Icom HF: Communication fails between programmer and radio

Modified on Tue, Sep 9 at 2:31 PM

Communication failures between the radio and the Programmer are most often caused by combinations of settings on the radio. Some of the decisions and adjustments needed are driven by the port in use on the radio (i.e., the CI-V port or the USB port). The points given here affect all Icom radios with a CI-V port and a USB-Port that can be used for CAT operations.

First and foremost, be sure the cable is plugged into the correct jack on the back of the radio. Check your User Manual for the radio to be sure. Most times the CI-V port is the same size and shape as the external speaker jack. You will not get data transfer through the speaker jack.

While not all settings are critical, it is critical that the settings on the radio match that of the Programmer. To check or set values in the Programmer, go to Communications | Set Radio ID

On the radio:

Select Menu
Set
Connectors
CI-V
Set CI-V Baud rate to AUTO. This works well and solves many other issues that could arise from other settings.
CI-V Address should not have to change. Make a note of the CI-V address and check that value in the Programmer matches what was seen on the radio. These MUST match or this process will fail.
CI-V Transceive - Off or On will work, however, if On and you turn a knob or press a button once the data transfer begins, the information emitted by the radio could interfere with the data stream from the radio. Off is a better bet. Note: We have seen times that this option needs to be toggled to get everything flowing. Not that Off or On matters, but the toggle seems to get data flowing between the radio and the computer again.
CI-V Remote Transceive Address - No change here. This option is for a function other than computer programming.
CI-V Output (for ANT) - Set to OFF.
CI-V USB Port:
Link to [Remote]
1. Joins the USB port and the Remote Port essentially eliminating one of the two ports on the back of the radio.
2. Limits Baud rate to 19200 (as controlled by the first CI-V Baud Rate setting).
Unlink from [Remote]
1. Lets the Remote Port and the USB ports on the back of the radio function independently.
2. Allows baud rates up to 115200
CI-V USB Baud Rate - Auto is best.
CI-V Echo Back - Off or On. The Programmer handles it either way.

But if Cannot Find Valid Baud Rate persists

The USB port on the back of the radio into which the USB-B end of a USB-A to USB-B cable connects is multi-functional. Through USB Serial Function in the menu of the radio, set the function for that port:

CI-V - If you are controlling or programming the radio from the computer or doing other CAT functions.
RTTY Decode - for RTTY operations. If set here, the Programmer will fail with a No Valid Baud Rate error.

09/09/2025 12:14PM