonBoatCo

What Happened to the SolderSmoke Blog?

 

The conclusions of this article ring true, but I am not certain that changes to the Google algorithm, or the introduction of AI answers to Google queries explain the changes that are reflected in the above chart. 

Here's the article: 

https://www.bbc.com/future/article/20240524-how-googles-new-algorithm-will-shape-your-internet

Take a look at the traffic going to the SolderSmoke blog over the last year (see chart above). 

Something bad happened to us around April 15.  

What do you guys think?  What happened? 

MIT Looks at the Artificial Intelligence Podcasts of NotebookLM

https://www.technologyreview.com/2024/10/03/1104978/people-are-using-google-study-software-to-make-ai-podcasts-and-theyre-weird-and-amazing/

4Z4GE's Homebrew Tube SSB Transmitter from Israel, 1974

https://www.nzeldes.com/Miscellany/SSB-rig.htm 

Very cool. I like his description of how he found parts for this transmitter:  

The power amplifier tubes needed ventilation as well as shielding; that was always a challenge because I had no good source of perforated metal. The black sheet with the round holes actually came from the cover of a car air filter that I found in the trash.

There is a lot more interesting stuff on Nathan Zelde 4Z4GE's site: 

https://www.nzeldes.com/possiblyinteresting.htm

Thanks Nathan! 

Homebrew Receiver -- AG5VG's 20 Meter "Mythbuster" Receiver

Michael has the receiver done and is wisely heeding Farhan's advice about pausing to enjoy the homebrew sounds.  

I was pleased to see someone else using the FT-101 VFO.  Great piece of gear.  

On to the transmitter!  

Fernando's Rigs -- Vintage Ham Radio Receivers

Thanks to Rogier PA1ZZ for sending me this YouTube link.  It is a truly wonderful channel from Spain. Not only the Collins Gold Dust Twins, but also lots of great (and not-so-great!) older receivers.  SP-600s, S-38s,  Rhode and Schwartz rigs, lots of great stuff.  Go to the "Videos" link and enjoy the Thermatron goodness.   Thanks Rogier!  And thanks Fernando! 

 https://www.youtube.com/@jonglei

SolderSmoke Artificial Intelligence -- Where the AI Podcasts Came From

 

The aticle and the podcast (don't worry, it is NOT an AI podcast) explain how we were able to generate the AI podcasts we presented during the last two days. 

https://www.theverge.com/24249388/notebooklm-google-steven-johnson-vergecast

The audio podcast feature was introduced only ONE WEEK AGO!  Rarely have we been so close to the cutting edge!  

The product itself first launched in 2023 as Project Tailwind, and has since been rebranded and expanded in big ways. Just last week, the team launched Audio Overviews, which generates a podcast — with two chatty hosts, plenty of back and forth, and a truly remarkable penchant for the phrases “deep dive” and “buckle up” — based on the information you provide. It’s fascinating, it’s complicated, and it’s getting better really fast.

Thanks to Bob for alerting me to all this! 

AI Podcast #2: Here is Another Short Podcast ABOUT SolderSmoke.

Click here for the second "About SolderSmoke" podcast. 

 http://www.soldersmoke.com/About SolderSmoke 2.mp3

This one looks not at the SolderSmoke Daily News blog, but instead at the SolderSmoke podcast itself.

I was delighted to see the inclusion of Pete, Dean, Farhan and Mike Rainey!   This was really great.  

Look, it is not perfect.  There are errors.  But probably about the same number of errors that you would get from real, human hosts, right?    Voltaire told us not to let the perfect be the enemy of the good.  And I find this to be amazingly good. Look, it is so good that it is kind of scary, right?

Before you get too critical realize how this has been done:  I did nothing more than load the SolderSmoke Podcast Archive website into GPT-like model. Then I asked it to produce a deep dive podcast.  That's it.  About 5 clicks.  It developed the podcast in about 3 minutes.  I did the same thing yesterday but with the SolderSmoke blog.  And this is only the beginning.  

AI Podcast #1 -- A new (experimental) Podcast About SolderSmoke Daily News

GET THOSE SOLDERING IRONS HEATED UP!  WE'RE GOING DEEP TODAY, DEEP INTO THE WORLD OF HAM RADIO! 

Click here for the new experimental podcast: 

http://www.soldersmoke.com/About SolderSmoke 1.mp3

I am looking for comments on this.  What do you think?  

Please post comments below or send me an e-mail. 

Thanks and 73 

A Clean Vintage Ham Radio Transmitter: The Collins 32S-3

In an article on IMD and splatter,  tech guru Rob Sherwood noted that the cleanest tranmitter he had ever owened was the Colling 32S-3.   Here is the article.  https://soldersmoke.blogspot.com/2024/09/sherwood-its-time-to-clean-up-our.html

In it, you will see thar Rob has the spectrum anayser two tone test to prove his point.  

This got me wondering:  Why was the Collins transmitter so clean.   Today I looked at some ot the tech info on this rig.  I think I have found the answer. The Collins Collectors Association has a great page on the 32S-3: https://collinsradio.org/cca-collins-historical-archives/the-equipment-of-collins-radio/the-grey-boxes/32s-3/

The key lines are these:  

Click on the paragraphs or go to the link for a clearer view 

I think the explanation of Collins'32S-3 cleanliness is due to 1) Thermatrons in the final stages and 2) Negative feedback to take down any IMD products that might appear due to non-linearities in the finals.   

There is nothing magical in that technique.  Heck, we could homebrew that today.  We could build HDR stations (perhaps transistor-tube hybrids) that would be cleaner than their commercial SDR cousins. 

Ham Radio -- How To Build Stable Oscillators

Spasibo Vasily!  

Wow, thanks a lot Todd.   There is some great wisdom in your video.  You clearly demonstrate that it is possible to build your own stable LC VFOs.  Sure, for many the arrival of the synthesizer chip put an end to this kind of project.  But some of us still want to fully homebrew all the stages in our rigs, and not be dependent on mysterious chips and software written by others.  

I really liked the way Todd acknowedged the tremendous contributions of Wes, and Roy, and Rick and others. 

Of course, all of Todd's recommendations are right on the mark.  I have been following most of them (but I do fall short and occassionally use a Manhattan pad or two).  Todd even gets into the mysterious and arcane practice of boiling (three times!) toroidal transformers.  I do have a preference for air-core coils, but that boiling sounds like fun. 

One thing that Todd and Brad might also want to consider:   tuning linearity.  Too often LC VFOs end up having the frequency spacing very close at one end of the dial and very broad at the other end.  "Bob's Electron Bunker" provides some great tools for alleviating this problem:

https://soldersmoke.blogspot.com/2022/09/the-cure-for-frequency-bunching-up-in.html

Thanks again Todd!