| G0FTD > TECH 28.06.08 09:58l 68 Lines 1994 Bytes #999 (0) @ WW
BID : 000241179PZT
Read: GUEST DJ2RR OE7FMI
Subj: Re:160m 7 Ferrite Rod Aerial
Path: DB0FHN<DB0MRW<DB0ERF<DB0FBB<DB0IUZ<DB0OVN<DB0GOS<DB0RES<DK0WUE<7M3TJZ<
ZL2BAU<GB7PZT
Sent: 080628/0636Z @:GB7PZT.#24.GBR.EU [Kidderminster] #:24100 XSERV410h
Date: Sat, 28 Jun 2008 07:36:57 +0000
From: g0ftd@gb7pzt.#24.gbr.eu (Andy)
To: tech@ww
Subject: Re:160m 7 Ferrite Rod Aerial
Thanks John G8MNY ffor one of the most interesting bulletins I've seen
packet for a long time.
I'd like to expand a little from John's ferrite rod aerial for transmitting
with my experiences with tiny aerials for 160m.
I have an FT817 (5 watts) and a homebrew multiband aerial which covers
160m. I really wanted to see what could be acheived with a truly
portable system on 160m.
The ATU consists of a series tuned circuit, one inductor which
is wound on an FT240-61 toroid and a variable capacitor. There are two
1.5 metre legs either side to form the aerial.
\ /
|
|
|
________________ |
L | 1.5m telescopic whip
L |
L |
TO TX |____|
C
C
________________C
|
| 2x 1.5m radial wires
|
|
|
/ / /
The arrangement above can be tuned from 600Khz to 50Mhz.
I have worked upto 8000 miles on ther HF bands with it and around
europe on 40m with just 5 watts. I have not made any QSO's on 80m yet,
but I have on 160m.
Best DX on 160m is 3 miles over ground at 5 watts ;-)
Perhaps 160m walkie talkies are possible, this is compareable
to typical 144Mhz simplex QSO's on a handheld over ground.
I have experiemnted a bit with how useful the radials are.
Test show that having 1 radial (1.5 metres) gave a 3dB improvement
and increasing the number of radials to two gave a firther 1.5db.
So two radials gave me a total of 4.5db over a radial-less system.
Perhaps you could tell us what your best DX is John (by bulletin) ?
73 - Andy, G0FTD @ GB7PZT
Message timed: 08:49 on 2008-Jun-28
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