My Quad 303 won't switch on and I'm just checking I'm on the right track, checked dc at main caps and got nothing
Confirmed 230vac to transformer,
Disconnected transformer secondaries from bridge and got
46vac
7.5vac
Connected them back and disconnected vdc from bridge rectifier and got
On the vac 48v and 8.1v
on the vdc outputs on the bridge measures 2.5vdc on both
I'm leaning towards a faulty bridge rectifier?
Does this sound correct?
Confirmed 230vac to transformer,
Disconnected transformer secondaries from bridge and got
46vac
7.5vac
Connected them back and disconnected vdc from bridge rectifier and got
On the vac 48v and 8.1v
on the vdc outputs on the bridge measures 2.5vdc on both
I'm leaning towards a faulty bridge rectifier?
Does this sound correct?
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Seems more like a shorted turn in the secondary. Fully loaded you should get about 90VDC across the PSU caps, ~67VDC from + to ground, and about -23VDC from ground to -.
I'm getting nothing but 2.5vdv from the bridge.
How much AC should I be getting from the transformer unloaded, 48vac seems right? But 8.1vac on the other side?
How much AC should I be getting from the transformer unloaded, 48vac seems right? But 8.1vac on the other side?
Ok seems to have resolved itself, reconnected all wires and.... just turned on?
Now new issue, cannot set the center voltage on one of the driver boards, R130 was open and couldn't get voltage over 25vdc now replaced and cannot get under 40vdc, voltage at R111 is 5vdc so incorrect there, where should I be
looking?
Now new issue, cannot set the center voltage on one of the driver boards, R130 was open and couldn't get voltage over 25vdc now replaced and cannot get under 40vdc, voltage at R111 is 5vdc so incorrect there, where should I be