On our Qu-32, the 5vdc rail on either fader board of ours drops to 4.5vdc any time there is a fader move, so I had high hopes this would fix our issue.
There were actually five PTC fuses on the board with the master fader, and four on the board that has faders 1-16.
I probed each of them and they rung out at about .5 ohm each, with one coming in at .7 ohm, so maybe we aren’t having the same problem.
In any case, before I went to the trouble of replacing the PTCs, I just bypassed all of them with some thin wire.
Unfortunately, bypassing them didn’t fix our issue.
When I was taking voltage readings from these boards, I noticed they are being fed with 12VDC, so the buck converters to get it down to 5vdc must be on each board.
The 12vdc feeds did not drop in voltage with a fader move, so I figure some component of the buck converters has deteriorated.
There are several electrolytic caps on these boards, some near the 12vdc feeds, so these may be the issue. None are discolored or swollen.
