In a message dated 2/2/02 6:23:59 PM Pacific Standard Time, ROBKEL@aol.com
writes:
> I have recently put together a 2 element triband quad. 20 & 15 M work good,
> with a under 2.0:1 over full band (<1.4 over most).
> 10m VSWR is unacceptably high (3:1 or so over full band.
> I have checked all connections and dimensions, all OK. Feed is a single
feed
>
> line through a balun and then a length of 75 ohm twinlead to a common
> connection of all three bands.
> I arranged to isolate just the 10 m DE, and it shows a 2:1 VSWR over band.
> I was under the impression such antennas were common an presented a good
> match on all bands. I plan to test the balun soon, and also considering a
> 2:1 W2FMI transformer.
You'll have problems when you feed a quad with the feedpoints tied
together and using one feedline; the 20M loop will radiate when you're on 10M
(14 & 28 mHz). Use 3 feedlines and your problems should be minimized.
Cheers,
Steve K7LXC
Tower Tech
________________________________________________________________________
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