Two Horizontal Dipoles facing different directions on a switch

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Super60
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Two Horizontal Dipoles facing different directions on a switch

#408984

Post by Super60 »

Gentlemen hello,

I have a question concerning a possible setup for my base. At present I am running a horizontal dipole radiating SW/NE or the ends are pointing NW/SE. For my location [not ideal with many trees and down a hill a bit] I have had good luck. From the state of MA I hit TX,AZ,CA etc. Definitely SW from me. NE I have hit England and Germany when conditions allow. I would like to also transmit and receive more from the NW and SE. I sometimes hear them but rarely contact them. I am pondering the possibility of another dipole on a switch that would radiate/receive from the NW/SE. My question is can I put another dipole suspended above or below the other to make an + that I could switch from one to the other to pull in a signal that is not receiving or transmitting well on the other dipole? Kinda like a poor man's beam antenna?
I would obviously be only using one antenna at a time. Would there be bad interactions between the two antennas and would performance suffer? If so how far would I have to mount the antennas away from each other? Any thoughts would be great. 73's

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MDYoungblood
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#408987

Post by MDYoungblood »

IMO, the two will interact with each other but not in a bad way. If they are true half wave dipole, the feedpoint is roughly 300 ohms, adding the second dipole to the same feed point should drop it to around 150 ohms and then it would basically be omni-directional. Now if they are inverted-V dipoles, you are using the dropped ends to match impedance, 50 ohms, I would use 75 ohm coax and make a co-phase setup. either way it will be a little experimenting to get the needed impedance for the radio.

3's

Greg






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#408990

Post by Super60 »

Thanks MDYoungblood for the reply. When you say add a second dipole to the same feed point are you saying to power both dipoles at the same time? What I was thinking was two runs of coax to two different dipoles aimed in different directions and a switch to use either one or the other only. Would that work?? Please excuse my lack of knowledge here.







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#408991

Post by MDYoungblood »

Using a switch and 2 coax feeds would be fine. Experimenting is the best part of the radio hobby, no need to apologize for answering questions.

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#408993

Post by Super60 »

Thanks much.







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#408994

Post by Blue Ox2 »

It has been suggested to me that perhaps a 19" difference between the two dipoles. One a little bit off the roof, then the second one in the other direction about 19" above it instead of laying right on top of the first one.

Just a thought.

73,

Mike







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#408995

Post by Super60 »

Interesting ,sounds like good advice also. Thanks.







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