Pioneer PDR-05 no sound

[Beacon64]

Hi
I recently bought a PDR-05. It's a nice bit of kit but it has a problem - I can't get any sound out of it . The drawer opens, cd spins, TOC is read and CD plays, and that's it. I've checked analogue and digital outs - nada.

I've looked over the main audio i/o board and checked the Voltage regs - juice is OK. I inserted a blank CD to see if I could get some life in record mode - again zip.

I have bought the service manual and gone through troubleshooting - but it doesn't cater for this type of trouble!

I'd be grateful for any suggestions or experiences from members who have had similar issues.

All the best
Bernie

[Mooly]

Hard to say... as you have a manual perhaps start at the outputs and work back (or is that forwards ) Look for any muting circuit, see whether it's in the wrong state etc.
Just normal fault finding... even buzzing inputs of any op amps in the analogue stages etc to see if there is any output.

If you can post an image of the circuit analogue side of things might have a better idea what you can check.

[Mooly]

Have just noticed you say no digital output output.
Hmmm... are there any set up menus etc that might be used to mute the output. The fact it "plays" and reads the TOC etc is all to the good.

Really guessing without ever having seen one.

[event horizon]

Originally Posted by Beacon64

I've checked analogue and digital outs - nada.

Bernie

Hi Bernie, if you aren't getting anything on the digital output then i'd assume the problem was something in the digital domain rather than analogue. If the analogue stage had failed then the digital output would still function (unless it was a power supply issue) This appears to be a logical deduction, though i could be a country mile out

Frankly i'm pretty useles to you here as i have only ever dealt with analogue electronics, as that is what has interested me.

You need someone who knows what they are doing with the gubbins i know nothing about, sorry.

Best of luck with it anyway

[Beacon64]

Thanks for the quick responses! I've checked for a mute - there is, however it appears to be a record mute, so really shouldn't have any effect on output.

I note on the input selector between digital 1, digital 2 and analogue, the level display shoots off the scale on analogue but not on digital. My next port of call, I think!

[Beacon64]

After the encouragement, I removed the i/o board and inspected the digital board beneath. I found a slightly corroded component which I didn't recognise immediately. I removed the board and found more gunk, that had leaked out. On removal, the component was found to be made by Elna. It looks like a submin battery but is a super capacitor, 0.22F 5.5V. I've cleaned the board with meths - my favourite tipple - and ordered a new cap. I couldn't source a 0.22F so I've bought a 0.47F 5.5v. I'll report back if this proves successful.

[Beacon64]

Or not, off course!

[Beacon64]

****! Of course! I think I know where I'm going!

[afecu]

Bernie,

Take a look at the thread on the PDR-555RW, which also has an Elna supercap that tends to leak . It's at Please help fixing Pioneer PDR-555RW .

The Elna cap is only used to power the circuit that stores the TOC info before it's written to the CD, in case you lose power, and it's not needed otherwise. On the PDR-555RW, the ATIP decoder chip circuitry is often affected as the traces in the vicinity get corroded, and the unit will not recognize any media . I don't know what's near the Elna cap on the PDR-05, but that would be something to look at further...

I'm also sending you a PM with a little more info.

[Mooly]

It sounds promising as long as the print etc is intact... backup caps and batteries have been a major problem through the years on loads of kit.

You can always put an electroylitic in to test... honest, something like 100uf. It should all work.

Foam cleaner is good for cleaning PCB's with a brush, then wash in warm water... as long as there are no "mechanical" parts, tuned coils etc. Boards come up like new. Done that to dozens of TV chassis too, with no problems.

Good luck