python

By JonathanGuthrie, 27 March, 2021

Lots of things have happened with the keyer. I bought rotary encoders and had boards made and populated one and it works like a champ. Only one small error on the board, and it's in the silkscreen so I'm going to ignore it, although you can see it in the photo above. So, if you have an interest, how can you get your own keyer?

Well, start at OSHPark and get yourself some of the boards:

The source for the firmware is on Github

By JonathanGuthrie, 1 March, 2021

Well, I finally went and did it. I built the 6-meter quadrifilar helix I've been talking about for years. Okay, it's not quite done, I'm waiting for a decent pair of wire strippers to arrive, but a week ago I took a four-inch PVC pipe, some 3/8 inch dowels, some Romex, and adhesive and fabricated a QFH antenna. I used a short Python program I wrote to determine the dimensions and, well, I did it wrong. The short wire in what I built should be the long wire at the operating frequency, so the whole thing is too long for the 52 MHz design frequency.

By JonathanGuthrie, 12 May, 2019

I've been busy working on hardware and working at work, but I started to do some software at home that I kind of want to talk about. At least I want to write what I've discovered down where I can find it and who knows, maybe this will get picked up by a search engine and it might help someone else. In my last blog post, I talked about buying a HackRF One a few months ago, and I've been building a power amplifier for that. The first version of that power amplifier let the magic smoke out as soon as I powered it up, even before applying a signal to it.