feat(icom): a DATA button, native PSK, real watts — and the audio codec

The console gains a DATA mode button (USB-D, what FT8 and friends ride on);
the PSK button now maps to the rigs' native PSK mode (0x12) instead of erroring
as an unknown mode — rigs without one NAK it, exactly as RS-BA1's button does
there. The power meter shows real watts on the IC-7760, whose meter face runs
to 250 W where a 100 W rig's percentage was the watts. The clickable S-meter
gets a pointer cursor so it looks like what it is.

Network audio: rxcodec 0x04 — the experiments on the real 7760 settle the
codec table (0x10 = 16-bit stereo, 0x02 = 8-bit mono, both heard as garble),
and 0x04 is the 16-bit mono the playback path actually plays.

internal/cat/civ/civ.go

@@ -131,6 +131,8 @@ const (
 	ModeFM    = 0x05
 	ModeCWR   = 0x07
 	ModeRTTYR = 0x08
+	ModePSK   = 0x12 // native PSK (IC-7610/7760/7851 class; older rigs NAK it)
+	ModePSKR  = 0x13
 )
 
 // Frame builds a complete CI-V frame (preamble … end) for payload, which is the
@@ -306,6 +308,8 @@ func ModeToADIF(m byte, data bool) string {
 		return "CW"
 	case ModeRTTY, ModeRTTYR:
 		return "RTTY"
+	case ModePSK, ModePSKR:
+		return "PSK31"
 	case ModeAM:
 		return "AM"
 	case ModeFM:

internal/cat/icomnet.go

@@ -849,12 +849,12 @@ func icnConnInfo(seq, innerSeq, tokReq uint16, sentid, rcvdid, token uint32, use
 	copy(b[0x60:0x70], icnPasscode(user))
 	b[0x70] = rxEnable // rxenable: 1 opens the 50003 RX audio stream, 0 = CI-V only
 	b[0x71] = 0x00     // txenable (Phase 5)
-	// rxcodec 0x02 = LPCM, ONE channel, 16-bit. 0x10 (two channels) was asked
-	// for at first, and a real IC-7760 duly sent interleaved stereo — which the
-	// 16 kHz mono playback path rendered as garble at double speed. Mono is what
-	// the monitor plays and half the bandwidth; the second channel of an RX
-	// stream carries nothing a logger wants.
-	b[0x72] = 0x02 // rxcodec
+	// rxcodec 0x04 = LPCM, ONE channel, 16-BIT — settled by experiment on a
+	// real IC-7760, one wrong guess at a time: 0x10 produced 1280-byte payloads
+	// of interleaved 16-bit stereo, 0x02 produced 320-byte payloads of 8-bit
+	// mono (samples hugging 0x80). 0x04 sits between them in the codec table
+	// (as in wfview): 16-bit mono, the format the 16 kHz playback path plays.
+	b[0x72] = 0x04 // rxcodec
 	b[0x73] = 0x04 // txcodec
 	icnBE.PutUint32(b[0x74:], 16000)
 	icnBE.PutUint32(b[0x78:], 8000)

internal/cat/icomserial.go

@@ -1494,6 +1494,12 @@ func (b *IcomSerial) modeCode(mode string) (code byte, data bool, err error) {
 		return civ.ModeFM, false, nil
 	case "RTTY", "FSK":
 		return civ.ModeRTTY, false, nil
+	case "PSK":
+		// The console button, not the ADIF mode: the rigs that HAVE a native PSK
+		// mode (7610/7760/7851 class) get it; a 7300 NAKs 0x12 and the button
+		// stays dead there, exactly as RS-BA1's does. Soundcard PSK31 stays on
+		// USB-D below, where every rig can do it.
+		return civ.ModePSK, false, nil
 	case "FT8", "FT4", "PSK31", "MFSK", "JS8", "JT65", "JT9", "OLIVIA", "DATA", "DIGITALVOICE":
 		// Digital data modes ride on USB with the data flag set (FT8 etc.).
 		return civ.ModeUSB, true, nil