ICOM radios

ICOM satellite rigs use Main for receive and Sub for transmit. OscarWatch talks to the radio over CI-V on a USB serial port.

Supported single-radio models

Model	Notes
IC-910, IC-910D, IC-910H	Same CAT. Set the power class so FT4 uses 20 W, 50 W, or 100 W / 75 W. A saved IC-910 stays on the H ratings.
IC-9700, Japan IC-9700, Japan IC-9700S	Same CAT. Default address 94 (hex A2). Set the power class so FT4 uses 100 W / 75 W, 50 W, or 20 W. A saved IC-9700 stays on 100 W / 75 W. 1200 MHz is 10 W on all three.
IC-9100	HF/VHF/UHF; satellite mode as on other ICOM satellite rigs. Data transponder modes (for example FT4) use USB-D / LSB-D, as on the IC-9700.
IC-821H	Older satellite rig; Main/Sub only (no split CAT). Set uplink CTCSS on the radio manually

Settings → Radio

• Rig type — pick your model.
• IC-910 model: shown when the rig type is IC-910. CI-V cannot tell the 20 W, 50 W, and H sets apart, so choose the 144 MHz rating printed for the radio. A saved IC-910 stays on the H ratings.
• IC-9700 model: shown when the rig type is IC-9700. Choose IC-9700, Japan IC-9700, or Japan IC-9700S from the 144 MHz rating. A saved IC-9700 stays on 100 W / 75 W.
• COM port — the CI-V USB port (check Device Manager on Windows).
• CI-V address — must match the radio (often 94 on IC-9700; IC-910 is often 7A). Wrong address = no CAT.
• Baud rate — match the radio menu (often 19200 on IC-910; IC-9700 USB is often 115200).
• CI-V TRN — should be On on the radio so commands are accepted.

What OscarWatch does on a pass

• Turns satellite mode on for normal cross-band satellites.
• Puts downlink on Main, uplink on Sub.
• On the IC-9700 and IC-9100 (and the IC-705, IC-7300, IC-905, and IC-7100 as dual-radio legs), data transponder modes such as FT4 set USB-D / LSB-D so TX audio comes from USB. Voice modes turn data mode off again.
• Updates both frequencies for Doppler and applies your offsets.
• Keeps you on Main while you turn the dial to hunt SSB — uplink CAT waits briefly so Sub is not selected by accident. See spinning the dial.
• When you quit OscarWatch or disconnect the radio, clears the uplink tone, turns satellite mode off and leaves the radio on Main. This only happens if OscarWatch turned satellite mode on. Untick Turn satellite mode off when OscarWatch closes in Settings → Radio to leave the radio in satellite mode.

Receive-only (ISS SSTV, beacons)

When uplink is 0, OscarWatch turns satellite mode off, puts the downlink on Main, and only tracks receive. See receive-only overview.

Dual radio — IC-705, IC-7300, IC-905, IC-7100, or IC-706 as one leg

IC-705, IC-7300, IC-905, IC-7100, and IC-706 / IC-706MKII / IC-706MKIIG are not full single-rig types in OscarWatch. They appear only when Dual radio is enabled — typically as the uplink or downlink leg paired with another radio (e.g. FT-818 on RX, IC-706 on TX, or IC-7300 on HF downlink for AO-07 Mode A).

Enable dual radio

1. Settings → Radio → Dual radio — tick the box.
2. Set Downlink and Uplink rig types and COM ports (each leg needs its own port).
3. Save and connect — status should show both legs.

IC-705 (one leg)

• CI-V USB Port = Link to [CI-V] in the radio menu.
• Baud — often 115200; match OscarWatch.
• CI-V address — default A4 unless you changed it.

IC-7300 (one leg)

• USB CI-V serial port — match address and baud in the radio CI-V menu.
• Baud — often 115200; match OscarWatch.
• CI-V address — default 94H unless you changed it.
• HF and 6 m only (1.8–54 MHz). Typical for AO-07 Mode A: IC-7300 on downlink (10 m), a 2 m-capable radio on uplink.

IC-905 (one leg)

• USB CI-V serial port — match address and baud in Set mode.
• Baud — often 115200; match OscarWatch.
• CI-V address — default AC unless you changed it.
• Covers VHF/UHF plus SHF (13 cm / 6 cm / 3 cm) for microwave satellite legs.

IC-7100 (one leg)

• Set CI-V Output (USB) On, or use the REMOTE jack.
• Baud — typically 19200 (USB max); match OscarWatch.
• CI-V address — default 88H unless you changed it.
• HF/6 m, 2 m, and 70 cm (AO-07 Mode A downlink on 10 m). 23 cm is not supported.

IC-706 / IC-706MKII / IC-706MKIIG (one leg)

• CI-V via the REMOTE jack (USB adapter).
• Pick the correct leg type in the list — addresses differ: 48H (706), 4CH (MKII), 58H (MKIIG).
• Baud 19200; CI-V TRN On on the radio.
• 706 / MKII: HF/6 m and 2 m (no 70 cm). MKIIG: adds 70 cm. Any 706 variant can use downlink for AO-07 Mode A (10 m) with a 2 m uplink radio.

Common issues

• Radio stuck on Sub. Press Resume tracking if Standby is on, or toggle satellite mode on the radio. See Problems?.
• Uplink lags after tuning: normal until Uplink CAT wait after dial elapses (default 2500 ms in Settings → Radio); uplink then catches up.
• Frequency snaps back when tuning near TCA — short settle period after CAT; try pausing CAT briefly or see Doppler tuning.