afternoon/morning all.
a little help if you please
i am trying to fix an smps from a digital mixing desk.
it has 5 voltage rails from 2 transformers.
1 transformer is clicking (hickup) and the output voltages are fluctuating
what i ahve done so far.
all electrolytic capacitors replaced.
replaced opto coupler and tl431
replaced ob2269c pwm ic (last resort)
all resistors tested for correct value.
all diodes tested against short.
zenners tested as far as not short.
confimed aux winding voltage output.
confirmed signal into and out of opto isolator
i cannot find any shorts or open circuits.
i have no way to ,confirm values of smd ceramic capacitors only that there are no shorts.
what am i missing?
thankyou in advance
a little help if you please
i am trying to fix an smps from a digital mixing desk.
it has 5 voltage rails from 2 transformers.
1 transformer is clicking (hickup) and the output voltages are fluctuating
what i ahve done so far.
all electrolytic capacitors replaced.
replaced opto coupler and tl431
replaced ob2269c pwm ic (last resort)
all resistors tested for correct value.
all diodes tested against short.
zenners tested as far as not short.
confimed aux winding voltage output.
confirmed signal into and out of opto isolator
i cannot find any shorts or open circuits.
i have no way to ,confirm values of smd ceramic capacitors only that there are no shorts.
what am i missing?
thankyou in advance