When rapidly changing frequencies, sometimes the external radio frequency does not get updated to match the SDR frequency. It usually tracks even when scrolling rapidly, but 5-10% of the time does not. The fix is simply to change frequency again and it updates to match.
Excerpt from external radio log when tracking loses sync. SDRC appears to recognize the frequency change was "BLOCKED" but then fails to retry after the block is cleared.
Code: Select all
08:05:22.441 IC-756 Pro III ParamsChange blocked by timer, params 00000002 = Freq, pending 00000002 = Freq
08:05:22.442 ------------ Frequency = 7199000
08:05:23.327 EXT>SDR blocking clear
08:05:23.327 OutstandingParamsChange, rig 1, params 00000002 = Freq
08:05:23.327 Ext>SDR: SynchroniseCallback (Guard timeout), Frequency 7.199.000, IF output 64452000, Mode 0 (None)
08:05:23.327 Ext>SDR: Status = SDR updated
08:05:23.327 SDR>EXT block set
08:05:23.329 IC-756 Pro III ParamsChange, params 00000002 = Freq
08:05:23.912 SDR>Ext IC-756 Pro III> Frequency 7.199.000, no change
08:05:23.937 SDR>Ext IC-756 Pro III> Frequency 7.173.500, BLOCKED
08:05:24.270 ... (2 more)
08:05:24.270 SDR>Ext IC-756 Pro III> Frequency 7.174.000, BLOCKED
08:05:24.330 SDR>EXT block clear
I've tried changing the Omni-Rig polling rate from 500ms to 100ms and 2000ms; doesn't fix it. 19200 is the highest baud rate available on this radio. Have also turned the SDR => Radio Mode tracking ON and OFF; no fix.