I would use psk like interfaces. Of course a block capacitor, an audio 1:1 600ohm transformer, a fixed attenuator plus a volume potentiometer between the ubitx mic input and the output of the sound card. And interface like that may be used for SSB as well, other than digital modes of course. 'Voice Shaper' is a very good free Windows program that would add a 'virtual compressor' to the Ubitx. I had tried Voice Shaper 10 years ago, when I was still using Windows, and I was impressed.
Il 03/mar/2019 19:46, "Evan Hand" <
elhandjr@...> ha scritto:
In addition to the capacitor that Robert is suggesting, be sure to try the level adjustment on the PC.? I found that I had to run at very low volume levels when doing my two tone tests using the PC as the tone generator.?
The second thing is to verify the type of jack on the USB sound card:? Is it a TRRS (Tip Ring Ring Sleeve) like stereo headphones with mic, or just the one ring.? The wiring on the TRRS version puts the ground on the ring closest to the sleeve, and the sleeve is the mic input to the PC.? For me I had to get a TRRS plug to get it wired correctly.? Tip and First Ring wired together to the mic input on the uBitx with ground to the second ring of the PC plug and Sleeve on the uBitx.? No connection to the sleeve on the PC side of the cable.
Lastly, you may need to add a level control potentiometer, though I did not.? I would put a DC blocking cap between the uBitx and the level control wiper, do not believe you need one on the output of the sound card.
these are my thoughts, you might want to get some more input before implementing them.
73
Evan
AC9TU
