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A-12738-50004 WPC Audio Board Help

strongs

strongs

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The audio started to crackle on my Creature From The Black Lagoon the other night and then moments later a couple of tantalum caps on the audio board went POP! C26 and C28 were visually toasted and this also burnt up a trace on the back of the board.

I've replaced both caps and repaired the trace. Now I'm getting sound out of the left speaker but the right speaker and subwoofer don't seem to be working.

Could someone that knows more about these boards advise?

Many thanks in advance.
 
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On a creature the left and right speaker are linked. One is midrange and tbe other on the right is high end (a tweeter).

So if the left speaker works - check the cap on the tweeter, or measure tweeter disconnected on a meter and check how many ohms it is reading.

I would be looking for further damage and maybe even the sub output chip failed.

Also check all voltages on the board. Do you have schematic?
 
Pick Holder said:
On a creature the left and right speaker are linked. One is midrange and tbe other on the right is high end (a tweeter).

So if the left speaker works - check the cap on the tweeter, or measure tweeter disconnected on a meter and check how many ohms it is reading.

I would be looking for further damage and maybe even the sub output chip failed.

Also check all voltages on the board. Do you have schematic?
Click to expand...

Logically that all makes sense but as far as I know all speakers were fine before the audio board died so I would be surprised to find the issue anywhere other than the audio board.

Thoughts?
 
According to the pinwiki the caps that failed on my board (C26 & C28) are part of the +12V and -12V section.
 
Pick Holder said:
No thoughts except 20 years as a pin engineer and 35 years as an audio engineer.
Click to expand...

I’m not doubting your knowledge Phil I’m just saying this is my personal game and the speakers were fine prior to the audio board failure so feel fettling with the speakers would be a waste of time. I would expect the failure to be something else on the audio board I have missed. I’m just not sure where to start.
 
Stepping in as an arbitrator.
I think Phil is saying that if one back of speaker works then the other should work.
Ruling out a back box speaker because it worked before caps popped could be relying on something else not going wrong.
Can you test them by moving the whole panel to another machine?
 
Calimori said:
Stepping in as an arbitrator.
I think Phil is saying that if one back of speaker works then the other should work.
Ruling out a back box speaker because it worked before caps popped could be relying on something else not going wrong.
Can you test them by moving the whole panel to another machine?
Click to expand...

Is the panel wiring the same in White Water? If it is I could move the whole panel into my white water.

Or alternatively I guess I could swap around the audio boards?
 
Yes, pretty sure that will work. I have put BSD’s whole panel into CFTBL to test a DMD and speakers. All similar wpc stuff. The audio board should work too but it will have sound roms to swap so a bit more effort
 
It was less effort to swap the audio boards due to all the cable ties so that’s what I have done.

Interestingly same results with the White Water audio board in the CFTBL I’m still only getting the left speaker working. Right speaker and sub not working.

So it seems as Phil suggests and surprisingly to me something else is at fault.
 
Well clearly I’m not worthy of anymore of Phil’s time but I’ll just update you anyway.

I’ve taken a reading of the right speaker (the tweeter) and it looks like it’s a dud. Perhaps it never worked and I’ve just not noticed.

I’ll replace the tweeter and then take a look at the subwoofer if needed.
 
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