Behringer Phantom Power, NOT working

[Delta_Slider]

I bought a Behringer Eurorack MX802A used. Everything on it seems to work fine except the phantom power, I switch it on, the LED goes on and then fades and goes out. I have another pre-amp so I know its not the cables or the mic, etc.

I have been told a couple times that Behringer had trouble with the power supplies and that is the problem. Seems odd to me since the rest of the board works. Will a new power supply fix the problem?

Thanks,

 

[TheDewd]

It's probably the 48V generator that is shut...most likely a capacitor that holds some charge. You could probably fix it yourself, providing you have a nice knowledge of electric circuits.

The 48V is probably generated by:

1) A DC charge pump

or

2) A separate switching supply

Either circuit is quite simply and can be easily fixed.
If the remaining of the board works well, the main power supply is surely good.

 

[Delta_Slider]

Thanks for the info, I'll think twice before just ordering a new power supply. However, I am not too handy with electronics so I guess I will weigh the costs of having it fixed vs buying a new one.

 

[TheDewd]

Thanks for the info, I'll think twice before just ordering a new power supply. However, I am not too handy with electronics so I guess I will weigh the costs of having it fixed vs buying a new one.

As I said, the problem lies WITHIN the mixer, not with the external power supply. So changing it will NOT improve matters. You have to open the mixer up and perform the repair.

 

[travelin travis]

you can get the schematic here: http://www.eserviceinfo.com/downloadsm/7446/Behringer_MX802.html

if you can't fix it yourself, this would help someone that knows how.

 

[reshp1]

I had one like that, it was the switch itself on mine. Try flicking yours on with varying force, I bet there's a sweet spot where it'll turn on. Anyway, just break out the two wires going to the switch and wire them up to a replacement switch.

 

[Delta_Slider]

It WAS the switch! WooHoo! So for now I have it bypassed and if the main is on then the Phantom is on. Anybody see any reason why I couldn't leave it this way? I almost always need to use the phantom power anyway.