View previous topic :: View next topic |
Author |
Message |
vioviovio
Joined: 06 Feb 2006 Posts: 3
|
Posted: Mon Feb 13, 2006 6:58 pm Post subject: Grundig ST-70 574 SAT--CUC 5820 |
|
|
I make a post a week ago about a thermic problem, problem who now it is turn out to be a total failure of TV-set.
First symptom occure a year ago: high level of brightness and an intense white image of a program produced geometrical deformation of picture( a shape like an S of the vertical edges). I decreased the values of brightness and contrast to obtain a corect picture.
6 months later, the problem got worse: if the room temperature was above 25 Celsius, the image on the screen start flickering( a very intense white line flashing on the screen, like a stroboscope). In order to eliminate this annoying efect, i decreased even more the levels of brightness and contrast, or/and opened the room window to lower the room temperature.
Finally, about 2 days ago the image started to disappear and reappear almost immediate until it was gone for good ; the remote and local controls are working and the sound is still OK, except some times is noisy- like a tunner off line.
A visual exame revealed the isolation of the high voltage focus cable was burned ( i dont know if compromised) because it was touching the radiator of the vertical amplifier.
Some multimeter data: power supply is OK( +A=161V; +G=26V; +B=12V; +E=8V; +H=5V) but the voltage recover from the final transf is null( +C= 0 V --corect is 200V). Also, it is not any high voltage and the tube filament it is not on.
The circuit who deliver +C voltage for final RGB amplifier is OK( R528, C529, D529, C527), the BU508A and its circuit is OK, other electrolytic capacitors from the frame stage are OK.
Should i change the starter TDA8140 or should i'll be looking in another place?
If you have any ideea, please, let me know. I only have a multimeter. |
|
Back to top |
|
|
vioviovio
Joined: 06 Feb 2006 Posts: 3
|
Posted: Wed Feb 15, 2006 11:53 pm Post subject: Grundig |
|
|
Problem solved: TDA 8410 .
|
|
Back to top |
|
|
|
|
|
You can post new topics in this forum You can reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
eServiceInfo on FB -
Service Manuals Free Download -
Service Diagrams
Free TV Schematics Download -
HARDW.net -
Pinout Master -
Jabse Service Manual Search -
Jabse.InK -
onTap.bg
SnimkiOt.com -
Poblizo.com : пътешествия
Latest Service Manuals :
[snap-in] RTB Series Richey • Panel CMO N170C2-L01 1 [DS] . Various • KM1530 2030 C-Errors Kyocera • GA34-0851-0 4956 Processor Model K00 Des • Panel IDTech IAUX14K 0 [DS] . Various • RRV4594 - VSX-830-K,VSX-45,VSX-830-S Pio • DCR-TRV738E-TRV740E-TRV840-L3 Sony • SW105, SW205 Pioneer • NHM5-024 NOKIA • 22gr804 Philips •
|