Swoozie Pellegrino wrote:
On Feb 12, 8:05 am, "Yuri Blanarovich" wrote:
Try the Half Sloper if you could.
It is quarter wave wire suspended between balcony and run at about 45 deg
down to a tree or whatever. There is a good chance you will end up with 50
ohm impedance and can be fed directly with a coax, shield connected to metal
railing or door frame and center wire to the antenna. Trim to frequency.
Had one like that from the 9th floor at the hotel in Bahamas, worked very
well.

73 Yuri, K3BU.us- Hide quoted text -

- Show quoted text -

I think that I'm going to start with this idea, since I have
a radio coming in the mail and would like to do the simplest
and cheapest up front to get the radio tested out. I have
a few questions:

1. After I wire up the antenna & coax as described above,
can I do my trimming to frequency by using only the radio's
SWR meter, or do I need an external tuner at the wire?

2. This radio can output 100W on HF. Can't this setup
with a 10m length of 26-gauge magnet wire handle
this?

3. I may need to run up to 30' of coax. What type should
I buy?

Thanks for all the help!
~swooz

One thing you should realize about the half sloper is that it's only
half an antenna. The outside of the coax, in your case, is the other
half of the antenna. If you put one amp into the "antenna" wire, one amp
will flow down the outside of the coax. So don't be surprised if you
find strange effects in your shack, such as electronic keyers which keep
sending, push-to-talk buttons that turn on the transmitter but don't
turn it off, RF burns from the microphone, and an SWR that changes when
you move the feedline around or change its length. You might get lucky
and not see these effects if the length of coax to the antenna and from
the rig to the ground is favorable, or you might not. You'll also need
to take care to keep the feedline as far away as possible from power or
telephone wiring because it's radiating just like the "antenna" part of
the actual antenna.

For those reasons it wouldn't be my choice for an indoor antenna, but
apparently Yuri has gotten lucky and had success with it, and so might
you, too. I'm sure you'll get some other suggestions from people with a
lot of experience.

26 gauge magnet wire is fine for most indoor antennas (about anything
except an electrically small loop). RG-58 is fine for the coax, up to a
few hundred watts, if the SWR is fairly low. If the SWR is fairly high
(say, above 3:1) and you're running 100 watts, you might want to use
RG-59 or RG-58x instead.

Have fun!

Roy Lewallen, W7EL