Monday, January 20, 2014

APRS digipeater with a Raspberry Pi

For Christmas this year I received a Raspberry Pi. This is one sweet little computer! I also asked for (and got) an TNC-X board that you build and then plug into the top of the Pi. I now have a fully-functional APRS I-Gate and fill-in Digipeater up and functional here on the south side of McLean County. The stats are remarkable...and after some fiddling, filtering, and optimization, I've got it working just like I want. There are a few wide-area digipeaters in the area, but not many I-gates. While digipeaters allow mobile or portable stations to get their packets out to a broader audience, an I-gate takes APRS traffic from the internet and puts it out on the RF. Likewise, it take RF traffic and puts it back on the internet. Using a program called aprx, I'm running a digipeater and I-gate all from the little Pi! A local member of the Central Illinois Radio Club (CIRC) had an Alinco 2m rig he wasn't using anymore. That, along with the homebrew j-pole antenna I built, makes for a pretty good station. I'm only 30' up in the air, but we're on a bit of a rise. I'm copying stations from up to 75km away.

Heyworth UHF repeater update

The KG9DW Repeater in Heyworth is up and running on the Tate and Lyle Grain Elevator! This puts the repeater up at about 200' AGL. I made a trip to Indiana this past weekend and I was able to work it from Champaign. That's a pretty good haul for a kludged together UHF ham repeater. The antenna is a 8 element Decibel antenna, with 9 to 11 DB of gain (depending on who you ask). The antenna was abandoned from a farm operation that moved to Nextel or phones or something. This made the move a near non-event. The only hard part was routing the coax into the pressurized room. The previous coax had been removed, and the hole had been filled in. A little chiseling (without a chisel) and I was in. I've been working guys all over McLean and Dewitt counties, and even some down into Logan county. Give a hollar anytime on 442.825+ 141.3PL.