Connection
Connect the PC to the controller’s rear USB B (Type-B) using a data cable. USB carries CI-V and TX/RX audio; no separate audio interface is needed. This differs from the RF DECK / CONTROLLER connection to the RF deck. Install the official driver and select IC-7760 Serial Port A (CI-V).
Radio settings · AFSK
MENU → SET → Connectors. TX: MOD Input; RX: USB AF/IF Output. DATA1 MOD, DATA2 MOD and DATA3 MOD choose separate inputs: check D1/D2/D3 on the mode display. USB audio input differs from USB sideband.
| Item | Setting / check |
|---|---|
| Mode | Start with LSB-D: SSB Data, not the radio’s native RTTY mode. |
| MOD Input → DATA1 MOD | Check DATA1 MOD = USB. Factory default is USB; check for earlier changes. DATA2 defaults to LINE-IN, DATA3 to ACC. PSRTTY 1.16 auto-switches Data to D1. |
| MOD Input → USB MOD Level | Keep the working FT8 value first. Factory default: 50%. Adjust with PSRTTY TX volume. |
| USB AF/IF Output → Output Select | AF: sends received audio to the PC. |
| USB AF/IF Output → AF SQL | OFF (OPEN): prevents radio squelch from cutting PC audio. |
| USB AF/IF Output → AF Output Level | Keep the working FT8 value and check PSRTTY RX level. |
| CI-V → CI-V Address | Default B2h. Match PSRTTY to the radio’s actual CI-V address. |
| USB (B) Function | No change needed for Port A. Select CI-V only when also using Port B for CAT. The default RTTY/PSK Decode outputs the radio’s decoded text; it is not CAT control. |
FSK keying transmission · Ver1.18
Example: DTR for FSK and CI-V/CAT for PTT. Adjust settings to your wiring and selected signals.
Serial keying for TX; Audio IN for RX. Neither primary nor secondary Audio OUT is used. Check radio RTTY mode, 170 Hz shift and Mark frequency. Keying polarity is independent of RX inversion.
Connect the radio to the PC with one USB cable to use FSK. See FSK keying output for the radio settings.
Radio settings
| Radio item / connection | Setting / matching |
|---|---|
| USB Keying (RTTY) | USB (A) DTR / USB (B) DTR |
| USB Keying (CW) | OFF |
| USB SEND | OFF |
| Operating mode | RTTY / RTTY-R |
| RTTY shift | 170 Hz |
| RTTY Mark frequency | 2125 Hz |
For radios with A/B ports
| Shared CI-V port | USB Keying (RTTY) |
|---|---|
| A | USB (A) DTR |
| B | USB (B) DTR |
A/B identifies a port; DTR/RTS identifies its line. When sharing CI-V, select the same A/B side for USB Keying (RTTY). CI-V on B depends on the model/port-function setting. The original IC-7300 has no A/B choice: select DTR/RTS only.
Keying polarity mapping
| PSRTTY inversion | DTR OFF | DTR ON |
|---|---|---|
| Not inverted | Mark | Space |
| Inverted | Space | Mark |
This table maps PSRTTY control signals. It is independent of A/B selection and RX decoding inversion. Start without inversion, then match the radio/interface polarity.
Manufacturer reference: manual / USB port settings (IC-7760)
If FT8 already works
Even with FT8 in USB-D, check DATA1/2/3. USB-D and LSB-D share input only for the same Data number. FT8 DATA2 may already use USB, but PSRTTY 1.16 auto-switches to DATA1, so DATA1 MOD must be USB. Plain USB uses DATA OFF MOD. Keep the working FT8 USB MOD Level first.
PSRTTY settings · AFSK
Select IC-7760 and CI-V CAT PTT. Explicitly select its USB CI-V COM and the same IC-7760 USB audio device for Audio IN/OUT. Start with LSB-D. Close other apps using that COM.
No modulation
Compare FT8 and PSRTTY output devices → verify LSB-D after connection → check DATA1 MOD = USB → check USB MOD Level and PC/PSRTTY transmit volume. Start with low audio and observe radio power and ALC.
Official sources
Based on official IC-7760 documentation. Menu names/positions may vary with firmware or language.