Challenges Involved in Designing a Linear MOSFET Driver Stage

In the process of designing a linear driver stage to use as a a load, I came across this thread on the EE stackexchange detailing one guy’s design process and lessons learned doing this exact thing.

I’ve ended up using the STP75NF75 because it was the part that didn’t crater during testing. Since most MOSFETS are designed as switches making them operate in linear mode takes some doing.

The whole post links to the various threads that the author was asking questions in, and he has all of them annotated with lessons learned. It’s a quality post and interesting reading in its own right, and is worth reading even if you never want to go through this particular design exercise.

Oddball TL431 circuits

I came across this circuit in the “Typical Applications” section of the datasheet for the On Semiconductor version of the TL431 programmable voltage reference. I think you will agree that it’s definitely not “typical”.

Phono stage built using a TL431 voltage regulator

That’s some old skool Forrest Mims III out-of-the-box shit right there.

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December ISS SSTV event

The December SSTV Event from the Russian MAI-75 experiment in the International Space Station was not nearly as successful for me as my previous attempt, but I did manage  to snag a few decodes.

I used a Signalink this time instead of the generic $3 USB sound card I used last time, and despite some pretty awful QRM I was still happy with the results.

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SSTV from Spaaaacccce

As part of the 20th anniversary of amateur radio on the International Space Station (ISS) the crew broadcast a series of Slow Scan Television (SSTV) images from the Russian crew module. After several failed attempts (mostly due to my laptop’s sound card sucking) I managed to receive and decode this image:

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