"Sooner or later everything old is new again" (Stephen King)
February 1922 QST page 30
The 1BCG antenna used for the transatlantic tests was a T cage
over a radial counterpoise. The antenna is hung between two pipe
masts 230 feet apart, and 108 and 75 feet high, respectively.
The two horizontal sections of the T-vertical are each 50 feet long.
The vertical section is 70 feet over the top of the counterpoise.
The elevated counterpoise consisted of thirty 60 foot wires
The operating frequency was 1500 kilocycles
http://p1k.arrl.org/pubs_archive/4361
73
Frank
W3LPL
----- Original Message -----
From: "Bill Stewart" <cwopr@embarqmail.com>
To: "Gabriel - EA6VQ" <ea6vq_ml@dxmaps.com>
Cc: "topband" <topband@contesting.com>
Sent: Thursday, March 5, 2020 8:13:08 PM
Subject: Re: Topband: Inverted L with elevated radials for topband
Hi Gabriel,
These comments will be of little help as far as the technical info on the
subject antenna
and is a far cry from an excellently constructed antenna but it is very
practical....in my
opinion of course.
However, I do use an Inv. L with a four wire counterpoise...or elevated radials
if you
prefer. Mine is approximately 50ft vertical and rest horiz....total, a quarter
wave. The
horizontal part is about 50 feet high and fairly flat. The antenna is
completely covered
over with tall pine trees. The CP wires go off from the base/feed point 10ft
off the ground
and at approximately 90 degrees apart. Each CP wire is about ten feet high and
some are
supported on tree trunks, others have some PVC posts for support and seems the
CP wire
lengths are a bit shorter than a 1/4 wave lgth, but my memory may not be too
good on this
part. I feed it with RG8X...I only run 100 watts(CW) on 160....no need for big
coax in my
case. I just used a door-knob cap between the vert and CP at the base....can't
remember the
value but think I just experimented until I got the SWR good....also think I
did some trimming
on the CP wires. I have had very good success with this antenna. With 100 watts
I have been able
to work several DXped. stns in the Pacific, JA. This season I have worked
nearly 80 EU, Carib
and Pac. stations. I had a lot of fun in the recent ARRL CW test. No, I don't
get every station
I call, but enough to keep me happy. The purist, with all their instruments and
computer
programs would laugh at my version, but it seems to be an easy antenna to get
working and,
at least in my case, a decent antenna. (I also use it for receiving...works
well there too).
Try it....easy to put up and if it don't work, go on to something else....hi.
GL & 73 de Bill K4JYS/NC
----- Original Message -----
From: "topband" <topband@contesting.com>
To: "topband" <topband@contesting.com>
Sent: Thursday, March 5, 2020 1:02:07 PM
Subject: Topband: Inverted L with elevated radials for topband
I have some doubts about installing and inverted L with elevated radials for
160m. I have been searching in Google and find some contradictory
information, so I would appreciate very much if you can help me with your
own experience.
The antenna would be supported by a 16 m (52.5 ft) high fiberglass pole
placed on top of a 3m (10 ft) high small tower with the horizontal part of
the L slopping down to a 5 m (16 ft) high mast about 23 m (75 ft) away. Two
to four tuned elevated radials can be placed, although they will have to be
bent due to space restrictions.
Now the doubts:
What impedance can I expect at the feed point with this configuration?
How to match it in order to feed it with a 50 ohm cable? Some pages say
that no match is required, only a choke. Other pages say a hairpin is
necessary as the impedance can be too low. So other say that a tuner at the
base is required? I am confused L
What performance for DX can be achieved by this antenna? Is it really good
or do you have some better suggestion for a really small lot where no ground
radials are possible?
Would it be worth to use a higher fiberglass pole, let's say 4 m (13 ft)
higher, in order to lengthen the vertical section of the L? Would the
difference be noticeable?
Anyone has real experience setting up this antenna with elevated radials?
Most information I can find on Internet is related to ground mounted
antennas.
Thanks in advance!
73. Gabriel - EA6VQ
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