bush lcd23tv022x

[sparky]

hi
 have his tv fault sound ok no backlights, checked 24v psu,replaced
inverter all volts ok any ideas
thanks dave

[Turnip]

Hi Dave,

Don't have it listed, so what is it, and some piccies for the folks, perhaps  ? - Chris

[sparky]

hi
gone back to cust screen faulty one of
tubes faulty
dave

[Turnip]

Hi, Sparky,

Must admit haven't yet had a dud tube - just Norfolk luck perhaps - Chris.

[sparky]

hi chris
according to cust when i took it back ,to get pic on
she used hairdrier on front for 15 mins screen got very
hot then the pic would come on when she switched on
stange
dave

[ProDave]

Most inverters will power up for a couple of seconds even if there is a dud tube.  Most of them inhibit all the over current or over voltage protection for a couple of seconds to enable the tubes to strike.

The fact you are not seeing the screen, or even the tubes light up for a second or 2 at power up suggests something different.

I had a set recently where the main board was not sending the "on" signal to the inverter.  By swapping parts around with another identical set, I found the faulty set also had a stuck pixel line on the screen, so I didn't bother trying to fix the fault, I just scrapped the set.

[daz]

hi all
had duff tubes many times, usually on the acoustic solutions + whafedale sets, all tubes will start for a second or two then shut down, do this a few times until they warm up and set will run all day. having the set in a warm room also helps. finding out which tube is causing the fault is a pain as substitution seems to be the order of the day. read somewhere (possibly on this site) fault is caused by uneven distribution of mercury in the tubes during manufacture.
has any one used one of those tube testers yet, any good?
daz

[Turnip]

Hi Daz,

Good thought, as I have had some where backlight cut after a few seconds, and replacement invertor, and P/S caps didn't do the biz. Never thought to pre-heat the screen, just P/S caps.

Thanks - Chris.

PS - can't afford a tube tester.

[sparky]

true money in short supply not only that if any damage to lcd screen
while changing tubes it still scrap,time and  money wasted
dave

[Turnip]

Hi folks,

Was thinking of knocking up a cheap tube tester out of scrap but have not yet taken a screen apart to check tube wiring. Note that some sets use just a couple of connections for the lot, others seem discrete with perhaps a pair for each tube.

Any thoughts ? -  Chris

PS - With any luck might just flog Dave (the optomistic one) - cheapish.