Let me take a stab at this. Due to the fact that your TVI is on all
channels everywhere in your house, a lot of causes are rulled out. It
probable doesn't have anything to do with the fact you changed
feedlines. As others have said, the balanced line should work fine. I
would say that most likely the source of your problem is either:
1. A loose connection, or broken wire, in your feedline. Could be
anywhere along the line but most probably at the connection to the antenna.
2. Your cheap VCR
3. A loose cable connection to a cheap VCR.
Number 1, broken wire, can turn your dipole into something that looks
like a vertical with ground return currents through your house wiring.
The easiest way to determine this is to drop the antenna and get out the
ohmmeter.
Number 2, cheap VCR, is usually never suspected. Many of these VCRs put
a diode across the antenna terminals. I guess they figure they are
protecting the antenna inputs. This serves as a great rectifier, which
generates tremendous quantities of harmonics, then applies this into
your cable system, which goes all over your house.
You can test for this by unplugging all the stuff connected to you cable
system, then one by one, add them back and see if you can find a
culprit. Usually the problem is created by RF overload. If this is the
case, put several ferrite beads on the input cable to the TV/VCR
equipment which is causing the problem. You may also have to put some
on the AC line as well.
Number 3 is obvious. This allows common mode signals into the VCR which
rectifies them, and the rest is the same as #2.
Jerry, K4SAV
Buck - N4PGW wrote:
>I had a 129 foot dipole fed with CATV coax. It did ok, but where the
>aluminum met the copper, it oxidized and I have been suffering with AM
>broadcast band bleedover on all frequencies below 14 MHz. I recently
>replaced it with a 135 foot dipole fed by 300 ohm TV twinlead to my tuner on
>which my IC-706 sits. The problem I have now is TVI. When I get the
>antenna tuned and run more than 30 watts, the TV pictures turn red, green,
>or blue. We are on Cable TV and I cannot recall the last time I had TVI
>other than when I operated 6 meters and the rig is sitting less than two
>feet from my TV. (the TVI now is all over the house.) I don't know if it
>is getting into neighbors homes at this time.
>
>I figure I am getting less loss tuning that antenna with twinlead as opposed
>to coax, but I have a piece of RG-8 foam I am thinking about feeding the
>antenna with instead.
>
>Any suggestions or ideas?
>
>thanks,
>Buck
>N4PGW
>
>
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>questions and ask for Sherman, W2FLA.
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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