weechat-radio:$ Weak signals

Presets

Each preset is a sound speed. On HF, go slower only when the faster one keeps failing.

Switch with /radio preset <name> or /preset <name> in the window. First mode is what the status bar TX field shows on the first key-up. A missed ACK steps down that list and stops at the last one.

The receiver hears all of these at once. You can send hf-weak while they are still set to hf-poor.

What the program does for you

1. If nobody ACKs your message, it sends it again (three tries by default).
2. Each retry uses a slower, tougher waveform. The status bar TX field shows the current one (for example RDM-300S).
3. RETRY counts how many extra sends have gone out.
4. When an ACK comes back, it includes how strong they heard you. A good report steps the waveform back up.
5. Lines that start with !! (emergency) go out twice, a moment apart, so a fade is less likely to take both.
6. Group chat on HF is split into pieces. Any two of three pieces rebuild the message. If several internet gateways each hear a different piece, the hub stitches them.
7. If the frequency is already busy, the program waits for a gap (status bar PTT reads wait). A station’s first three beacons go about a minute apart, then one every 5 minutes. A due beacon waits until an exchange in progress is over (a line and its receipt, a mail and its acceptance), for one exchange at most, and goes ahead of this station’s own queued lines. High occupancy holds it only while frames are being decoded. The countdown shows that time: after exchange, pending until the beacon reaches the modem, and busy while a decoded frame is still fresh. Lines sent in the first rf.startup_hold_s seconds after start (120) wait until another station has been heard (not on VOX, which sends no beacons). Group ACKs and retries are staggered so they do not all key at once. #bulletin stops at [ok]. When the retries are used up the line waits two more intervals, then shows [no].

Busy channel

modem73 carrier-sense is on for every preset. On top of that, wcr keeps a single air queue: one frame (or fragment burst) at a time, emergency first, then ACKs, then your chat, then relays, then beacons.

OCC in the station panel is channel occupancy 0–100. wait means a frame is queued until the channel is idle. After the defer cap it is handed to the modem anyway: 3 seconds for an emergency or an ACK, 15 seconds for chat and relays. An ACK is then keyed with the modem's carrier sense off. Chat and relays can still be held by a carrier the modem hears.

Steps (HF fading)

1. Check audio first

   Confirm audio is good, not low or hot. Distortion is worse than a weak but clean signal.

2. Start on hf-poor

   Set a starting preset:

   /radio preset hf-poor

3. Test one line

   Send a short test to a station you can already hear, or to #bulletin.

4. Let it step down

   Watch the status bar. If RETRY climbs, TX steps down the list in the table above (on hf-poor that is RDM-600S → RDM-300S → MFSK-32R). Leave it.

5. Go slower by hand

   If nothing decodes after several tries, set hf-weak yourself, then hf-deep for a one-line check.

Knobs in wcr.toml

[rf]
max_retries = 3       # extra sends. [x4] is the last copy, then two waits before [no]
frag_k = 2            # pieces of data
frag_m = 1            # spare pieces; any 2 of 3 rebuild the message
emergency_dup_ms = 400
csma = true
slot_ms = 100
quiet_ms = 300
max_defer_ms = 15000
emergency_max_defer_ms = 3000
turnaround_ms = 250
congested_pct = 60
ack_dither_ms = 800
beacon_jitter_s = 15
retry_jitter = true   # routine waits 45s, 90s, 180s, then 360s twice before [no], each × 0.75–1.25
startup_hold_s = 120  # own lines wait until another station is heard. 0 sends at once. None on VOX
outbound_max_age_secs = 3600  # older unacked outbound is [no], including after restart