The 2.5AT mains fuse F601 keeps blowing. The last time
this occurred, smoke appeared to come from the c.r.t. base
connector. Could the trouble be due to tracking here?
It’s unlikely that tracking on the c.r.t. base panel could
blow the fuse violently. We suspect that the smoke is
coming from R607 and R608 on the power panel below the
c.r.t. neck, in which case the following devices (gate- controlled switches) should be checked and replaced as
necessary: the starter and regulator GCSs Q602 (SG609)
and Q603 (SG608), and the line output GCS Q510
(SG608). The later equivalent of the SG608 is the SG613.
As these devices are rather expensive, it would be best to
start the set up gently after the repair, using a variac. You
should see something on the screen at an r.m.s. mains input