Pass. p1.p preamplifer china help

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Hi, I bought a pcb made in China x Pass Aleph p1.7 complete with relay volume control on Ebay. Now, from the template provided, you don't understand some components well, can you help me? thank you (5551 ??) ( 431 ?? )
 

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I have the bare pcb affixed to use quality components ... and the psu scheme and preamplification and likely ... the problems I encounter are only in the recognition of the component indicated as 5551 and 431 that deal with the control of the relay volume. . xi 5551 I find only correspondences with 2n5551 but the pinout seems to me wrong. x 431 I can't find any matches .. thanks:):):)
 
I have the bare pcb affixed to use quality components ... and the psu scheme and preamplification and likely ... the problems I encounter are only in the recognition of the component indicated as 5551 and 431 that deal with the control of the relay volume. . xi 5551 I find only correspondences with 2n5551 but the pinout seems to me wrong. x 431 I can't find any matches .. thanks:):):)


If you dont get help from the supplier. A good Point to start is to make a circuit diagram from the pcb.
Only the volume Control part.
The chinese copycats will have cloned the preamp part 1:1 so there you could Need the Service Manual.

Maybe with a Diagram the parts you Looking for become clearer
This is what i would do.

Will be some work but...
...but better than nothing.
 
But... I would not start a thread just for my question, really. Is there any active thread with such subject that you are following and giving a bit of time, eventually could give me help?

Maybe PMs works better this case?

And btw, the red eyes may need some Visine, especially at mornings :)
Thanks,
 
If it is the board I think it is, you can use the original parts. I think the cbe pinout of the small transistors is different to the ztx450/550 layout so you will need to twist the legs (use teflon sleeves to avoid contact).
I suggest you take hi-res photo of the front and back of the board. Then in software make a mirror image of the rear. It is then easy to follow the traces and compare with original schematic.
I built an AP1.7 using a similar board that was given to me. Works great. Search for my postings to see more, also about finding (and fixing!) oscillations.
 
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