Solar CDX

Reading a rotary encoder with ATmega328

There are a bewildering number of examples, libraries, and opinions about how to write routines to read values from a rotary encoder. I found one that that looked particularly elegant and easy to generalize, so adapted it to the Atmega328 that I’m using for my current project. I used a pretty popular rotary encoder, Adafruit […]

The Antananarivoduino

Blue LEDs make everything more spiffy.

With wintertime (and remember, it is winter where I am) comes soldering – I can spend more than ten minutes in the garage without being drenched in sweat. I have a three week travel break before going on summer leave, so I’m trying to wrap up various projects. […]

Solder Fan

This project arose from a sudden desire to stop inhaling solder smoke. I just got back from about three weeks of constant travel around Africa with a bad head cold, cough and sore throat. After being away, I was itching to solder up something, but didn’t want to push myself any closer to bronchitis. […]

Internet backup power

About the time I am wrapping up in the office, the sun has risen and people are getting into work on the East Coast of the United States. I leave early enough to get home so I can make teleconferences that start at 9 Eastern. I’d have quite a phone bill if I dialed […]

How my antenna switch became a loudspeaker

I envision having a few antennas: the hexbeam, the G5RV, lindenblads for 70cm and 2 satellite work, perhaps a vertical of some sort if I can figure out where to place it, and maybe some kind of beam antenna for six meters. To make all that work, I’ll need some sort of way to […]

Fried Power Supply

The original fuse (white tube, bottom left) after cutting away black heatshrink tubing.

As a public service message, I feel obliged to share the following nugget of wisdom: before plugging a tower computer into a 220V outlet, reach around to the back of the computer and make sure the input voltage select is 220. […]

JackYack Rev A

The Version A circuit laid out in Eagle CAD. Top of board view.

Back in October, I mentioned an open source keyer developed for the ATTINY 45 and requiring only a few components. The source code for the controller and an example schematic were uploaded to a repository. Subsequently, I decided to try my […]

A loading coil for 80m

As the days grow shorter with the approach of winter and activity shifts towards longer wavelengths, I took stock of my log and noticed that while I have racked up a reasonable number of contacts on 15, 20 and 40 meters, 80 meters lags far behind. I anticipate moving overseas in about six months, but […]

A tiny and open source CW keyer

While working on a new project, I had a choice of either plugging in the output of a free-standing CW keyer or embedding one into the project. I decided to go with the embedded keyer, but then had to either find or write one. K3NG has written a top-notch keyer based on the arduino platform. […]

The Crossed Bananas Display

Arguably, the crossed bananas display (CBD) was not the next most needed accessory in my shack. I mean, who needs a crossed bananas display, anyhow? Nonetheless, I built one, and it seems to be working.

The CBD is a tuning aid for frequency-shift keyed modes. At one time, these displays were particularly in vogue among […]