Hi - I'm Jack, a researcher with the US National Cancer Institute. I am based in Antananarivo, Madagascar. This blog is devoted to hobby items like amateur radio (my call sign: 5R8SV), electronics, computers and interactive fiction.

Solar CDX

Weller: The Final Chapter

Well, I hope it is the final chapter. I’ve written before about fixing and then learning that I hadn’t quite fixed my Weller WESD51 digital soldering iron. After much manipulation, I think I ended up cooking the PIC chip on the PC board, so I just ordered another board. Long story short: replacing the old […]

The Ginger Polygraph

The frequently lit red light indicates that our dog is lying.

My dog Ginger has a problem: she really likes food. That, coupled with her uncanny ability to convince family members that she has not been fed adds up to an overweight dog. She is not particularly sensitive about the subject and besides, she […]

Weller WESD51 Evil Football Taunt

Fooled again.

You know how you never see negative results published? Well, here are some. Recently, I thought that I had used experimentation and logic to find a clever fix for my transiently functional solder station. For the entire day after I soldered in two capacitors, it worked beautifully. On, off. On, off. On, […]

Weller WESD51 Repair

My solder station, a WESD51 had become increasingly flaky over the last year – at times, it would fail to turn on. Flip the switch up and down a few times, and the digits would light up and the iron would heat; flip a few more and it would remain inert. Sometimes it would work […]

Wifi for the Garage

A look inside the Linksys WRT54GS router used in this project.

Propagation has been abysmal, so it’s time to hang out in garage and work on projects. One catch: the garage PC gave up the ghost about a month ago. The Windows 7 computer had been functioning for a few months as a wifi […]

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 […]