Calling Yamaha A-1 Owners. Recap Info
I have three A-1's, recapped one of them a while back, the other two I acquired for next to nothing from an owner who had previously sent them out to be repaired as they were apparently not working, but they were sent back to owner butchered and in worse state and still not working.
For instance, many lytics were replaced with totally wrong values(some the wrong way around), eg one lytic i found in there was 1000uF in place of original 470uF!
Also found the two 18000uF filter caps were removed and in their place were four 2200uF caps! 2 caps wired together to make a total of 4400uF each pair. Unbelievable.
One of the boards was also a mess, with broken tracks being jumpered with wires and soldering which was an absolute mess.
Just take a look at the attached photos to see what I mean. I have a lot of work here to do by the looks of it.
See photo 3 how this dude attached the two transistors, in the fourth photo how it should be from same board from one of the other A-1's.
Anyway,I need clarification on one of the caps as to their values. In the service manual, C212 is shown in the parts list as 1000uF/50v, but in the schematic it is shown as 10uF/35v.
C212 in the two non working ones are 10/25(though not originals) and in the one I recapped is 10/35.
So my question to anyone who has an A-1, are you able to confirm what the actual value should be.Should it be 10uF or 1000uF?
I tend to think it is 10uF.
The board with the C212 cap is NA07041(power supply board), which is held by a couple of rubber tags at the top and is easily pulled up and out of the amp if need be to check.
Any help here is highly appreciated.
I have three A-1's, recapped one of them a while back, the other two I acquired for next to nothing from an owner who had previously sent them out to be repaired as they were apparently not working, but they were sent back to owner butchered and in worse state and still not working.
For instance, many lytics were replaced with totally wrong values(some the wrong way around), eg one lytic i found in there was 1000uF in place of original 470uF!
Also found the two 18000uF filter caps were removed and in their place were four 2200uF caps! 2 caps wired together to make a total of 4400uF each pair. Unbelievable.
One of the boards was also a mess, with broken tracks being jumpered with wires and soldering which was an absolute mess.
Just take a look at the attached photos to see what I mean. I have a lot of work here to do by the looks of it.
See photo 3 how this dude attached the two transistors, in the fourth photo how it should be from same board from one of the other A-1's.
Anyway,I need clarification on one of the caps as to their values. In the service manual, C212 is shown in the parts list as 1000uF/50v, but in the schematic it is shown as 10uF/35v.
C212 in the two non working ones are 10/25(though not originals) and in the one I recapped is 10/35.
So my question to anyone who has an A-1, are you able to confirm what the actual value should be.Should it be 10uF or 1000uF?
I tend to think it is 10uF.
The board with the C212 cap is NA07041(power supply board), which is held by a couple of rubber tags at the top and is easily pulled up and out of the amp if need be to check.
Any help here is highly appreciated.
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