Trident Series 24 Phantom Power Problem

[The Federation]

Hello everyone,
I have a Trident Series 24 console, I recently had the master section and power supply recapped and it did wonders for the console, but mid last week my phantom power stopped working for no obvious reason.
I have done all the necessary checks, such as the connection from the PSU to the console, phantom power fuse, and different mic inputs, but have made head-way as to isolating the problem.

I was wondering if anyone had a similar problem with this console, or similar, and where they started to trouble shoot the problem before I have to bring the tech out here.

Thanks

Michael

[David Kulka]

The best way to narrow this down is with voltage checks. Disconnect the PSU from the desk and check for +48 at the supply connector. If it's not there or has poor regulation, obviously you need look no further.

If you do see +48 at the PSU, connect the console and check again, at the PSU. If the voltage decreases and/or has noise, either the power supply is faulty (likely) or something is drawing excess current (less likely). In the latter case you might test the PSU with a dummy load (say a 200 ohm power resistor) to see whether it stands up under load.

If you measure +48 at the PSU with the console connected but still have nothing at the mic lines, you need to check the PSU cable and the wiring in the mainframe. Maybe a wire has come loose, a fuse has blown, or a motherboard foil has burned.

There are other possibilities, but I think this covers most of the likely suspects. Good luck!

[The Federation]

David,

Thank you for the information. I am going to decommission the console this week and get to the bottom of this. I will post my findings soon as I see what is wrong with it.

Thanks again
Michael