Jerry,
So what causes the pass transistor to fail? (my crowbar is after the pass,
in the cable... added after the first fail took out half the IC's on my
Omni back in 1980 (under warranty, thankfully)... if my crowbar trips, it
is because the pass has failed and it is protecting the rig, not to protect
the pass transistor).
To that end, I seem to get a fail every couple of years. Is that because the
252 was "under designed" i.e. not enough headroom in the 2N5301? too small a
heat sink for the application?
If so, what is the best way to beef up the design? up the device? add a fan?
(and yes, obviously, I could just go out and plunk down for an Astron 35...
this rig has sentimental value, and I like running it as the original
set-up)
Bill
W1PA
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