Ultimation VCA Group Solo/Cut weirdness

[BLZProductions]

Hi

I was out at a client's yesterday trying to get their Ultimation working.
Initial problem was missing 5V on the Analogue supply to the Fader busboards.
Turned out to be a blown fuse on the Ultimation power distribution board caused by the Zener going almost short.
Got that up and running and everything looked OK. Motors and VCA modes looking OK.

However...
Noticed about 8 channels were not responding to SOLO/CUTs from the VCA groups (All working find from channel SOLO/CUTs)
Put the channel on an extender... and the fault goes away. In the desk fault... out of desk no fault.
Managed to pin the issue down to the logic card, but then ran out of time.

Any thoughts on what's going on?

[horizonsound]

Been through this trauma before.

Most of the issues were because of the E03 multiplexer card. IC T23 (4016) and IC T24 (TL084).
In addition, on the E354 VCA card, IC 11 (4081) and IC 9 (4001).

The cut signal goes through these components. If I recall, the VCA group cuts are generated within the computer. They are then sent back down the channel's data lines, and via these cards and ICs.

Anthony.

[BLZProductions]

Ah great.

Thanks for the pointers.
I kinda ran out of time trying to trace the signal.
Going back on Tues to have another look.

Now I'm better armed.

Thanks