Sounds like it's just determined to have problems but you're not out of bandaids just yet
So today (Christmas day) I can report the following.
1/ The screen blacks out about once a week, not too annoying to us we just turn it off then on again.
2/ I have also noticed it sometimes blacks out then comes back on a second later by its own accord. That's not in line with the previous findings of the cause being FAULT triggered since that needs a power cycle to reset it.
3/ We just noticed today a single thin vertical line from top to bottom has appeared smack bang in the centre of the screen....Oh wonderful !!!
Last edited by loopyloo; 25-12-17 at 07:23 PM.
Sounds like it's just determined to have problems but you're not out of bandaids just yet
loopyloo (05-04-18)
TV hasn't blanked out for a long time now so I guess that's not really a problem anymore.
but work this one out :
A few weeks ago a single very thin vertical line appeared in the centre of the screen. it didn't really bother us because it was quite faint and only visible on a light coloured screen. I know often these lines are caused by bad connection with the screen pcb or cable but found it interesting that this caught my attention when there was something symmetrical displayed on the screen and this line appeared to be in the middle. i got out my tape and measured it. Exactly in the middle of the screen....hmmm !
Then two days ago the line disappeared and a new vertical line appeared 80mm to the right of where the first one was....hmmm !
Tonight, suddenly no lines at all .... say what ?
I wonder if there's a ghost inside this tele.
Sounds like it's providing more entertainment than originally intended
Does thumping it make any difference? (gently and without using a brick)
loopyloo (05-08-18)
Ha ha no it doesn't. I've already tried that. Also squeezing the top of the screen (gently).
I thought the line that first appeared was a bit strange because as you know, vertical lines tend to be placed randomly (if it's a faulty screen or cable). This one was exactly to the millimeter in the centre. That made me wonder if it could be a board thing or even a software glitch.
The lines haven't returned at this stage, just a perfect picture.
Back again ha ha.
The big fella started playing up again this morning.
This time it's back to the screen backlights not wanting to play the game.
When powered up, I get about a quarter of a second to view the Changhong splash then out go the backlights.
Looks like it's gotta move back to the workbench for another look.
The fun just never ends with this one
Considering the current level of reliability I'd be revisiting the PFC circuit problem to see if it could be revived (well maybe).
Quite a few repairers would be sizing it up for a boat mooring by now too.
loopyloo (05-08-18)
So from my last post 01/08/18, I attempted to start it heaps of times that morning which included total power off several times but it wouldn't go any further than that quick flash of the splash.
At 1:30p I gave it another shot and it started up and hasn't given any problems since.
Wed morning was pretty cold so might be somehow temp related.
Ha ha, Def don't want to go back to the PFC.
Skepticist (04-08-18)
dunno if its relavent but I had a new tv akai i think had this type of problem ,recall it turned out to be a tant cap cheers
loopyloo (05-08-18)
For your enjoyment - another update.
The TV has been behaving for a while now but today I saw this :
We have a very sick doggie at the moment. She spewed on the floor in the loungeroom, so the wife got the carpet cleaner out, you know, one of those Bissel upright carpet cleaners.
The instant it was turned on, the TV went black.
I got her to try that again, several times in fact, and the TV backlights went out each time.
How interesting !
This thread has been running for fifteen (15) months now.
Perhaps it's time for a change of subject?
Silly boy that I am, I have only just now realised....
It's for the Guinness Book of Records!
loopyloo (10-10-18)
Hmmm my guess is it's super sensitive to a dip in voltage that it would normally compensate for if the PFC was operating. Any other large appliances should produce the same effect in that case EG welder, pump etc
If you can, maybe try running the TV on a different circuit to the appliances with large starting currents to eliminate the possibility of the majority of the voltage 'flicker' being in the home wiring from the main switchboard. The distance of your electricity service from the distribution transformer will also come into it but to a lesser degree normally due to heavier conductors in the street (usually rated at 400A in most cases, 250A in some circumstances where the customer density is lower than typical suburban layouts)
Yep it's sensitive to power dips alright.
Dist transformer right out the front of my place. lol.
Not able to power from other house circuits (unless I run a lead to downstairs).
I'm also thinking about those PS caps I changed in the beginning. or maybe I need a box with a couple of big caps inside to plug it into. Hmmmm, what have I got in the shed ?
Banned
Haven't had an update on this for a long time now
Still working?
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