If it really is too short, stop cutting !!!
chet
----- Original Message -----
From: "D. Scott MacKenzie" <kb0fhp@comcast.net>
To: "Dale Martin" <kg5u@hal-pc.org>; <towertalk@contesting.com>
Sent: December 09, 2006 3:42 PM
Subject: Re: [TowerTalk] 160m inverted l
>I keep cutting and cutting - and it is still too short
>
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com]On Behalf Of Dale Martin
> Sent: Saturday, December 09, 2006 3:05 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] 160m inverted l
>
>
>
> If you've got an antenna analyzer like the MFJ-359, you can see where the
> SWR is minimum. Cut off a few inches of antenna. See where the new
> minimum
> SWR point is. Then you can figure how many kHz per inch the minimum SWR
> point will move with each subsequent cut.
>
> For instance, cut off 6 inches of antenna and find the minimum SWR moves
> from 1818 to 1824. So, the kHz per inch is 1 kHz per inch. If you take
> off
> six more inches, the minimum SWR moves to 1830, or 10 inches to move to
> 1834, etc.
>
> Of course, it pays to be conservative when your are cutting wires, so
> always
> cut for a lower frequency than the actual target until you get with a
> couple
> of inches.
>
> For my 1/4-wave half-sloper on 80, instead of cutting the wire to move it
> into the phone band, I simply bring the antenna end back on itself to
> shorten the overall antenna. I use the same method of calculating how
> much
> will move how far, but without cutting the wire. :-)
>
> 73,
> Dale, kg5u
>
>
>>
>> > John:
>> >
>> > Start out with about 130 feet of wire and trim about
>> six inches at a
>> > time until you get the min SWR where you want it in the
>> band, usually
>> > around
>> > 1830 kHz or so. You should end up with something around
>> 123 feet of
>> > length
>> > but that depends on the usual antenna things like
>> everything else that's
>> > around the antenna, etc. .
>> >
>> > 73 de
>> > Gene Smar AD3F
>> >
>> >
>> > ----- Original Message -----
>> > From: <ny6dx@aim.com>
>> > To: <towertalk@contesting.com>
>> > Sent: Friday, December 08, 2006 9:27 AM
>> > Subject: [TowerTalk] 160m inverted l
>> >
>> >
>> >> I am trying to figure the length of inverted l using #12
>> insulated wire.
>> >> I
>> >> come up with 120 ft is this right?
>> >>
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