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Jason D.
 
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Default REQ: Toshiba D1555 HOT

On 11 May 2004 04:00:06 -0700, (Obone) wrote:

Hi all... If someone has this transistor (known good), I would greatly
appreciate its DMM readings (ie. +/-B-E mV, +/-B-C ohms & +/-C-E mV).
TIA, Obone.


Typical diode drops with diode check and resistance measurements
should show open or megaohms, other way less resistance except for
that built in resistor.

This has both resistor across C-B and diode damper across C-E, if it
shorted (much less than 50 ohms typically for the internal resistor.
Every shorted horizontal transistors I come aross always are extremely
low like 1 ohms or less and usually on all 3 pins.)

Need to find the reason for blowing that HOT. External causes:
bad solder connections in base driver circuits (yes whole), dried up
capacitor for the B+ supply for the horizontal transformer driver for
the base of D1555. Any horizontal circuit problems (including flyback
transformer even it's secondary circuits may cause HOT to fail) Many
time problems in horizontal circuits HOT fails instantly, just like
that: snap!

Cheers,

Wizard