5 Mar
2019
5 Mar
'19
9:06 p.m.
On Wed, Mar 6, 2019 at 12:16 AM Alan Perry via cctech
<cctech at classiccmp.org> wrote:
For a little background, I had run the system for about 15 minutes, then
it sat for a couple months while I removed the PVA from the display,
then, when I tried to run the system again, the system started to boot
and then the circuit breaker popped.
This is a switch mode power supply with all the failure modes that that
implies :-)
I'd start by checking the mains bridge rectifier (actually used as a pair
of diodes in a voltage doubler circuit on 110V mains), the mains
smoothing capacitors (820uF?) and the BUV47 chopper transistor. If
the last is short-circut then it's very possible it was damaged by a
fault elsewhere in the PSU.
-tony