ijor wrote:In this case the bands are more clear, those are not just glitches. I believe however that the cause is very different on the IMP Shifter than on the -38 (or -20) one. It would be interesting to see if adding the diode at the VCC pin fixes the problem. I suspect it might.
Sorry, it doesn't. So, (given that my TT is sadly down for repair) today I had some time to play with my IMP STfm. I confirmed that by default there is no diode between +5V and the Shifter's Vcc pin -- I measure 5 V on the IMP Shifter. Then I added the diode, dropping the Vcc of the IMP Shifter to approx. 4.4 V. However the artifacts in "Let's Do The Twist Again" are still present. Also, I retested the SNDH Update Demo, where I had previously noticed artifacts with the IMP Shifter. They are still present as well at 4.4 V.
Anything else you want to have tested?
I will repeat the test with the -20 Shifter now. And after that, maybe already tomorrow, I can do the measurements on the IMP Shifter (without diode) you asked for.