api 525 weirdness

[pucho812]

4X 525 comps, all missing doa's. Put in doa's for all of them.  They all exhibit the same Behavior.  The moment they are plugged into a api rack. the needed bounce like a clock, showing compression as if hit by a quick transient then returning to non compressed then doing it again. It's like on, off, on and I would say it's ticking once a second.    This goes on for as long as there is power being supplied. I have yet to hear if there is any audio present or anything as the moment they did that, I just shut off the power and have no extender cards.

Also the controls seem unresponsive and it will do this regardless of how they are adjusted.

 

[Andy Peters]

4X 525 comps, all missing doa's. Put in doa's for all of them.  They all exhibit the same Behavior.  The moment they are plugged into a api rack. the needed bounce like a clock, showing compression as if hit by a quick transient then returning to non compressed then doing it again. It's like on, off, on and I would say it's ticking once a second.    This goes on for as long as there is power being supplied. I have yet to hear if there is any audio present or anything as the moment they did that, I just shut off the power and have no extender cards.

Also the controls seem unresponsive and it will do this regardless of how they are adjusted.

sounds like power-supply overload/foldback. How much current does each module draw?

-a

 

[pucho812]

Hmmm interesting except it's an 11 space rack and only had the 4 525 modules in it at the time. Current draw per module? I honestly don't know off hand. I doubt the 3 doa's that got put in are drawing over the limit per module.

Maybe I should put in 2520's vs these other doa's I was asked to put in.

 

[Biasrocks]

Vintage 525's need to have some traces cut and re-routed in order to work in a lunchbox.

You'll see that Pin 6 (Low Input) is routed to Lamp Power on the new pin-out, that could definitely
give the compressor fits.

 

[pucho812]

Vintage 525's need to have some traces cut and re-routed in order to work in a lunchbox.

You'll see that Pin 6 (Low Input) is routed to Lamp Power on the new pin-out, that could definitely
give the compressor fits.

Oh right right. That totally might be the cause. I know I didn't redo the traces and I doubt that has been done.

edit: yes traces been rewired. I think I just put in some funky(possible faulty) doa's.

 

[hereforever]

Wondering if/how you resolved this?

I have a vintage module that is exhibiting similar behavior.  Works fine with compression turned off, but once turned on the meter pins, I get distorted noise and the audio cuts off completely correlating every time the meter spikes.