View Single Post
  #5   Report Post  
Posted to sci.electronics.repair
Arfa Daily Arfa Daily is offline
external usenet poster
 
Posts: 6,772
Default Digital sat receiver colour problem


"David Sewell" wrote in message
...

"Arfa Daily" wrote in message
...

"David Sewell" wrote in message
...
Hi,
I have a Silvercrest SL65 satellite receiver, the one Lidl's sell

regular,
german origin I believe. When first switched on it is fine, but after a
couple of minutes it will lose the red. Switching off and on will

return
the red but only for another couple of minutes. If the receiver is
left
on
the red come back and stay, and that is the way it been behaving a fair
while now.
I used to repair tv's along while back. But I still have a fair amount

of
test equipment etc. What please could be this problem? I was thinking

is
it
more like quartz crystal playing up?
Help needed and appreciated thank you.

David

There is little in a digital sat box that's serviceable. other than the
power supply, even to service departments that are well equipped and
supported by the manufacturers. I feel that it is unlikely to be a

crystal
based problem losing just one colour. Are you watching composite out, or
RGB ? If RGB, then the problem might be traceable to something in the
red
channel, but even then, you will probably struggle without schematics,
which I doubt are available for a product sold through Lidl's.


If it's not a silly question, if the red eventually comes on and stays
on,
why keep torturing yourself turning it off ... ?

Arfa

Because it may be a long wait ( like watching paint dry, perhaps.). I had
a
look inside and I can see I would stand a much greater chance of diagnosis
with the aid of a manual. The red disappears gradually over about 30
seconds. Switch off, switch on, always get's the red back etc.
I switched over from RGB to CVBS in the menu and that works ok, crap
quality
picture now though.
Thanks,
David


That would indicate that the problem is in the red channel of the RGB drive
circuitry. If the composite remains correct, then the decoding is working
correctly. In the absense of a set of schematics, I think that about the
only way that you might get a result, if you're lucky, is to have a pop at
it with a hair dryer, and a can of freezer.

Arfa