Stuck in standby mode

[jmillerdoc]

Hello everyone!
I have a Parasound DR40 stereo digital receiver. It powers on fine and tunes FM stations very easy but has no sound due to staying in the "stand-by mode"

Question....is this an easy fix? Where do you start with this sort of problem. It's not like you just pop the cover and start looking for a burnt transistor or something. Any help at all will be greatly appreciated!

Thanks to all!
Sincerely,
Jeff Miller

 

[Iain McNeill]

Most likely is it's failing a power on test and so the logic won't turn on the outputs for fear of destroying the speakers.

It'll be hard to fix without schematics.

You could glean a little more information by trying to find the output relays (if in fact it uses relays - I'm only guessing here) and determine which are the amplifier outputs and which are the speaker terminals (should get 0ohms from speaker terminals to these pins on relays.)

Once you know where the amplifier outputs are on the relays you can power up and see if there's anything on these pins. If they're pegged to a voltage rail or have significant DC offset (more than a volt) then the amp has gone south. On the other hand, If you can see a valid signal on a scope then maybe the output protection logic is bad?

With any luck there's someone on the forum who knows more than me

 

[ham1]

Jeff,

I wonder if you ever got your DR40 receiver repaired? I have one with the same problem. I thought if you found what was wrong it might same me some time troubleshooting it. It is not switching the relay. I checked the output transistors and related drivers, check OK. I have been requesting a schematic but no luck. Probably missing a voltage or relay driver transistor is bad.

Thanks,
Chris

 

[jmillerdoc]

I did not, tore it apart for salvage parts.
Jeff