Standby B + too high on a GE 27" T.V.

[Dani]

Model # 27GT616 Chassis # CTC 185 AB3. Unit was dead, horizontal output
BUH517 shorted, Q 114 PWM regulator was shorted, Q 4116 in PWM open
totally, now the standby B+ to the horizontal is + 165 volts DC, it's
about
+ 130 volts while running, & all seems ok. Isn't this too high while in
standby?
Thanks, Dani.

 

[on1aag]

Dani schreef:

Model # 27GT616 Chassis # CTC 185 AB3. Unit was dead, horizontal output
BUH517 shorted, Q 114 PWM regulator was shorted, Q 4116 in PWM open
totally, now the standby B+ to the horizontal is + 165 volts DC, it's
about
+ 130 volts while running, & all seems ok. Isn't this too high while in
standby?
Thanks, Dani

Hi Dani,

When a pwm regulator is not loaded, the output voltage will rise.
There is nothing unusual about that, but... you should check if the
output voltage
of the pwm regulator is not higher than the working voltage of the
electrolytic capacitor
at the output of the regulator. If it is too high you should check if
the bleeder resistor
across the capacitor is not open circuit.

on1aag.