Can someone verify this issue with the output PCB?

As a reminder; this BM4000 type 2408 Login to view imagewas modified by the previous owner and I am trying to get it back.

I've had to go through everything since things were added and now I think, moved around.

I need help to verify if these CAPS and resistors were swapped or is this the way they should be on the circuit? They do not match the semantics that came with the unit.

Thank you for your expertise.

dj

There are several different versions of Beomaster 4000.
You cannot always be 100% sure, that the included schematic is the correct one for your specific version.

I suggest you check the solder side and compare to the schematic.

Martin

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This is the solder side. It looks like they are in series so I guess it won't make a difference.

Hi All:

I just ran into two more items that are not on my schematics for the BM4000 and would like to know if they should be removed or left alone.

These are two CAPS (1uF 35v) that are on the solder side of the FM PCB. They look original so I just need guidance from those more knowledgeable than I am. Martin, these were not identified on your kit nor did you provide a replacement for them.

Thanks for your responses.

dj

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So now we have proof of an extra-tantalistrial situation! ❓😂

Far from all production changes, sub-revisions, aftermarket modifications and territory specific versions are equally well documented.
Some aren't at all, which makes putting together the kits quite a task and feedback and information from owners valueable.

I agree they look original, but I cannot tell you exactly why one tantal was added across TR18 C-E and another to decouple the supply to part of the IF.
The latter could be to counter for a particularly troublesome batch of IF Amp ICs (OpAmp  CA3012). I can't say.
Perhaps that could explain both of the tantals, really.

Of course I will look into this and see, if the kit should be updated with this info, as I always do when new information turns up.
Can you tell me the serial number of this Beomaster 4000?

I will happily send two new tantals to you, just say the word, but if on the bench here I really wouldn't worry about leaving both of them in place.

Martin

Thanks.
This makes it a very late production individual.
No voltage setting switch, so an export (US) version as well.

Martin

Can you give me a little more insight on why this does not affect the operations of this part of the circuit when one of the ACs is switched with the negative pin? (Please forgive me for the inverted text on the schematics).

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