I've just bought a Dynatron 1275 that has 2 faulty amp boards.
http://is03.thegumtree.com/image/extrabig/146940419.jpg
One board has a fault that causes a hum (sounds too soft to be 50Hz) and doesn't output the original audio signal, then blows the main 1500uF capacitor (I replaced it once).
The other has static low-frequency rumbling (sounds like the record player idling, even when the volume is down and nothing is moving).
I've attached a circuit diagram if anyone can diagnose the issues from my descriptions.
Both boards look to have been repaired a few times, and have signs of heat damage.
Failing fixing the boards, I'm considering swapping the boards out for a pair of Quad 405's. Both run on 50V, and I thought it might be an interesting upgrade.
Any advice?
http://is03.thegumtree.com/image/extrabig/146940419.jpg
One board has a fault that causes a hum (sounds too soft to be 50Hz) and doesn't output the original audio signal, then blows the main 1500uF capacitor (I replaced it once).
The other has static low-frequency rumbling (sounds like the record player idling, even when the volume is down and nothing is moving).
I've attached a circuit diagram if anyone can diagnose the issues from my descriptions.
Both boards look to have been repaired a few times, and have signs of heat damage.
Failing fixing the boards, I'm considering swapping the boards out for a pair of Quad 405's. Both run on 50V, and I thought it might be an interesting upgrade.
Any advice?
