Audio in Digi-U with more than one virtual receiver

[Juergen Sturhahn]

Hello,

after the successful setup of a Hermes Lite II as separate RX for my old
Yaesu FT1000 I experienced a strange audio problem.

Setup:

SparkSDR mit 4 virtual reiceivers: 14.074 Digi-U, 21.047 FT8, 24.915
Digi-U and 28.074 FT8

Audio Input: Line 1 Virtual Cable (VAC), Audio Output: None

Rigctl: not enabled, filters set to 10 Hz (low) and 3400 Hz (high), AGC
on, Drive 0 (settings for all receivers identical except FT8 and not
Digi-U on 21.074

WSJT-X Radio is DXLab Suite Commander, DXLab Commander controls PTT and
frequency of the FT1000

WSJT-X Audio: Input by Line 1 Virtual Cable (VAC), Output by separate
soundcard as audio input for the FT1000

When I changed the frequency in one receiver, e.g. 14.074 Digi-U, by
manual setting of the figures to 24.915 and changed the frequency in
WSJT-X accordingly I realized (later) that the audio input to WSJT-X did
not change. In SparkSDR, however, the correct audio belonging to the new
band (24.915) was displayed and the signals decoded properly (after
switching from Digi-U to FT8, later on switching back to Digi-U again).

I have found this when I had not success at all in having a qso with 3D2
even after trying it with high power. It was clear that at this time of
the day 3D2 on 12m would be very unlikely and then I moved back to 20 m
watching the waterfall in WSJT-X and the decoded signals. There was no
change compared to 12m. I then worked 3D2 after two calls.

I removed 3 of the 4 receivers and changed the frequency in the only
open virtual receiver only instead of switching the receivers. The audio
changed according to the new band, everything works as expected.

73

Juergen, DL8LE

P.S.: The terrible performance of the FT1000 RX portion for FTx (even
after switching off the Inrad-Filters and having 6 khz bandwiths in the
2nd IF) is now fully compensated by the HL II. The only additional
hardware is an MFJ switch with RF sensing. The TX portion of the FT1000
allows me to run any power between 10 and clean 100 W.

[ahop...@googlemail.com]

Hi Juergen,

I'm not sure I fully understand, did you have more than one virtual receiver connected to the same vac line? 

73 Alan M0NNB

[Juergen, DL8LE]

Hi Alan,

I am using the same audio settings for all virtual transceivers, i.e. the same VAC line

[ahop...@googlemail.com]

Hi,

that would explain many things, the vac line is like a physical audio lead so the audio from all the virtual receivers will be mixed together( at best) if you send them to the same vac line.  If you want to run many copies of wsjtx you need many vac lines or if you just want one copy you need to get the cat control to work and run a single virtual receiver.

73 Alan M0NNB