On Nov 26, 4:26*am, b wrote:
I'm trying to fix this European ELBE E12D chassis tv. The inital
problem was this:

http://www.fileden.com/files/2007/6/...3/DSCF8210.JPG

As you can see, there is a venetian blind effect, and considerable
foldover. The voltages around the IC seemed normal. It looked like a
pumpup cap failure, but a change of several caps didn't alter
anything, so I got a new TDA 8178S frame chip. that produced only the
usual horizontal line. A TDA 8170 (which was in the schematic for the
set) also did the same. Re fitting the original brings back the
initial fault.

Is this likely to be a case of requiring the original TDA8178 part or
could there be somethign else I should pursue?
-B

IMO you have some really bad capacitors in that vertical output. An
ESR meter, even a modest one like this

http://www.matelectronics.com/acatal..._Other_61.html

(scroll down to IN CIRCUIT CAPACITANCE TESTER)

will give you good info but keep in mind some models have large values
(1000uF) in the feedback loop. Even a very mild deterioration can
cause significant linearity issues. The tester _will_ show it as not
as good as a new one but still seems OK. Don't be fooled.

G²