"Jon Danniken" wrote in message
...
I was actually thinking of a vertical dipole, as it's what I have on my
roof right now (an old set of rabbit ears, so I can listen to airband
while I get the discone built and figure out a proper mast setup).


Ok on the vertical dipole. For this antenna you need to run the feedline
horizontal from it for a couple of feet and then down.

The impedance of this antenna should be around 70 ohms and if I were you , I
would use some 70 ohm rg-6 coax back to the receiver.




Good to know, thanks. I'm using a 300:75 converter up there right now
(twinlead from the rabbit ears to the coax), I think I'll take it off
and see if it makes any difference.

The 300:75 converter is actually a balun that has a 4 to 1 ratio. It
normally does 2 things, changes a 300 ohm to 75 ohm inpedance such as many
TV antennaas were set for 300 ohms so the twin lead could be used. As
things changed over the years, the newer TV sets had a 70 ohm input for the
coax cable. The 300:70 could be used either way, 300 ohm antenna to coax or
coax to the old 300 ohm input of the TV.

Removing it from the vertical dipole (70 ohm inpedance) and using coax to
the receiver will probably help.




So they'll mostly be located by the transceiver instead of up on the mast?


The baluns can be used either place. Most often at the antenna if coax is
used and at the transceiver if open wire (twinlead) is used,


I have been using the 70 and 75 ohms without paying much attention. They
are close enough it does not mater.




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