VCA group number 4 distorting >>>SOLVED<<<

[oyanliz]

Hi all,

The VCA group 4 stopped working correctly today. When thumbwheel is selected for sending to VCA 4 from any channel from any bucket... VCA 4 fader is bypassed and sounds distorted. We have replaced the VCA fader but the problem is still there. The console has the computer jumpers installed. I have been checking all the ICs from the CF82E20 card (all ICs are new and working fine), T13 and T24 transistors have been replaced...

I get stuck, I do not know what can I check next.

I would apreciate any help.

Thanks in advance.

Best regards.

Oihan

[oyanliz]

Hi all,

The problem is in the card, as we replaced it with a spare card and it works fine. We found a bad resistor in the original card (have been changed) and replaced the ICīs (they were new but...).

Seems that all the diodes are working fine.

Any idea would be welcome.

Regards.

Oihan

[oyanliz]

Hi,

All diodes looked working fine on the card, but we decided to replace D4 and D12 diodes, just in case, for ensuring the correct flowe of 4th VCA signal. After changed those diodes... the problem have been solved.

Regards to all!!

[Dan Korneff]

Running into the same issue here. Any channel set to VCA 0 overloads. I replaced some transistors that were blown up on the CF82E20, which fixed some unknown problem, but not this one. I'll report back when I track down the cause. Maybe it's diodes here too

[Dan Korneff]

For me, it ended up being T18 and T30. All is good over here