Maker Pro
Maker Pro

Sony 36" TV weird problems.

D

Dani

Jan 1, 1970
0
Model # KV36FV15. Unit has no raster, or audio, has a low "white
noise" in the speakers, but has filiaments, & 30 KV high voltage. Turn
up G 2 gives no vertical, not quite enough horizontal
width, sometimes the lower half of the picture has raster, & retrace
lines, & bad pincushion correction. I removed the rear vertically
mounted A/V board, looking for bad connections, as it is
a common fault. B + is 135 volts, & I have 22, -15, & 15 volts. The
front buttons don't work, but
unit comes on with a remote. Even with the remote, I can't get input
access, or select vloume, channel etc. Led flashes continuously, no
code.I read somewhere something about the data & clock lines, but it's
really a stumper. Anyone see this very odd problem before? Thanks,
Dani.
 
C

Colin

Jan 1, 1970
0
One voltage you haven't mentioned is 5 volts. There is a good chance this is
not reaching certain places that it should. If this is missing it will also
upset the clock/data operation.

Assuming all is ok with the above,
Scope the field ramp waveform and if correct check the DC conditions around
the field output stage. If all correct try changing the field output IC.
If the ramp waveform is not right you need to investigate around the
timebase generator.
 
One voltage you haven't mentioned is 5 volts. There is a good chance this is
not reaching certain places that it should. If this is missing it will also
upset the clock/data operation.

Assuming all is ok with the above,
Scope the field ramp waveform and if correct check the DC conditions around
the field output stage. If all correct try changing the field output IC.
If the ramp waveform is not right you need to investigate around the
timebase generator.

I have seen these symtoms caused by a bad IC that contained the
blanking circuits,video etc,it also
had some bad filters connected to it
 
Top