claprs

An APRS tracker that lives in your terminal. It reads the live APRS-IS stream (receive only) and shows you what is on the air near you, or one callsign you care about, with a top-style live table if you want one.

Install

With a Rust toolchain:

cargo install claprs

No Rust? Grab a prebuilt binary for macOS, Linux, or Windows from the releases page.

Or build from source:

git clone https://github.com/benwoody/claprs
cd claprs
cargo install --path .

Setup

claprs config set callsign W0ODL     # your call, for the APRS-IS login
claprs config set home 34.05,-118.24  # your lat,lon (here: Los Angeles, a busy APRS area)

Neither is strictly required. The login falls back to N0CALL, and you can always pass --from lat,lon. But setting them makes here and the distance column work without extra typing.

Using it

claprs here              # stations within 50 mi of home
claprs here -t           # same thing as a live, sortable table
claprs near 100 -t       # wider radius
claprs call W0ODL        # follow one callsign (all SSIDs)
claprs watch W0ODL-7 N5OQT -t
claprs feed              # raw live feed around home
claprs last W0ODL-10     # last known position via aprs.fi (needs a key)

Add -t to any of the live commands for the full-screen table. Once you are in it:

up/dn  move        s  sort (recent / distance)
/      search      t  cycle type (mobile / wx / fixed / ...)
enter  detail      o  open the station on aprs.fi
p      pause       q  quit

The --table (-t) view decodes positions as:

• a symbol emoji on each station
• colors rows by distance
• reads weather station data
• flashes new arrivals green.

The detail popup adds bearing from home and a short position trail so you can watch a mobile station move.

Drop the -t and you get the same decoded data as a scrolling log instead.

Add --raw to anything to see the untouched APRS-IS lines.

Config

Values are looked up in this order: command-line flag, then environment variable, then the config file.

key	config file	env var
callsign	callsign	CLAPRS_CALLSIGN
home	home	CLAPRS_HOME
server	server	CLAPRS_SERVER
aprs.fi key	aprsfi-key	APRSFI_API_KEY

claprs config path prints where the file lives, claprs config show prints the current values.

A free aprs.fi API key (https://aprs.fi/page/api) is only needed for last.

A note on APRS-IS

claprs connects receive only (passcode -1, so it physically cannot transmit), holds a single connection, and always sends a server-side filter. That is the normal, expected way to read from APRS-IS. last is the only command that touches the aprs.fi web API, which is rate limited, so use it for spot checks rather than in a loop.

License

MIT. See LICENSE.