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Twin Lead and metal mast?

Oct 31st 2014, 16:12

KO0Y

Joined: Apr 7th 2012, 19:22
Total Topics: 0
Total Posts: 0
I bought a dozen of those army surplus four foot aluminum poles and plan to use them to hold up the center feed point of a long non-resonant dipole (260'). Well, it might be more of an inverted v since the ends will be 20-25' off the ground, and the center twice that.

I will use 300 ohm twin lead for the feed line back to a balun in the shack. I know that the feed line should leave the dipole at a right angle. My question is whether I can run the line down the mast, or if it needs to run away at a right angle to both the antenna and the mast? Thanks for advice.
Oct 31st 2014, 21:27

AA6E

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
It can run parallel to the mast, but you need to hold it several inches away using standoffs. (My estimate is at least 10 X the twinlead conductor spacing.) If it's too close, the mast will affect the impedance of the twinlead and possibly cause current imbalance.

73 Martin AA6E

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