Thread: Pye 37K7225
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I.F.
 
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Default Pye 37K7225


"DRead" wrote in message
oups.com...
Yes does sound as though it is trying to restart.
Any idea's?


Horizontal scan transistor maybe S/C?

Horizontal scan transformer maybe shorted turns or insulation breakdown?

Horizontal scan flyback tuning capacitor S/C

The tuning caps often crack or split when they fail, and you should have
done a thorough visual inspection by now anyway! Try disconnecting the
collector of the scan transistor - first test it for S/C then try powering
up with it disconnected. Note that the PSU may not take to being run with no
load so try connecting a 40W or 60W bulb from the feed to the collector to
chassis (GND) See if the PSU fires up and lights the bulb and it wasn't a
S/C transistor, this points to either shorted turns in the transformer or a
load on one of the scan derived supplies S/C - such as audio or vertical
sections. If the PSU still won't fire up its likely the scan transformer
primary winding is shorted to GND or the PSU itself is faulty!