How to best choke a receiver feedline

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I'm installing an active antenna.
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  The seller discusses choking the feedline to prevent it
from adding signal.
  How do I best accomplish this.
I don't have any beads, I do have loads if ferrite potcores and some  
toroids.
  The antenna will be up 24ft, last 4 feet is pvc, the first 20 ft is  
steel.
Will it help to run the coax inside the mast?
About 75 ft of the coax is run underground and then about 7 feet up to  
the radio.
  I plan to choke it at both ends.

                             Mikek

Re: How to best choke a receiver feedline

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This is no antenna, it is a joke, a bad joke.

w.

Re: How to best choke a receiver feedline
On 11/16/2017 1:36 AM, Helmut Wabnig wrote:
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  Hmm, everyone has an opinion, is yours based on testing one?

Anyway, I found my problem was not the feedline. I started turning off  
breakers and one of them shut down the buzz. Two sources of buzz were on  
that breaker and outdoor light with IR sensor and my garage door opener.
I had a very minor buzz left, audible but didn't show up on the S meter.
That was cleared with an isolation transformer and lifting the ground wire.
  Now I can receive 200kHz beacons, AMBCB, 80 meters, 40 meters 10  
meters and 28 MHz CBer's. So it works, do I have anything to compare it  
to, not yet, but I'll be putting up a long wire soon.

                                            Mikek

   Btw, the antenna is quiet, without any chokes. I don't know if
running the coax inside the metal mast helped, the mostly underground
feed line probably did. Oh, I just realized I do have a choke at the  
bottom of the mast, just before the feed line goes into the ground. I'll  
remove that tomorrow and see if it's needed.

Re: How to best choke a receiver feedline
On 16/11/2017 07:36, Helmut Wabnig wrote:
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It is a perfectly acceptable active antenna, and works as well as any  
other short active antenna.

The comments about choking the feed-line are quite reasonable, it you  
have an antenna high up in the clear you don't want signals,  
particularly local noise, picked up on the feeder being fed to the receiver.

Jeff

Re: How to best choke a receiver feedline
Jeff wrote on 11/16/2017 5:16 AM:
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An acceptable choke can be a coil made of the feedline coax, correct?  My  
understanding is you have to match any magnetic material to the frequency in  
use while an air core doesn't have that complication.

--  

Rick C

Viewed the eclipse at Wintercrest Farms,
on the centerline of totality since 1998

Re: How to best choke a receiver feedline

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Depends on the frequency in question.

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True, but  at lower frequencies it is not possible to get enough  
inductance without a magnetic core of some sore in a reasonable size.

Jef

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