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Hi, I'm Elijah Brown and welcome to my site, AD7ZJ.net! The name AD7ZJ is my ham radio callsign, and I occasionally post stuff I'm working on here for my own reference and for the benefit of anyone else who is interested.

Flying my Cessna 140 over Roosevelt lake

Electronics/Software Projects

Image taken off an ANSR flight from approximately 40,000 ft

I enjoy tinkering with electronics and software and I've done quite a few little side projects in this area. Here are the ones I remembered to write down and take pictures of :)

• OpenAWOS — Used at our glider field to automatically report wind over VHF radio.
• Vaisala 425A Anemometers — Used by my diy AWOS system above.
• Remote Cellular Switch — Used to turn on an engine pre-heater remotely.
• FLARM Teardown
• Stratus 1 Teardown
• Single Digit VFD Clock
• Single Digit IN-18 Nixie Clock
• Vocore Temperature Logger
• Voltage Regulator Tube Lights
• Iteris RZ-3 Cameras

Arizona Near Space Research (ANSR) flies unmanned high altitude balloons around Arizona both for fun/education of its members and in support of several college programs. I have been involved in the maintenance and design of the flight tracking beacons identified below. For general info on the club or on student payloads, please visit our main site ansr.org.

• Flight Computer 1.0 — The original ANSR flight computer and crossband repeater.
• Flight Computer 2.0 — Gen 2 of the flight computer. My first attempt at a non-trivial embedded project...
• PIC APRS Beacon — A simple APRS tracking beacon. My goal was to generate the AFSK output without a modem chip.

I have done a handful of projects related to ham radio and antennas. Here are a few of those - I think the magnetic loop is the most interesting. They are an excellent choice for HF if you are limited on space.

• Helical Magnetic Loop Antenna
• Maxon Data Radio info & repair
• DIY Current Meter — Just some pics and ideas
• VHF and UHF antennas — Some practical antenna construction tips

Mechanical Projects

I have been mechanically inclined for as long as I can remember. Unfortunately I often don't think to take pictures or keep track of stuff I've fixed or worked on, but here are a few highlights.

• ASW 15
• PIK 20B
• Cessna 140
• DIY Large Solar Tracker
• Small off-grid solar setups
• Chevy K1500 4L60E Transmission Rebuild

Misc Stuff

• Dump Windows Cert Authorities
• ATSAMV71 Microcontroller Notes
• OpenWRT expressVPN setup
• Convert MCS to BIN
• Raspberry pi notes
• KD7LMO Archive
• Useful links
• Honda CRF230F