Thetis v.2.5.3 (Beta)
Posted: Sat Jul 15, 2017 7:05 pm
I had a chance to run Thetis v2.5.3 (Beta) for about 6 hours yesterday with my 200D using Protocol 2 firmware v1.1 for the Orion board. For the most part I ran it with a sampling rate of 192k and it behaved very well for the whole session. The Pre-EQ, CFC, and Post EQ all appear to be working fine in this version and so I made 10 transmit profiles to cover my SSB and AM voice sessions.
The first thing I noticed was the addition of the "Port Audio" setting field in the VAC setup form. My VAC audio chain in OpenHPSDR works very well, however, a couple of times an hour it has a tendency to randomly sputter slightly. Some people don't even hear it but Scott (WU2O) and several others can definitely spot it. Unfortunately, buffer tweaking with the existing adjustments has no effect on this particular artifact. What I noticed yesterday while running Thetis was that I did not experience a single instance of sputtering during my 6 hours of operation. Thankfully, the combination of "Port Audio" and "Ring Buffer" adjustments seems to be the elusive solution to taming that problem. I started out with the maximum setting of "240" in both fields and stepped down to as low as 30 in both fields. No sign of any blips, pops, or sputtering. For most of the session I ran with both fields at "240" and figured that I would figure out the lowest setting my system would tolerate in a future session.
At any rate, thanks for the addition of the "Port Audio" adjustment!
I tuned around with sampling rates of 384k, 768k, and 1536k and found when switching between them that after a few soft pops and clicks in the receive audio they settled down and worked very well. I stayed with 192k whenever I was in a QSO and that worked fine. I did some "dummy load" testing with Pure Signal and it did auto-attenuate appropriately and the feedback and correction indicators confirmed it was operating. The panadapter display of the transmitted signal with Pure Signal looked a bit strange so I was suspicious about what the signal actually looked like but while monitoring with my RSP SDR receiver it looked to be cleaner with PS running than without. I didn't have the RSP SDR coupled to the second port of the RF sampler so I could not really determine how much correction was going on. I'll get a better look next time.
Thetis is starting to look very promising!
73,
Rob W1AEX
The first thing I noticed was the addition of the "Port Audio" setting field in the VAC setup form. My VAC audio chain in OpenHPSDR works very well, however, a couple of times an hour it has a tendency to randomly sputter slightly. Some people don't even hear it but Scott (WU2O) and several others can definitely spot it. Unfortunately, buffer tweaking with the existing adjustments has no effect on this particular artifact. What I noticed yesterday while running Thetis was that I did not experience a single instance of sputtering during my 6 hours of operation. Thankfully, the combination of "Port Audio" and "Ring Buffer" adjustments seems to be the elusive solution to taming that problem. I started out with the maximum setting of "240" in both fields and stepped down to as low as 30 in both fields. No sign of any blips, pops, or sputtering. For most of the session I ran with both fields at "240" and figured that I would figure out the lowest setting my system would tolerate in a future session.
At any rate, thanks for the addition of the "Port Audio" adjustment!
I tuned around with sampling rates of 384k, 768k, and 1536k and found when switching between them that after a few soft pops and clicks in the receive audio they settled down and worked very well. I stayed with 192k whenever I was in a QSO and that worked fine. I did some "dummy load" testing with Pure Signal and it did auto-attenuate appropriately and the feedback and correction indicators confirmed it was operating. The panadapter display of the transmitted signal with Pure Signal looked a bit strange so I was suspicious about what the signal actually looked like but while monitoring with my RSP SDR receiver it looked to be cleaner with PS running than without. I didn't have the RSP SDR coupled to the second port of the RF sampler so I could not really determine how much correction was going on. I'll get a better look next time.
Thetis is starting to look very promising!
73,
Rob W1AEX