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Contesting

Contest weekends are where QRM piles up fast: dozens of stations packed into a few kHz, overloaded front-ends, exchanges barely above the noise floor. RFWhisper is tuned to preserve decode quality under exactly this condition — never at the cost of busting a call.

Hard requirements for contest use​

  1. Zero decode regressions. If a raw pass decodes K3XYZ and the denoised pass decodes KJXYZ, that's a bug in the model. Run the FT8 regression gate on your chosen model before the contest.
  2. Low latency. No operator wants to hit the TX button two beats behind the other station. Stay under 100 ms p99.
  3. Bypass toggle on one key. You'll want to A/B instantly when a station comes up.
  4. Predictable level. Soft limiter catches overshoots so your AGC / noise blanker upstream stays happy.
Contest typeProfileNotes
SSB phone contest (CQWW SSB, Sweepstakes Phone)ssbFull aggression OK — speech-centric
CW contest (CQWW CW, ARRL DX CW)cwTransient preservation is non-negotiable
RTTY (RTTY Roundup)rtty (v0.3)Careful — don't filter the 170 Hz shift
FT contests (FT Roundup)ft8 / ft4Gentler; let the decoder do its job

Running vs S&P​

  • Running (CQ): keep the denoiser on. You're looking for the faintest caller at the bottom of the pile.
  • S&P: consider running the denoiser for searching, but when you hear a clear station you want to work, the raw signal already has what you need — the denoiser is break-even to mildly positive here.

Sample contest scenario: 40m SSB at 0200 UTC​

A typical late-night 40m SSB contest:

  • Band crowded: 7.150–7.200 wall-to-wall.
  • Your neighbour's inverter adds an S5 rhythmic buzz.
  • You're trying to copy an exchange at S3.
rfwhisper denoise-live \
  --in "USB Audio CODEC" --out "CABLE Input" \
  --model deepfilternet3 --profile ssb \
  --telemetry ./contest-log.jsonl

contest-log.jsonl records rolling SNR gain, RTF, and latency per minute so you can analyze the session later.

Spotting weak multipliers​

Anecdotally: the biggest single-operator benefit is hearing the call sign prefix under splatter from an adjacent strong station. The NN preserves consonant structure that classical NR tends to smear.

What RFWhisper is not​

  • A noise blanker — we don't cancel impulsive transmitter artifacts (keyclicks, splatter). Use your rig's NB for those.
  • A passband filter — use your rig's PBT / DSP bandwidth to set the crop; RFWhisper works inside whatever you hand it.
  • A replacement for a good antenna. +3–6 dB of SNR gain on a compromise antenna is still less than what a real antenna change does.

After-action reports welcome​

Post your contest results with RFWhisper in the Contesting Discussion. Include:

  • Contest + your category
  • Band + mode
  • Model used + profile + hardware
  • Rate improvements / subjective observations
  • Any decodes you're confident the raw audio would not have produced

Your real-world data is how we decide what to improve next.