using aerial interactions to get "impossible" nulls

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Tim Bucknall
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Location: Congleton, often in the Peak District, sometimes in Poland or Kresy
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using aerial interactions to get "impossible" nulls

Post by Tim Bucknall » 18 Jun 2016 16:32

John touched on this a while back iirc

i had an interesting experience this afternoon in the Peak district, i was parked less than a mile from sutton common with a valley between us but could Null 96.4 Signal 1 and hear Free Radio from Sutton Coldfield on thecar rx by arranging my mag mounted whips on the car roof at various distances to the car radios whip aerial
i could look out of the window and see Sutton Common while listening to Sutton Coldfield on 96.4!

i couldn't manage to repeat this with any other signals in the short time i had but i see definite potential for freeing up channels on the band for dx
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John J Cahill
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Re: using aerial interactions to get "impossible" nulls

Post by John J Cahill » 18 Jun 2016 19:01

I recall having a Toyota Corina in the 1980s which had the antenna in the front pillar by the drivers door and you could reach out and adjust the length of the antenna, making it shorter for the top end of the band to increase the signal pick up or extending it to its full length for the bottom of the band.

JJ

Tim Bucknall
Posts: 1690
Joined: 01 Oct 2014 14:55
Location: Congleton, often in the Peak District, sometimes in Poland or Kresy
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Re: using aerial interactions to get "impossible" nulls

Post by Tim Bucknall » 18 Jun 2016 19:17

I always forget to do that , I need to stick a big post it note somewhere!
Home:Burkhardt Reuter RDR54D1 SDR V.415,
+ CLP 5130 Log P ant

Mobile: Comm Radio CR-1 + Sharman Skyscan ant, Pira P275

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John Faulkner, Skegness
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Re: using aerial interactions to get "impossible" nulls

Post by John Faulkner, Skegness » 18 Jun 2016 23:21

I do that very thing when I drive to local spots. I have a few lengths of steel rods cut for the bottom, middle and top of the band. It makes a BIG difference.

The antenna on the car unscrews easily. I don't know if yours is the same type Tim, I suspect it's more likely to be than not, but you can get threaded steel bars from B&Q which fit the socket perfectly. They are a metre long and cost a couple of quid each, so it's not expensive to have a few cut to length.

I remember us being parked part way down the hill at Mow Cop, nudging the car backwards and forwards, over and over again, trying to find the sweet spot where Holme Moss gave way to Haverfordwest.

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