HY9 is a Zener for ? voltage

[budm]

Re: HY9 is a Zener for ? voltage

So QB102 Gate discharge transistor is also bad?

[capwizard]

Re: HY9 is a Zener for ? voltage

Yes, QB102 marks H2A is a PNP Tr, shorted at Collector and Emitter.

Each parts are coded (or no mark) really time consuming to repair.

[capwizard]

Re: HY9 is a Zener for ? voltage

Question? i forgot put CB113 back but PCB works(has DC12v), what is the CB113 for?

[budm]

Re: HY9 is a Zener for ? voltage

Question? i forgot put CB113 back but PCB works(has DC12v), what is the CB113 for?

It is connected in series with the resistor to form RC snubber for the rectifier diode, you better put that back in place.

BTW, that GATE discharge Transistor tested off board as shorted E-C? I am surprised that the SMPS IC output drive was not damaged too.

[capwizard]

Re: HY9 is a Zener for ? voltage

RC snubber for the rectifier diode, you better put that back in place. I did.

Now TV (NS-29D310NA15) is under testing, underneath PCB was the one I ordered on ebay( is good).

Question : Why the TV is in setup mode? TV came with no standby.

[capwizard]

Re: HY9 is a Zener for ? voltage

Because someone swaps the EEPROM that was me..............

I thought it is the EEPROM....then I found out TV does not has 5vSB................

[budm]

Re: HY9 is a Zener for ? voltage

Because someone swaps the EEPROM that was me..............

I thought it is the EEPROM....then I found out TV does not has 5vSB................

Another priceless tip for you, after visual inspection ,and some checking of the fuses or protection devices, then check the Voltages and see if they are present or present with correct Voltages or not, no Voltages no working.

[capwizard]

Re: HY9 is a Zener for ? voltage

Thank you. With your tip I can save 1 day's troubleshooting.....

This one PCB TV has no connector for testing 5vSB when I check 12 V does has Vibration voltage. After I change EEPROM still not works then I check no 3.3v.


NUP 37R : https://www.badcaps.net/forum/showthread.php?t=60813

[gabiz_ro]

Re: HY9 is a Zener for ? voltage

Stand-by voltage must be present on Vcc of SPI Flash memory,on Vcc pin of IR receiver.
Easy to check if PSU is inaccesible.
On some units is 5V in other is 3.3V

[capwizard]

Re: HY9 is a Zener for ? voltage

Thank you, I forgot about it. (IR receiver or Buttons)

[budm]

Re: HY9 is a Zener for ? voltage

Thank you. With your tip I can save 1 day's troubleshooting.....

This one PCB TV has no connector for testing 5vSB when I check 12 V does has Vibration voltage. After I change EEPROM still not works then I check no 3.3v.


NUP 37R : https://www.badcaps.net/forum/showthread.php?t=60813

Well, that come from experience to be able to section out the board to see where the STBY power supply is and look at the cold side of the transformer where the rectifiers are to see if it is alive or not.