Connection
Connect rear USB Type-B to PC with a data cable. Install KENWOOD’s virtual COM driver; identify its COM and USB Audio. PSRTTY uses USB audio directly; no ARUA-10 audio bridge is needed.
Radio settings · AFSK
Start on MAIN LSB-D1. Hold DATA/SEL to open Modulation Source; select Data Mode1. D1/D2/D3 are separate; USB-D1 and LSB-D1 share D1 settings.
| Item | Setting / check |
|---|---|
| Mode / MAIN | LSB-D1 |
| Modulation Source → Data Mode 1 → SEND/PTT | In Data Mode1, USB Audio=On; MIC/ACC2/OPTICAL=Off. Set SEND/PTT too for PSRTTY CAT PTT with USB audio. |
| Modulation Source → Data Mode 1 → DATA SEND(PF) | Data Mode1 DATA SEND(PF): check USB Audio=On. This data-send USB source is On by default. |
| 7-05 USB: Audio Input Level | Keep working FT8 gain; adjust with Windows/PSRTTY TX volume, starting low while watching power/ALC. |
| 7-08 USB: Audio Output Level (Main Band) | Keep FT8 value; check Windows/PSRTTY RX level. |
| 7-01 Baud Rate (USB Port) | Match PSRTTY baud; start with the working FT8 rate. |
| 6-08 SSB-DATA Filter / HI-LO | Pass both2085/2295Hz tones using HI/LO or WIDTH/SHIFT. Use radio controls if DATA bandwidth cannot be changed from PSRTTY. |
| 7-14 Audio Output Type | Received Audio Only — Output received audio only, without beeps/sidetones. |
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.
According to the manufacturer manual, FSK enters ACC2 pin 2 (RTTY). A USB cable alone cannot key FSK on this model. Use DTR/RTS on a dedicated COM through a compatible FSK interface. Never wire RS-232 levels directly to the radio input.
Radio settings
| Radio item / connection | Setting / matching |
|---|---|
| Operating mode | PSRTTY RTTY / RTTY-R corresponds to FSK / FSK-R on the radio, not SSB LSB-DATA / USB-DATA. |
| PTT (TX/RX switching) | Set PSRTTY PTT to CAT |
| FSK input / keying | ACC2: 2 RTTY / 4 GND |
| Serial connection | Use a separate FSK COM port from CAT for this model. Check the connection and avoid PTT signal conflicts. |
| ACC2 PTT | 13 SS / 12 GND |
| 2-06 FSK Spacing | 170 Hz |
| 2-07 FSK Keying Polarity | Off / On |
| 2-08 FSK Tone Frequency | 2125 Hz |
| Audio IN | Use the usual receive audio input |
With external control set to radio PTT, a dedicated FSK COM can share different lines, for example FSK=DTR and PTT=RTS. Keep this port separate from CAT and never assign both functions to one line.
Keying polarity mapping
| PSRTTY inversion | DTR OFF | DTR ON |
|---|---|---|
| Not inverted | Mark | Space |
| Inverted | Space | Mark |
On ACC2, polarity Off means grounding pin 2 sends Mark; On means Space. Interface inversion can change the relation to PSRTTY DTR/RTS ON/OFF. Check radio polarity and PSRTTY inversion using an RY test.
Manufacturer reference: manual / USB port settings (TS-990S)
If FT8 already works
FT8 USB-DATA and PSRTTY LSB-DATA share input/gain when using the same DATA configuration. Keep devices/gain first; verify LSB after connection. Plain USB FT8 needs separate DATA-source checks. If FT8 uses D2/D3, distinguish that configuration from D1. Verify MAIN RX reaches the PC without unwanted SUB audio.
PSRTTY settings · AFSK
Select TS-990S,Hamlib,CAT PTT. Specify USB virtual COM,baud and this radio’s Audio IN/OUT. Close FT8 and test connection. Start connection mode LSB-D1; check actual display/audio source.
No modulation
CAT TX without RF: DATA mode→USB source for the TX method→Audio OUT→USB input level/PSRTTY volume. MissingRX:Audio IN,USB output level,RX filter.
Official sources
- TS-990S USB Audio Setting Manual
- TS-990S Instruction Manual
- KENWOOD FT8 / DATA source FAQ
- KENWOOD USB Audio / ARUA-10 notes
Based on official manufacturer operating/CAT manuals. Names and positions may vary by firmware/region.