I didn't think that extension was available any more, not sure. One
thing is that that doesn't change the ground side. This extension is
hot, it is part of the hot side of the antenna. What it does do is
give you more radiation surface in the high current region below the
coil.
73
Butch
WA0VJR
Node 3148
Wallace, ks.
On Mon, 15 Aug 2011, Gerry Leary wrote:
> Well you can buy a 2 foot extension for the bottom of the screwdriver if it
> is a high sierra, and that will change the ground side or the feed side of
> the antenna. It will change the way you tune. The other thing you could do
> is to get a section of very heavy PVC pipe and raise it that way.
> ----- Original Message -----
> From: "John Miller" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Monday, August 15, 2011 11:48 AM
> Subject: Re: Need suggestions for better mast arrangement to safely raise HF
> screw-driver antenna on RV
>
>
>> telescopic would be best I'd say though also you need something conductive
>> because it needs the vehicle ground. If you have something nonconductive
>> right now, that's your problem.
>> ----- Original Message -----
>> From: "Tom Behler" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Monday, August 15, 2011 10:00 AM
>> Subject: Need suggestions for better mast arrangement to safely raise HF
>> screw-driver antenna on RV
>>
>>
>>> Hi, all.
>>>
>>> Well, I attempted to check into yesterday's 20-meter Cross-Country blind
>>> ops
>>> net from the RV, but was not successful.
>>>
>>> I believe my screw-driver antenna simply is not high enough on the back
>>> of
>>> the RV to allow me to get out well.
>>>
>>> The antenna is mounted with u-bolts on the back bumpber on a piece of
>>> pipe
>>> that is probably about thre or four feet high. This gets part of the
>>> screwdriver antenna and whip above the roof line of the RV, but it does
>>> not
>>> get it completely above the roof line by any means. The RV is
>>> approximately
>>> 12 feet high.
>>>
>>> Originally, I had used an arrangement with a longer piece of mounting
>>> pipe,
>>> but it turns out that the pipe was de-tuning the antenna, especially on
>>> 10
>>> and 15 meters.
>>>
>>> So, my question is this: Does anyone know of a fiber-glass or other type
>>> of
>>> non-conductive mast that I might try to get the screw-driver up higher?
>>> Obviously, I want to be safe here, and don't want to have to mess with
>>> guys.
>>>
>>> Something telescopic might be the best, but again, I would think it would
>>> have to be of fairly high quality.
>>>
>>> If anyone has any suggestions, I'll save them for future reference.
>>>
>>> Due to a number of other things going on right now that will put a crimp
>>> in
>>> the budget, I probably won't be able to do anything until next year's
>>> camping season, but it's always good to start thinking and planning in
>>> advance.
>>>
>>> 73 from Tom Behler: KB8TYJ
>
>
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