Any tv repair experts in t'house
Discussion
I have a panasonic 28" widescreen tx-w28r4dp which when turned on thinks for a second or two and then switches itself off into standby mode... any advice along the lines of "ah, that'll be the kerchiga and all you need to do is..."?
It'll do the kids good not to have scooby doo on tap but if I don't get motogp I'm as grumpy as buggery.
Regards,
Mark
It'll do the kids good not to have scooby doo on tap but if I don't get motogp I'm as grumpy as buggery.
Regards,
Mark
Had a similar problem on an old(ish) Furgerson.
If you take the back off, somewhere near the power input you should find a small fuse (it may be in a covered box). It looks like a normal household fuse but it isn't. You'll need to go to Maplins or a TV repair shop to get a replacement.
Get a few because if it is that, then it will go again. Something to do with static build up!
Of course it may not be that but it sounds very similar!
If you take the back off, somewhere near the power input you should find a small fuse (it may be in a covered box). It looks like a normal household fuse but it isn't. You'll need to go to Maplins or a TV repair shop to get a replacement.
Get a few because if it is that, then it will go again. Something to do with static build up!
Of course it may not be that but it sounds very similar!
Zad said:
Line output transistor rather than transformer. Possibly taken the recovery diode out too. Nothing you can do about it though, get a telly repair bloke out for a look.
Mike
Line output transformer = LOPT or flyback transformer. The bit that turns mains voltage into the nasty 20kV-30kV that exists within TV sets to power the CRT.
Most boggleboxes or monitors that I've seen in recent times, when the line o/p transformer goes, it takes the driver transistor with it anyway.
Bloody designers these days use components that are only just capable of doing the job, unlike way back then, when it was easy to over-rate as there wasn't such a wide choice of parts or ability to get new spec. parts made.
I just binned a mint Dell(?) 19" monitor that was Philips-based: one particular IC kept going thermal on me and it was never released for aftermarket. It seems Philips realised they'd arsed-up and did an IC redesign, the new IC isn't compatible
. Lovely picture, shame to bin it really.
Bloody designers these days use components that are only just capable of doing the job, unlike way back then, when it was easy to over-rate as there wasn't such a wide choice of parts or ability to get new spec. parts made.
I just binned a mint Dell(?) 19" monitor that was Philips-based: one particular IC kept going thermal on me and it was never released for aftermarket. It seems Philips realised they'd arsed-up and did an IC redesign, the new IC isn't compatible
. Lovely picture, shame to bin it really.
...I do not zink so........ wedg1e said:
Most boggleboxes or monitors that I've seen in recent times, when the line o/p transformer goes, it takes the driver transistor with it anyway.
Bloody designers these days use components that are only just capable of doing the job, unlike way back then, when it was easy to over-rate as there wasn't such a wide choice of parts or ability to get new spec. parts made.
Shitty soldering and failure to allow for thermal stresses has a lot to answer for as well.
I remember repairing a lot of Samsung ("Korean for disposable") CQA4147 monitors, or possibly firestarters. The main fault was that the E-W modulation transistor was too rigidly mounted on its heatsink, and after a while thermal expansion in its legs cracked the solder off the PCB pads and created an intermittent connection. If the user stopped using it as soon as the picture went wonky, it might be OK. But if not, it could take out the line output transistor, which took out the rectifier diode in that section of the PSU, which removed the feedback to the voltage regulation, so the PSU then wound itself up full pelt and overvolted the entire circuit board, which gained big black charring marks along all the power rails.
Pigeon said:
I remember repairing a lot of Samsung ("Korean for disposable") CQA4147 monitors, or possibly firestarters. The main fault was that the E-W modulation transistor was too rigidly mounted on its heatsink, and after a while thermal expansion in its legs cracked the solder off the PCB pads and created an intermittent connection. If the user stopped using it as soon as the picture went wonky, it might be OK. But if not, it could take out the line output transistor, which took out the rectifier diode in that section of the PSU, which removed the feedback to the voltage regulation, so the PSU then wound itself up full pelt and overvolted the entire circuit board, which gained big black charring marks along all the power rails.
Couldn`t agree more. Or would if I understood a far king word.
Do they still publish the "stock faults" for each model like they did: "when I were a lad" with component mods to cure it?
There were the "trade" publications and then the Red hard backed year books, Er, "Radio and TV Servicing - 1975" etc (I think), that you could find in the Ref. Library.
Are they still Published?........Anyone?
Albeit, I know that IC's have really taken over and "discrete" components are now:.........few. (In other words, there's not much inside folks), just change the offending "board".
>> Edited by 8Pack on Saturday 16th April 05:20
There were the "trade" publications and then the Red hard backed year books, Er, "Radio and TV Servicing - 1975" etc (I think), that you could find in the Ref. Library.
Are they still Published?........Anyone?
Albeit, I know that IC's have really taken over and "discrete" components are now:.........few. (In other words, there's not much inside folks), just change the offending "board".
>> Edited by 8Pack on Saturday 16th April 05:20
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