Richard Fakenberg (OK1BR)

OK1BR · CW, contesting, homebrew. Building the native Linux ham stack I wanted to exist: SDR, skimmer, logbook — all in C/GTK4, no Wine. JO60TD

[Richard Fakenberg (OK1BR) @ok1br]

Three native Linux apps for ham radio, in C and GTK4:

sdr-for-linux — SDR transceiver
skimmer-for-linux — CW skimmer
log-for-linux — contest logbook

One family, linked over TCI. Built and proven on the air, in real contests.

https://t.co/psNnUTaLfZ

73 de OK1BR #hamradio

[Richard Fakenberg (OK1BR) @ok1br]

skimmer-for-linux 0.5.0 ships the neural CW engine I ran live through SAC CW this weekend, on GPU or CPU. On a 20 m recording it pulls 10 stations where the classical decoder finds 7, and it now keeps its callsign dictionary current on its own.

#hamradio #cw #sdr #linux

[Richard Fakenberg (OK1BR) @ok1br]

@StudioXRadio That's the beauty of Linux and open source. Don't like something? One prompt to an AI agent is all it takes.

[Richard Fakenberg (OK1BR) @ok1br]

A graphics card copying Morse live in SAC CW.
DeepCW neural decoder (model by e04) in skimmer-for-linux on RTX 5070: 1536 channels over 192 kHz of 20 m, ~90 stations tabled while I log.
First contest hour: 4 bugs the recordings missed.
73 de OK1BR
#hamradio #cw #contesting #linux

[Richard Fakenberg (OK1BR) @ok1br]

At YO DX HF I never counted my score. The logbook knew every QSO, it just never added them up.

log-for-linux 0.3.1 counts it live: points × mults.
Plus, YO county CT and Portugal fought over one mult.
New SAC preset for the weekend.

73 de OK1BR
#hamradio #cw #linux #archlinux

[Richard Fakenberg (OK1BR) @ok1br]

@StudioXRadio The red edges come from the same passband function the TX DSP uses, redrawn every frame from mode + TX filter (not the RX one), so they can't drift. Clip below. The G2E is my dev rig and I love it. Only nit: the fan, audible even with a Noctua; thinking temp control. 73

[Richard Fakenberg (OK1BR) @ok1br]

Two VFOs, A/B and A=B. Yes, my SDR app only just learned that.

sdr-for-linux 0.5.1 also brings CTUN, filter edges you drag right on the spectrum, and the TX passband drawn in red. Tested live on the ANAN G2E for a week.

73 de OK1BR
#hamradio #sdr #linux #archlinux

[Richard Fakenberg (OK1BR) @ok1br]

@StudioXRadio Omarchy is nice, but a tiling WM doesn't really suit me. I prefer plain Arch with a GNOME desktop I've modified myself.

What exactly do you mean by passband drawing? The spectrum display during TX, the drawing of the filter itself, or adjusting the filter? 73

[Richard Fakenberg (OK1BR) @ok1br]

@StudioXRadio Around hams since childhood, thanks to my dad. Same for 30 years: some try everything first, some take advice once they see they're behind, and some would do it all with pencil and paper and knock anything new so they don't feel dumb. Do what you enjoy, don't get discouraged. 73

[Richard Fakenberg (OK1BR) @ok1br]

@StudioXRadio Start at 192 kHz, receiver 0 on a CW segment: all my numbers are at 192k, and the skimmer takes the rate from each block. One mismatch: TCI 2.0 has channels in header word 7 (Thetis sends 2). Zeus leaves it 0, so the skimmer drops every block. One line either side. 73

[Richard Fakenberg (OK1BR) @ok1br]

My CW skimmer only ever knew one TCI server: mine. Then SM0ONR aimed it at a SunSDR.

Connected. Silence.

BW to 156 kHz: waterfall, decodes, spots on the ExpertSDR3 panorama.

skimmer-for-linux 0.4.1 drops 5 assumptions only mine met.

73 de OK1BR
#hamradio #cw #sdr #linux

[Richard Fakenberg (OK1BR) @ok1br]

@StudioXRadio Five, all from testing against only my server: IQ as one byte stream across WS messages (now one block per message), no receiver filter on h[0], stamps from reserved words without the iq_stamp echo, three commands in one frame, a fixed port. Any of these bite Zeus too? 73

[Richard Fakenberg (OK1BR) @ok1br]

@AjithN628302 No Android version, sorry — skimmer-for-linux is a native Linux desktop app (C + GTK4). It runs on a Linux PC and takes IQ from a TCI radio over the network. 73 de OK1BR

[Richard Fakenberg (OK1BR) @ok1br]

@aprsfi Really nice work! The Mac UI is gorgeous, and per-word confidence in the tooltip is a lovely touch. What's under the hood: is cw_ctc.onnx your own CTC net, fed waterfall bins? My tiny TCN+CTC on keying timings lost to my Viterbi decoder on a live band. 73 de OK1BR

[Richard Fakenberg (OK1BR) @ok1br]

skimmer-for-linux 0.4.0 — the best feature is one I deleted.

The station list is gone, 190 lines out. The waterfall column took its job: a dot per call on its frequency. Click one, the radio tunes there.

1536 channels decoded at once.

73 de OK1BR
#hamradio #cw #sdr #linux

[Richard Fakenberg (OK1BR) @ok1br]

@gmgauthier1967 The lava lamp assumes the chaos is good. Here it's measured: NIST SP 800-90B min-entropy per sample, and only half of it gets credited — 0.42 bit out of 0.83. And 64 B from getrandom() is always mixed in, so the output can't be weaker than the kernel. 73 de OK1BR

[Richard Fakenberg (OK1BR) @ok1br]

I don't own an ANAN G2. W1IZZ does — he ran my code on his. Twice.

He sent back numbers, not adjectives: PureSignal feedback 151 in a 129–181 window, wattmeter within 2 W of an LP-100A.

sdr-for-linux 0.5.0, G2-tested.

73 de OK1BR
#hamradio #sdr #hpsdr #anan #linux

[Richard Fakenberg (OK1BR) @ok1br]

An RTL-SDR dongle, aimed at empty sky, now makes my passwords.

Useless — /dev/urandom was right there. Fun — every character carries measured entropy, not vibes: NIST SP 800-90B, half thrown away.

radio-noise-key-generator 0.1.0

73 de OK1BR
#hamradio #rtlsdr #sdr #linux

[Richard Fakenberg (OK1BR) @ok1br]

73 RTTY QSOs in SARTG WW RTTY — whole stack my own, three releases today.

• sdr-for-linux 0.4.0: native RTTY, direct FSK 45.45 Bd/170 Hz
• skimmer-for-linux 0.3.0: RTTY decode, 768 ch, 11% CPU
• log-for-linux 0.3.0: macros key the FSK

73 de OK1BR
#hamradio #rtty #sdr

[Richard Fakenberg (OK1BR) @ok1br]

sdr-for-linux 0.3.0 — GPU rendering is now the default, not an experiment.

• Waterfall is a GPU texture, cairo draws only the spectrum strip
• Our own drawing: ~1.1 ms/frame. A busy band scales 1 ms, not 13 ms
• paru -S sdr-for-linux

73 de OK1BR
#hamradio #sdr #amateurradio

[Richard Fakenberg (OK1BR) @ok1br]

The AUR is taking uploads again after June's malicious-package incident — 50 packages in half an hour, against 7 in nine days last week.

My ham radio apps are finally up:

paru -S sdr-for-linux skimmer-for-linux log-for-linux

73 de OK1BR
#archlinux #hamradio #amateurradio #sdr