UA-5002 transformer in MC76 (Purple Audio)?

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Hayman

Well-known member
Joined
Dec 1, 2004
Messages
91
Hi,

I have two MC76 kits that I'm about to finish. When I purchased the kits I ordered them without the output transformers. I have two UA-5002 transformers that I planned to use......if that can be done?

Anyone know the colour code of the UA-5002?


Thanks

Richard
 
they should work. if UA followed the urei color codes it should be easy. just match the wire color to what is screened on the board, except for the orange one. then put the red wire in the hole labelled orange. if you have a pair of wires leftover, orange and yellow, tie them together.

good luck and feel free to ask any questions you have about the kit.

ed
 
[quote author="edanderson"]they should work. if UA followed the urei color codes it should be easy. just match the wire color to what is screened on the board, except for the orange one. then put the red wire in the hole labelled orange. if you have a pair of wires leftover, orange and yellow, tie them together.

good luck and feel free to ask any questions you have about the kit.

ed[/quote]


The color codes look right. When you say tie the two leftovers together, do you mean solder them together?


I have one more problem: The color codes on my power transormer do not match what is screened. I have black, red, orange and yellow for secondary (not blue, black, blue). I have blue, grey, violet and brown for primary. It is the transformer suggested on the Purple Audio site (farnell nr. 4301341)


Anyone have a close up picture of a finished power section of the board?


Thanks

Richard
 
Also....


I have these two:

Clarostat.gif



The black one came with the kit. How would they be different?

Richard
 
yes, if you have an orange and yellow wire on your audio output transformer leftover, solder them together and insulate the connection with heatshrink or tape. note that the PCB says "orange" where you should actually put the red wire.

you should look at the transformer diagram on the side of the power transformer and compare that to the schematic in the mc76 manual so that you understand what you're doing. ignorance is not your friend when dealing with potentially lethal line AC.

the larger diameter wires are the primary and the smaller ones are the secondary. put the black and yellow secondary wires in the two holes marked "blue" and put both the red (pinkish) and orange together in the hole marked grey. for the primary, put brown in "white", violet in "yellow", grey in "orange", and blue in "black".

as for the attenuators, in practical use there is no difference between the two kinds. the three deck one we use costs more than a two deck pot, but the correct taper for the two deck version is no longer available.

ed
 
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