Dick:

DS I have a large screen Sony TV connected to a satellite receiver. One TV
DS output goes to the VCR and the VCR audio output goes to a small stereo
DS system. It has worked fine until recently. A slight herringbone pattern
DS develops when the stereo system is turned on, whether watching a tape or
DS watching live TV through the VCR.. It vanishes if you turn off the stereo.

As the others indicated, first check for proper grounding and
shielding. Use good-quality cable: generally the smaller the diameter
of the coax the less shielding it will offer. (Compare RG-8/U to
RG-58/U.)

Another potential problem is the IF (intermediate frequency) stages of
your receiver(s). IIRC the IF for FM is 10.7 MHz. This means the FM
receiver can create a signal which is in the TV band. Is is possible
for the signal to travel through the center conductor so the best
grounding and shielding in the world won't remove the herringbone.

You've done part of the testing: when the stereo receiver is on you
notice interference and when off it's gone. Now for a couple other
tests. Does changing the (FM) station remove the interference? If it
does that pretty much points to IF leakage. Is it possible to move
the stereo? I have an integrated receiver on a shelf above my
monitor. The power transformer (or power supply) causes a slight
wiggling of the image on the CRT in the upper left. As it would be
inconvenient to move things around I put up with it, just move the
display so the section I'm working on/viewing isn't at upper left.

-
¯ barry.martinþATþthesafebbs.zeppole.com ®

* I suppose there's some sort of poetic justice to this. If so, it eludes me.
---
þ RoseReader 2.52á P003186
þ The Safe BBS þ Bettendorf, IA 563-359-1971
---
þ RIMEGate(tm)/RGXMod V1.13 at BBSWORLD *

Nearly always the cause is bad connectors. The ones that "screw" onto the
coax are especially prone to failing. Even the good ones that require the
$30 cruncher tool to put on can fail, but it's much less likely. Of course,
you simply can't use the cheapo Radio Shack coax with the aluminum foil
shield. I find the RG-6/U (hearvy duty shield) to be best and Home Depot
sells it buy the foot.


"barry martin" wrote in message
news:1050627797.0781.05.9763350.1925701445.RIMEGat ...
Dick:

DS I have a large screen Sony TV connected to a satellite receiver. One
TV
DS output goes to the VCR and the VCR audio output goes to a small stereo
DS system. It has worked fine until recently. A slight herringbone
pattern
DS develops when the stereo system is turned on, whether watching a tape
or
DS watching live TV through the VCR.. It vanishes if you turn off the
stereo.

As the others indicated, first check for proper grounding and
shielding. Use good-quality cable: generally the smaller the diameter
of the coax the less shielding it will offer. (Compare RG-8/U to
RG-58/U.)

Another potential problem is the IF (intermediate frequency) stages of
your receiver(s). IIRC the IF for FM is 10.7 MHz. This means the FM
receiver can create a signal which is in the TV band. Is is possible
for the signal to travel through the center conductor so the best
grounding and shielding in the world won't remove the herringbone.

You've done part of the testing: when the stereo receiver is on you
notice interference and when off it's gone. Now for a couple other
tests. Does changing the (FM) station remove the interference? If it
does that pretty much points to IF leakage. Is it possible to move
the stereo? I have an integrated receiver on a shelf above my
monitor. The power transformer (or power supply) causes a slight
wiggling of the image on the CRT in the upper left. As it would be
inconvenient to move things around I put up with it, just move the
display so the section I'm working on/viewing isn't at upper left.

-
¯ barry.martinþATþthesafebbs.zeppole.com ®

* I suppose there's some sort of poetic justice to this. If so, it eludes
me.
---
þ RoseReader 2.52á P003186
þ The Safe BBS þ Bettendorf, IA 563-359-1971
---
þ RIMEGate(tm)/RGXMod V1.13 at BBSWORLD *