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Toshiba 32C3030D - Cycling.

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Turnip:
Hi folks,

Got one in where at switch on the Green Led lights - If menu pressed, get display for a few seconds then it disappears - At the same time the sound hisses then goes off. Set cycles continually.
Checked PE0252 Power board where voltages are correct and stable.

Note PE0253 Sub Power has several Buck converters, some of them canned. Wonder if anyone has had the problem ? - Thanks - Chris.

Davy:
Here's the service manual if you haven't already got it.
http://elektrotanya.com/toshiba_32c3030d-02.zip/download.html Clicking 'Get Manual'.

When you say there's 'canned converters' was they included in your voltage checks? Trouble is the voltages may well read OK, but what if there's hash or ripple due to bad caps, can you scope them?

The hissing volume don't sound right.... could it be a corrupt Eprom I wonder??  I'm thinking if there's a fault the set would just shut down or give an error code.

Dave

Turnip:
Hi Dave and thanks.

Have the manual but suspicious of the sub-power board as have had problems with other Toshiba sub-power boards where the buck inductors were dry jointed, and whacking the panel pointed out the problem.

This one has the buck PCBs in vertical screened cans, but can find no dries on inspection. Note Fleabay sells the panel for peanuts so guess probably not the problem, but ordered one anyway just to rule it in or out.

Could well be that sound is set to max, and with no identified input could hiss a bit. Can't try input select as set doesn't stay on long enough.

Tend to agree it's probably not a firmware issue due to the cycling biz. As most panels are really cheap can try several to try sort it - Thanks again - Chris.

Davy:
With no signal the sound should be muted wouldn't it, no matter what the volume level?

Guess what I am trying to elude to is using this 'hiss' as a clue, is the set starting up and then shutting down, would hash and ripple on the supply or something arching cause the sound to 'hiss'. It could be something the firmware is not happy with causing the cycling,  Eprom corruption comes to mind.

I'd be scoping all the supply lines for hash and ripple which would upset a digital apple cart first of all or try a known good power board which is easier said than done, if any of the supplies are not up to par with digital anything can result... a test meter will only measure the voltage and not the 'crap' on it.

Dave

Turnip:
Hi Davy and thanks,

Seems this set has known firmware issues (I didn't know - just told) so guess you're right.

Think go for replacement SSB and DVB boards as are incredibly cheap on the Flea.

Agree about PS ripple, can give corruption issues, but this set isn't known for it, Perhaps as PS and a sub PS sorts most ripple problems -

Thanks, think get a few 24C64 so might sort the next one if that's the issue - Chris.

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