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Heinz Schmitz Heinz Schmitz is offline
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Default Horizontal O/P Transistor (TV)

Sam Goldwasser wrote:

- out of circuit transistor measuring 45 ohms in both directions (base -
emitter)


Sounds bad. Should depend on polarity. What voltage does
your meter put out in Ohms range?


Probably OK. If it has a built-in damper diode, will have ~50 ohm internal
B-E resistor.


Sam, I just took a new 2SC4924 (npn HOT in some CRT monitor).

This had R(BE) 14 Ohm vs infintiy (*) with an ohm meter putting out
2.5 Volts in the x1 range.
(*) meter connected one way vs the other

Setting a resistor with 42 Ohms parallel to BE, I measured
13.5 Ohms vs 42 Ohms.

That is, even if there is an internal base-emitter resistor of ~50
ohms, it is still possible to check by resistance measurement
wether the BE junction is ok.

Regards,
H.