Topband: Inverted L with elevated radials for topband

[Bill Stewart]

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 at contesting.com>
To: "topband" <topband at 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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