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Technical Topics => Equipment => Topic started by: flexoman61 on January 11, 2017, 1825 UTC

Title: Longwire antenna
Post by: flexoman61 on January 11, 2017, 1825 UTC
I want to extend my 100' longwire to 200' to help on LW.
With the limited space on my property I will have to go
out 100' then a sharp 90 degree angle out another 100'.

Will the sharp angle be a problem or should I keep it at 100'?

Reading up on this a lot of people insist a longwire MUST be straight,
even for receive only.

I think it won't matter much and will improve my LW reception.

Anyone have a longwire set up like this?

Thanks
 
Title: Re: Longwire antenna
Post by: ChrisSmolinski on January 11, 2017, 1916 UTC
Yes, I have a random wire antenna that I use with the radios in the basement workshop that is oriented exactly like that, and even about those lengths. It works fine, especially once I put a choke (a dozen turns of coax wrapped around a ferrite toroid) on the incoming feed line, to reduce RFI currents flowing on the coax shield. One might make the argument that it is more omnidirectional than a straight longwire antenna.
Title: Re: Longwire antenna
Post by: refmo on January 11, 2017, 2205 UTC
The bend will actually make the antenna more omni-directional at LW thru HF frequencies. (although at LW it would likely be omni-directional with or without the bend).
Longwave performance will see a definite improvement compared to the shorter length.
Title: Re: Longwire antenna
Post by: Looking-Glass on January 12, 2017, 0813 UTC
I run 310 feet of wire here in a "U" shape owing to the dimensions of the land I occupy, it works great, have had exceptional results on LW with JJY Time Signal in Japan on 60KHz last March for over 8,000kms.

On the down side, it tends to raise the noise level but I am willing to accept it.  The more wire the better for NDB chasing on LW... ;D