ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hello everyone!
I recently found an Beovision LX5500 at our local flee market and just couldn't resist the looks of it. It's still on it's original stand and in mint condition, just wow..
There's only 1 problem, the image sometimes switches from RGB to grayscale. Does anyone have any pointers to a possible solution? I don't mind diving into the electronics (I'll make sure the caps are all discharged so I don't kill myself).
I actually already had a look in the back and noticed the ingenious build of the frame with all the boards held into place! I was able to disconnect most of the cables to slide out the main board frame but the thing that stopped me was the infrared sensor wiring, which didn't seem removable without destroying it?
Any help would be sincerely appreciated!
Thanks,
Kevin
The colour decoder pcb was rather prone to dry joints in this tv.Sadly,I've just had a ruthless clear out,otherwise I would have had a spare one too!!!
It's the small module that sits in front of the big canned processor/text module.
You can unplug it to investigate.
The chip IC4 (TDA3506)gets quite hot,and it's pins can become dry jointed.Also the tiny surface mount capacitors on the back of the pcb can crack.
Have a good look with a magnifying glass,my guess is that's where the problem is.There are other components of the board that may be dry jointed too of course
Indeed,great telly's,still capable of good results,and plenty of connection options for external digiwotnots.
Nick
Thanks for the valuable intel Nick! I'll have a look tonight.
Any pointers on how to disconnect the IR sensor (on the board side) so I can pull out the entire board unit?
Gr,
All the wiring looms along the front edge of the main pcb are un-plug-able,the small white ones just look as though they don't! You can tug them by the black wires,they are quite tough!Praps take a photo of where they go,although they are cleverly arranged to only fit where they should!
The chassis will slide back some way to give access,but if you want to remove the chassis to the bench for real good look,you will need to disconnect the crt final anode.
Try to avoid this unless you are really well versed in tv work? It can bite!!!!It carries a huge static charge,which you ideally need to discharge first of course!
If in doubt DONT GO THERE!!and simply prop the chassis on a box say,so that you can explore further?
Regards,
Nick!
Aha, excellent. Those little buggers really didn't look unpluggable, looks can be deceiving!
I'll avoid to disconnect the anode and work on a box instead, thanks again!