Forum > LCD TV forum

Technika 26-207 26"LCDTV-sound no picture*UPDATE* opened unit and found........

(1/2) > >>

markie76:
Hi,

A friend of mine bought a Technika 26-207 26" HD Digital TV described as working but when he got it home and switched it on the blue LED comes on and you can hear sound but there is no picture. The screen is not smashed and it looks like the backlight does come on.

I was wondering if anyone had experience of this brand

or a user/service manual

or can offer advice on this sort of problem.

Thanks,

Mark.

terminator2k2:
hi there, possibly uses the 17mbxx chassis....can you see a faint pic on the lcd screen at all when its switched on.?? is so sounds like the inverter board is at fault and needs replaceing....

tv tony:
if this is the lcd2602 a more likely cause is the diode feeding the 24v line to the inverter, its nearly always dry and as a result gets hot till it eventually goes s\c.
although terminators post is equally plausible, many thanks
tv tony

markie76:
I actually think the inverter is fine because the backlight is firing up - you can see slight light bleed around the edges of the screen. It just looks like no signal is being fed to the screen and it remains just black/blank.

Does the 17mbxx chasis suffer from a signal processing fault?

Thanks,

Mark.

markie76:
We've taken it apart and found some interesting things. The main PCB: 17MB12, PSU board: 17PW22-4.

On the PSU board there has been some work done.

1. Some tracks have been repaired.
2. PL808 has a solder ball on the copper side but no socket topside. PL807 is empty also but it looks like thats how it left the factory.
3. 10uf 50v capacitor soldered between PL806? & PL822 on the underside.





The other most suspicious change is the cable which goes from the main PCB to the LCD panel looks like it has had some sort of Frankenstein job done on it - where it has been 'chopped' and resoldered at the main PCB end. However, some of the wires from the cable have large crimps on them which are just taped up. To me it looks like a cable from another unit (but fits the socket on the LCD panel) has been attempted to be adapted for the plug to this main PCB. See pics below.

 

Would any of you guys with experience of the 17mbxx chassis seen this done before or can think why this would be done?

As the tv powers up and processes sound (just blank screen) my starting point would be to get a new PCB to LCD cable.

The panel in this tv is a Samsung -

Any help much appreciated.

Thanks,

Mark.

Navigation

[0] Message Index

[#] Next page