External radio tracking: can lose sync when rapidly changing frequencies

[thedillybar]

SDRC v3.3

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

Radio is Icom 756 Pro III with Omni-Rig v1.2.

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.

2024-01-09 08_16_56-Omni-Rig Settings.png (5.09 KiB) Viewed 1894 times

Have also turned the SDR => Radio Mode tracking ON and OFF; no fix.

2024-01-09 08_19_43-External Radio Options.png (11.15 KiB) Viewed 1894 times

[thedillybar]

I turned Omni-Rig debugging on, and see no evidence of these "blocked" frequency changes. Seems they are not being sent from SDRC to Omni-Rig.

[thedillybar]

A little more debugging...this "blocking" happens when ">SDR" is visible in External Radio. It seems SDRC blocks setting the External Radio freq while it is verifying the SDR freq is correct.

Maybe this step is taking longer than it should w/ RTL-SDR which adds to the problem.

2024-01-09 10_13_38-RTL Dongle USB - R820T __ SDR Console v3.3.png (6.85 KiB) Viewed 1870 times

[thedillybar]

I went back to v3.2 where this is not an issue. In v3.2, the ">SDR" only appears when the frequency is changed on the external radio. If the frequency is changed in SDRC, it doesn't appear and thus this bug is only an issue if I:
1) change the frequency on the external radio
2) within a second, change the frequency in SDRC

This is much better than v3.3, where a frequency change in SDRC...followed by another freq change in SDRC causes the external radio to lose tracking/sync.