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.
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