Tony, K2MO here. Need advice on sound cards and simulators.
As you may have heard, Mike, DL6IAK, developed a low-latency HF path simulator which is said to be suitable for testing ARQ modes such as Pactor, VARA, ARDOP and others.
The test setup requires 2 PC's with cable connections between sound cards. The modems audio must pass through the path simulator before it's sent to the other PC which would require separate I/O's.
I would imagine this could be accomplished by using 2 sound cards on each PC which is the way FreeDV's digital voice modem works. The problem is that the extra sound card may add latency to the path simulators existing delay: that delay would be multiplied by 2 with 2 PCs.
The question is: can the modems audio be sent to the path simulator using some other method of programing magic? I thought of using virtual audio cable, but my guess is that the latency would be much greater than using 2 sound cards.