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W1NK

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« on: February 18, 2004, 08:15:19 PM »

With spring around the corner a ham's fancy turns to antennas.....  

Well in reality, with a baby on the way, thoughts turn to one *last* antenna (for now)...

A little background first:
I currently have an Antennas & More 40M "Windom" up about 20 feet or so.  While it plays well on 40, it definitely isn't doing much on 80 (naturally) except keeping the clouds warm.

Now, according to the mfg, the antenna's dimensions are 45 ft on the long leg and 21 ft on the short.  Not exactly following the calculations for a Windom, I know.  Actually he multiplies antenna length by .68  and .32 for the long and short legs (as opposed to .64 and .36 typically used).  No feedpoint balun is used except for a ferrite balun on the coax.

So I got to thinking about "modifying" it to get it on 80.  Namely adding "tails" hanging down 90 degrees.  More specifically the antenna length would be 130 feet with a 21 ft tail on the short end, now 42 ft long, and a 43 ft tail on the long end, now 88 ft long, (this would have to be bent another 90 deg at the 20 ft level and run parallel to the long leg).  These total lengths follow the mfg's calculations noted above.

Those are my thoughts.  If it really isn't a viable antenna, I'll begin scoping out trees for a better design.

Thanks,
Frank W1NK
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WB2WIK

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« Reply #1 on: February 18, 2004, 08:44:29 PM »

That ought to work to some extent, however remember that when you add "tails" (wire extensions hanging down towards the ground), you need enough antenna height to make them actually functional -- and you certainly need sufficient height so the extensions don't hit the ground, which in your case, it sounds like they would: Unless you substantially raise your antenna height.

I'd add the extensions but do everything possible to raise that antenna a lot higher than twenty feet.  At twenty feet, it's not even a cloud warmer on 80; it's more of an earthworm warmer.

WB2WIK/6
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W1NK

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« Reply #2 on: February 18, 2004, 10:35:43 PM »

So, *that's* why it looks like earthworm Club Med under my dipole :)

I was concerned I may not have figured my "tail length" corrrectly.  Actually, not being able to raise the antenna, would be a worst case scenario.

I should be able to get the thing up about 30-35 feet thanks to an electrician friend with a hefty extension ladder.

Thanks Steve

Frank, W1NK
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