Baird X32DTV

[Davy]

Have Baird X342DTV stuck in standby (blue light)

Uses-: Phihong -  PS22-417-R power board
          Main board-  PY12038 Hair 2006
       
Changed all caps on psu... wondering if there's a firmware flash anywhere, can't seem to find any.
5V supply is good, nothing on the 24V inverter rail and about 3.2 on the 12V rail, not having any circuits I guess this might be from the s/by supply.

The power supply powers up minus backlight when supplying the 'power on' voltage

Worth trying a new eeprom dy'a think?

Dave

[jordan]

Problem with inverter board

[Davy]

Thanks Jordan, you're a gem.

We'll dig him out and have a look... thought they gave error goods.

Dave

[Davy]

Inverters OK..!

I can 'force' the main power supply ON along with the inverter , backlights are OK.

There is one hiccup on the main board that nearly foxed me a 1501-50 switching regulator, it was marked 12V on the output on the pcb  test point, seeing three electrolytic's on the line was rated at 25Vdc I thought 'Eureka'.... but the 1501-50 is only a 5 Volt regulator looking at the data sheet, just my luck the voltage was 5.09V.

Thank you for trying though.

Dave

[t1412]

hi davy i've got one in with stuck in standby fault, opened  it up found to caps swollen changed them now the picture is strobbing 12v line is .8.9 volts i 've got a funny feeling the caps i've put in are no good so i'm going to change them

regards
shaun   

[Turnip]

Hi - Shaun,

Had similar prob with a 47 inch version, where after a backlight cut I got all 4 inverters from Fleabay, and the backlight  cut again after a few minutes.

Suspect a PS22-417-R problem, but none yet on fleabay 

Might just well be a M/B prob - Chris

[Davy]

Applying about 3V to the power ON pin AND the back light ON pin will tell you if they and the other voltages are in good shape.

Either something wrong in the 12V department, or something pulling the 12V down of it's only reading 8.9V, could be diode could be caps, my guess this is where the 'strobings' coming from The power supply will run off-load if forced ON.

Could do a current check on the 12V if that helps. I noted on my 12V there's about 3V when plugged in, until I force the power supply ON then I get the 12V.

My set just sits idly in blue light s/by, dunno whether to try a new eeprom or not,  is there an eeprom flash any be had anywhere?

Dave

[t1412]

hi turnip thanks for the heads up, it's on the bench l 've had 2 weeks now, thought nice easy one been a nightmare, the caps i used were nic ones has i only had these in my box the ones i took out were samxon i'll see if i can get a main board, see if this the problem thanks

regards
shaun
  

[Davy]

Them caps need be 105deg. C low ESR types.

Dave

[Turnip]

Hi Davy,

Changed all them caps with 105 Low ESR  types, and the Ebay replacement 4 x inverters still cut out after a few minutes, as the old one's did - bit puzzled.

Guess problem might be elswhere - not at all sure where.

Thanks Davy.

[Davy]

Hi Turnip.
The CCFL's could be the cause, one of the transformers or even the small pF coupling caps...... not saying it is. Never had a transformer go on me yet but sure have had coupling caps doing that.

Have you no spare tubes you can hook across to check? That is what I usually do, I know it's a pain but it does prove a point....

pity you couldn't load the inverter with resistors instead of tubes - dunno what kind of current they draw, you'll need high voltage resistors and resistance high values, but you'll need one for each tube, might even have a play, sure would save a lot of time and guessing.

Take note how the tube lights, if they light fairly even, do they flicker will point towards the tubes or inverter. Since you've had capacitor troubles, hows the voltages, especially the inverter supply? They are usually within a midgets whisker either way - so to speak.

In my case, I tried a new eprom to no avail my guess is the data lines being clogged up, so I'm gonna have to try another main board.

Edit:
I seem to think these sets comes under Baur brand as well as Baird.

Dave