> Here is the problem. TV on second floor. Tower is about 5 feet away, on the
> other side of the wall. I have had TVI issues with this TV (Sylvania 32 inch
> color) on HF but have tamed it with toroids on the cable lead in and the
> power
> cord. Even with the KW.
>
> On 50 mhz, with my 5 element yagi 30-50 feet above the TV, and the roof,
> depending on how high I have it cranked up, I take the TV sound (primary) and
> picture (not so critical) out with 2 watts. This happens when the antenna is
> pointed directly over the house. When the antenna is at right angles to the
> house,
> no TVI, even with 100 watts. This is on all channels and with cable TV. I
> have
> had new cable run, quad shield, with no improvement.
>
> I have added all kinds of toroids to both AC line and the cable with only
> slight improvement. There is a seamless aluminum rain gutter, 30 feet long,
> running along the roof a few feet above the TV. In the same direction as the
> TVI.
> Grounding it has not helped.
While we have all discovered common-mode ingress (which is what toroids on line
cords and cable fix), don't forget good ole differential-mode ingress. Insert
even a dumb old Radio Shack High-pass filter in-line with the coax. Just fixed
my own TVI at my new vacation house that way.
Radio Shack does not appear to carry such filters nowadays (I had a few old
ones left over), but cable TV shops like Coast CATV Equipment Supply, Inc. in
Corona, CA 92880 Tel: (800) 800-2770 appear to carry suitable filters. Check
out http://www.coastcatvsupply.com/Pico/picomacom.htm
GL and 73,
Doug K1DG
_______________________________________________
RFI mailing list
RFI@contesting.com
http://lists.contesting.com/mailman/listinfo/rfi
|