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ml · December 30th 08, 12:22 PM posted to rec.radio.amateur.antenna

In article ,
(Richard Harrison) wrote:

ML wrote:
"----seems like I am giving a lot of TVI on strangely enough 2m."

Probably receiving amplifier overload.

Antennas usually couple more tightly side by side than they do end to
end where they reside in each other`s nulls. If the TV antenna is
horizintally polarized while your transmitting antenna is vertically
polarized. that should greatly decrease coupling between the antennas.
Maybe distance between the two antennas can be maximized. Maybe the new
TV antenna has a feedline defect allowing the line to become part of the
receiving antenna. Its coax should prevent noise pickup not cause it.
Maybe careful adjusting cross-polarization of the antennas, or a
combination of cures will fix your problem. I hope you are lucky.

Best regards, Richard Harrison, KB5WZI

big thanks to all those that replied

I agree it is prob 'overload' but thought perhaps notching might
work, i already have some really good multistage tvi filters but
wanted to be ready with a notch for when the building lets me into
the closet in case that is not enough.

My thought was to try and make stubs cause they are 'cheep' but
those links to the commercial site were pretty cool

wasn't sure the difference between the single stop unit and the one
with 2 stops (past the obvious)

my thoughts would be that either wont effect the other
frequencies as a stub might (2nd 3rd harmonic?)

Currently have 2 2m antennas Rich, once is a arrow 2/440 jpole
and it is about middle of the antenna towards it's left side
about 2 ft or so away

directly in front of it is a M2 eggbeater rather omni pattern

it's about 3-4ft away so the tv antenna is looking right at it

I don't really have any place to move the antennas to other than
some sort of compramise like moving the antenna towards the floor
wich then the elevator room would block me in at least 1 compas
direction and losing the altitude would of course loose me the
distant repeaters using one of those floor mounts which i already
have actually

question
perhaps putting the 2m antenna higher than the tvi antenna might do
the trick ? the jpole has no radials the eggbeater does so i am
guessing the eggbeater might offer less downward radation? and
therefore offer less tvi if higher than the tv ant?

thanks