Hasan,
There is a design done by Jeff Briggs derived from the Battle Creek Special
that you could adapt. He called it the "BC Trapper" and I'm sure you can
google it. It's a 40-80-160 with top-loading. He uses pieces 4 or 5 inch
PVC sewer-pipe as coil forms, makes coil/capacitors from coax, then goes
nuts with electrical tape. I've been happy with mine. You might leave out
the 40M trap and use that.
Rex - K1HI
Rex Lint, Consultant
26 Brek Dr.
Merrimack, NH 03054
PH: 603-860-7651 FAX: 603-882-6612
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of hasan schiers
Sent: Friday, October 07, 2005 4:00 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Trapping my 80m Inverted L for 160?
I'm having great success with my 80m inverted L (45' up and 25 or so feet
out), with 26 radials (now). (Hung off the side of my tower)
I had a thought for something to just "get me on" 160. Is there any reason I
couldn't put an 80m trap (design freq, please?) at the end of the 80m
horizontal wire and stretch it out for 160? I read the article on W8JI's
site
about coaxial vs other traps. Since I'm not going for broke, but just want a
quick and dirty solution, I was thinking about making a coaxial trap for 80m
out of RG8/X coax (or I could buy some 58a/u) that I have laying around. Not
running more than 500w, so this size coax should be fine.
My questions:
1. What freq should I "design" the trap for?
1a. The program referred to on your web site (trap design) has no entry for
8x, but manual values can be entered. Anyone have ready access to the parms
for 8x that I
need to enter?
2. I assume the trap will detune the 80m section, making it longer. Any
ideas for a starting point on how much to shorten it, or should I just cut
and try?
3. Will there be any degradation on performance on 80m from adding the trap
and wire extension to enable 160m?
4. Any suggested starting wire length after the trap to resonate 160
towards the lower (DX) part of the band?
I don't want to ruin the excellent performance I'm getting on 80m, no matter
what I do, so if I can't do this without compromising 80m, I'll think about
another alternative.
Thanks for any ideas you may have. I wan't to get this done before the snow
flies!
73,
...hasan, N0AN
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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