It was a dark and stormy night.
Although not strictly recording and guitars I thought the sleuths here may have some ideas...
I have a curious case of wandering output power on a radio transmitter set up.
This is a digital radio system that uses the sound card to decode and generate the digital tones. The output audio level translates directly to transmitted output power, i.e. if you turn up the volume the transmitter power increases, decrease the volume power decreases.
A little while back I upgraded the laptop I use to run the software to Windows 10.
The upgrade from Windows 8.0 was long overdue and was prompted by several apps I use no longer offering support on Windows 8.
The upgrade was not without issues but after a few hours farnarkling about a workable platform was in place.
So off to the shack and onto the airwaves.
Over the last few weeks I have noticed that I have to keep an eye on both my output power and ALC meters while the system is transmitting. The output power wanders, sometimes up and sometimes down without any knowing changes from me.
An adjustment of the output power slider in the software (WSJT-X if anyone is interested) and all settles for a while.
I suspect that the Win10 audio driver and built in audio card may be causing the wander. Prior to the OS upgrade the driver had both the windows driver and an OEM driver for the sound card, there is no Win10 OEM driver available, so the Windows driver is the one in use. It recognises the card and seems to (otherwise) operate correctly.
I am awaiting an el cheapo external USB sound card, well a $20 one - not the $4 one. The thought is to move the audio I/O that the software is using onto the external card to eliminate the Win10 driver and internal card from the set up.
(A thought occurred while typing this - why wait for the external card? Why not use the USB mixer I have sitting idle in the other room? Tomorrow may see that experiment).
Has anyone come across this audio level wander before?
I can understand the output audio (and therefore power) changing slightly as the output frequency is moved up or down the spectrum this being a function of the generated tones vs the frequency response of the sound card but the wandering happens without any such change.