Author Archives: Tom

Improving ARP performance on slow AX.25 links

Recently I’ve been setting up TCP/IP connections over VHF radio. They are Linux systems linked by 1200 baud AX.25 modems. Opinions vary as to whether the overheads of TCP/IP are worthwhile at 1200 baud—9600 is certainly better—but it’s handy and … Continue reading

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Making the CW filter work on an FT-817ND

I recently ordered a lovely 500 Hz mechanical filter to use for CW on my FT-897 and FT-817—the YF-122C. I was baffled for much of this week because I could not make it work in the FT-817. If I changed … Continue reading

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Sending JSON over websockets in Rust

I like the JSON format but I feel it’s important to contain it to the job of passing a message from one system to another. Ideally the sender generates the text automatically from some strongly-typed object and the receiver does … Continue reading

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Operating Packet Radio on Debian

To experiment with packet radio there are some basic things I need to be able to do. I need to monitor all packets, including those not addressed to me. I need to send individual packets, including a particular digipeater path … Continue reading

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