If the amp has been worked on before and you do not know its history then all bets are off... you have to start at the beginning.
R1 is one of a pair of parallel 0.22 ohm resistors. If they are burnt/open then the FET's have conducted heavily and have quite possibly failed.
I think you need to look the amp over visually and try and determine what work has been done and whether the correct value parts are fitted. The big question is whether the amp was OK before the recap.
Testing involves always involves using a DBT (dim bulb tester) to limit damaging currents.
It is a complex amp and one that is not very forgiving.
If the FET's have failed then typically they will read very low ohms between drain and source.
R1 is one of a pair of parallel 0.22 ohm resistors. If they are burnt/open then the FET's have conducted heavily and have quite possibly failed.
I think you need to look the amp over visually and try and determine what work has been done and whether the correct value parts are fitted. The big question is whether the amp was OK before the recap.
Testing involves always involves using a DBT (dim bulb tester) to limit damaging currents.
It is a complex amp and one that is not very forgiving.
If the FET's have failed then typically they will read very low ohms between drain and source.
The left FETS have failed. The big R1 is intact but the LK-thingie beside it was burnt.
The amp worked after the Mundorf 10000uf was fitted. Problems arose after the 10 pieces of 25v 100uf was fitted as I understand it. Problems with the light staying amber and not turning green. As I left it on for a while it started blowing fuses.
I can´t figure out the original capacitor values so if anyone here has the amp maybe you can enlighten me. Or is the specs exactly as 7R?
The amp worked after the Mundorf 10000uf was fitted. Problems arose after the 10 pieces of 25v 100uf was fitted as I understand it. Problems with the light staying amber and not turning green. As I left it on for a while it started blowing fuses.
I can´t figure out the original capacitor values so if anyone here has the amp maybe you can enlighten me. Or is the specs exactly as 7R?
The service manual seems to suggest the power amp stages are the same between the different versions.
The service data I was looking at was from HiFi Engine which is free to use (once you register).
HiFi Engine | Owners and Service Manuals
You would have to look at everything that might have been replaced in the past and determine if errors have been made. Also such things things as polarity of the caps need checking.
The service data I was looking at was from HiFi Engine which is free to use (once you register).
HiFi Engine | Owners and Service Manuals
You would have to look at everything that might have been replaced in the past and determine if errors have been made. Also such things things as polarity of the caps need checking.
but work slowly and check all your work as you go along.- Status
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