Home › Forums › temp › AM Transmitting Antenna: Fat On Top, Thin On Bottom › Appreciate your comments!
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I have read everything from you a couple
of times and I really appreciate it.
My comments will probably be brief because,
unfortunately, this is a day where life is
“getting in the way,” an expression that
I think Neil has used a lot.
This is the bottom line with the antenna
I had a “less than 3 meter antenna” that
worked pretty well. I put a HUGE top hat
on it and there was a significant increase
in signal. The system was ground mounted
with 16 radials. Because of problems with
my poor eyesight I could not maintain the
system and it sort of just fell apart.
There is some debate about the legality of top
hats. I can see both sides of the argument.
So I thought it would be fun to make a
“3 meter stick” that is just larger on top and not
use a top hat. The goal is the same as what
a top hat does – (let’s see if I’ve got this right)
it will increase the radiation resistance and/or
pull more current to the top of the antenna.
So that’s basically it. I’m not sure what it will
look like but it seems that the easiest approach
is to take 4 copper poles, feed them all at the
bottom and then spread them apart some
distance at the top. I’m not sure what to do
after that – but that’s OK because this is a fun
experiment and we will just see where it goes.
Carl’s 49 MHz Part 15 comment above regarding
an antenna element seems to indicate that using
multiple poles together is OK. Also, if you look
at a Part 15 AM antenna like the Bilal Isotron –
well it is made of many pieces and nobody has
To Rich: Welcome aboard! I don’t think we
met before on another board. This is really
the first board I have ever been on. Before
I got on here I knew NOTHING about how
to make a Part 15 station work. I had tried
many Part 15.239 FM set-ups over the years
but never had any luck with AM. Thanks to
the people on this board, I have had some
significant success. So Rich, just enjoy what
you are doing and take your time. I think
Part 15 AM/FM is about the radio/electronics,
the music, and the broadcast history. And
by broadcast history I mean it could be old
radio shows or old broadcast equipment.
So that’s it for now. Thank you for everything