Request for Adcom GFA-555 MkII schematics

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Hi,

My Adcom GFA-555 MkII is blowing supply fuses on the L channel. I found some GFA-555 schematics here but they don't match what I found on the actual PCB. Even the reference part numbers are wrong.
Adcom has also used their own part numbers on the devices making it even harder.

Can someone kindly share a GFA-555 MkII schematic and parts list if they have one?

Thank you in advance.
 
Hi trluser.

Input power amplifier.

GEirin
 

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trluser said:
Hi,

My Adcom GFA-555 MkII is blowing supply fuses on the L channel. I found some GFA-555 schematics here but they don't match what I found on the actual PCB. Even the reference part numbers are wrong.
Adcom has also used their own part numbers on the devices making it even harder.

Can someone kindly share a GFA-555 MkII schematic and parts list if they have one?

Thank you in advance.


Did you ever find the parts list?
I have a bad amp as well and suspect the input side.
Of the schematics I have seen, they were too small to read.

Can someone tell me what values correspond to the numbers on the input board capacitors?



One listing says C101 and C151. THey look like big pink square blocks. I have never seen a capacitor that was a pink square.
The do not measure like most capacitors. They both have a fixed resistance of around 1000k ohms, they don't change value on my multimeter diode setting. What does that mean? IS this really a resistor?
 
C101/151 are 1uf@100v. They are not your problem and do NOT change them unless they are shorted and I am sure they are not. They are Polycarbonate,very high quality and not easy to find. I assume from your post (big pink square blocks) you do not have much experience with electronics. I would suggest you take your amp to a good repair shop for an estamate. I am not trying to be rude but it dose not take much to turn a simple repair into a very expensive one. Do you have a working scope. function generator and DVOM? the basic equiptment?

 
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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.