Category: Ham Radio

Making My Own LM2596 5V DC-DC Step Down Converter

 

LM2596 CircuitI decided to have some fun and build my own down converter for my Raspberry Pi. On my first try I used a LM7805 but quickly realized it would not work with 14V and the TO-220 heatsink I had on hand. I saw some videos on the cheap Amazon/Chinese/eBay voltage down converters, and I really wasn’t impressed. They looked poorly made with copied LM2596’s and are probably very noisy, which isn’t good for my radios. I wanted quality and efficiency to use my Raspberry Pi on batteries, so with a few dollars worth of quality parts I managed to throw my own DC-DC step down converter together with the circuit design direct from Texas Instruments above. (more…)

Raspberry Pi Ham Radio #1 – WSPR

WSPR Command Line

Just a few days ago I bought a Raspberry Pi with nothing but the case and SD card expecting to just have it run as a little SSH server so I could remotely login to my weechat tmux instance, and upload weather data to wunderground from my weather station with weewx. I set everything up, tinkered around with it for a day or two and had it running smooth. I got curious and had heard in the past that the Raspberry Pi could be turned into a low power FM radio. Reading further, the Raspberry Pi actually does 1-250Mhz which is a perfect range for amateur radio operators. I knew it wouldn’t provide much power (10 dBm), so weak signal modes were what I needed. (more…)