[RFI] 6M Getting into TV Channel 3 - CLARIFIED!

Jimk8mr at aol.com Jimk8mr at aol.com
Thu Jul 3 11:33:26 EDT 2008


 
It sounds like basic RF overload of that preamp.  Does the  interference 
arise when transmitting on other bands?  Are antennas for  other bands as close to 
the TV antenna/preamp?
 
First I'd try some ferrite on all the leads to the preamp - input, output,  
power (if not fed up the feedline). Several turns or more around each ferrite  
torroid.
 
You might also try some common mode suppression, in the form of two 300 ohm  
twinlead to coax transformers connected back to back. 
 
 
 
Good luck,
 
Jim   K8MR
 
 
In a message dated 7/3/2008 11:23:32 A.M. Eastern Standard Time,  
doc at kd4e.com writes:

Lots of  great assistance already, thanks!

Here are some additional  clarifications ...

1.  The interference is on all TV channels, VHF  & UHF.

2.  Removing the distribution amp eliminates both  my
desirable TV signal and the 6M  interference.

3.  I presume that my Yaesu FT-857D is not  sending
TV frequency signals to my homebrew delta  loop
so it must be that the distribution amp is  picking
up 6M along with the weaker TV signals and  amplifying
them all together.

Therefore, I am  guessing that I need a 6M trap filter
just prior to the TV distribution  amp. so it has nothing
on 6M to amplify.

Where do I find such a  critter?  Or are they fairly
simple to build?

WDAYT?   (What Do All Y'all Think?)

:-)

> I raised my delta loop  *from* a feedpoint of 6'
> above the ground *to* 15' and now it is  getting
> into the TV (all channels).
> 
> The TV antenna is  at 30 feet and is about 30'
> from my 6M antenna.  (I am running  100W SSB.)
> 
> I have disconnected the outside antenna at  the
> distribution amp inside the house and used an
> amplified  set-top antenna - no interference then.
> 







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