sony model : kv-32s12
transistors : Q601 and Q602
original transistor number(oem) : 2SC4834N
cross reference trans. number: NTE2582
after the original transistors blew ( cases blown apart and a short between
base -emitter ). I replaced them with NTE2582 and checked all components
within that section to be good. reassembled tv and powered up. The tv
operated correctly and transitors ran cool to the touch for approx. 2 min.
then the transitors blew without warning. once again I rechecked all
components, resistors caps diodes to be good.
Anyway, where are these transistors in the circuit? In many
cases, there are downstream circuits that can cause overloads.
Right now I have a similar case in a high voltage sections of a
single tube projector. The high voltage transistor blows. A
new one will work for a few minutes and then die also. However,
when I say work, the unit powers up, but the transistor goes so
quickly (a few seconds) you really can't see if the unit is
working. Right now I am thinking a short in the flyback. You
have to think about other circuits. If, in the 2 minutes of
working, everything is really working properly, and the
transistors in question stay cool, then something must be
changing to pull too much current, etc. And as you point out, a
large current because the literally blow apart. Again, you must
look at what the circuit it doing. You do have a schematic,
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