Studer 089 channels 1-5 without power

[bluespills]

Hello, I just picked up  a Studer 089 mk ii mixer .  The first five channels don't get any power, but all other channels and everything else are working perfectly. 

Anybody who's familiar with these mixers have any tips where to check first?

Cheers

 

[Joechris]

In my modules there is a fuse in each one. Did you check them? You should change out the tantalums with electrolyt caps in the
power section of every module. They can short the power.
J

 

[PRR]

I don't know Studer. If the houses on my street had power, except the first 5, I would walk from 5 to 6 looking for a tree down through the wires. You don't have trees in there, but something else may be disconnected or just broke, and possibly in the 5-6 gap.

 

[pucho812]

start with the connector for the module and then move onto the module. Can you measure VDC at the connector?

 

[zamproject]

Hi

As the upper audio bus board pcb come within 8 modules, I don't see any reason to have no power for only 5...
My guess is that the lower ribbon signalling bus is not connected or cut between connection input modules 6 and 5 (supply come from right hand facing the console)
Audio may partially pass without, but locked to mic input, as input select is done via relay which take power at signalling bus.
Also mute led won't lit.

If you don't see a ribbon between connection modules 5 and 6 check you don't exchange with connection  module 1, which don't carry the ribbon to connect to next one as it's the last in the chain...

Best
Zam