APRS iGate - Serl Computer Research

As of 2017 I received my Amateur Radio license and wanted to explore aspects of data and Ham Radio. This brings my to build an APRS iGate to provide gateway services to the north end of Jurupa Valley.

Originally I build this using my Baofeng UV-82HP handheld but that meant that I had to shutdown the gateway whenever I needed to use my HT. Another radio was needed for a permanent installation. Luckily, APRS uses simplex for localized transmissions. This means that an older, far less desirable radio could be used. Radios build in the 80’s and early 90’s often lack the PL tones required for repeater use bringing their resale value way down.

This old Azden PCS-2000 radio was won on an eBay auction for $1 (plus shipping). This has proven to be a solid radio rated for 25W output. Far greater than the 8W output of the HandHeld!

Easy-Digi audio interface

A 2 Meter transceiver purchased for $1!

The Azden radio was missing the microphone so I drilled a hole in the top cover and connected the PSK-31 “Easy Digi” interface directly to the control board of the radio. A radio purchased for a dollar removes all romantic attachments! This unit lives in my garage and so far both the radio and little computer are dealing with the heat quite well.

My original use for the computer was for LiteCoin mining but the mining hardware really became useless with age. I cashed in my Coins at their peak value in early 2018 and recycled the PC.

Now the little HP machine runs APRSIS32 to gate packets received from the radio to the Internet. The addition of a cheap USB sound card gives additional isolation for the software modem to keep stray PC sounds from being broadcast on the radio.

As a last step, I wanted to have a permanent antenna for this installation. I build a 5/8 Wave ground plane antenna and mounted it to a rafter. Compared to the rollup J pole antenna I was using, the reception is still very good. I would like to get the antenna higher and outside but that will have to be later.