I operate an antenna with a full size DB-224 and an 8 dipole 440 antenna on the
same mast and found that the 2 meter transmitter does not bother the 440
receiver, but I do get some desense with the 440 transmitter into the 2 meter
radio. An extra bandpass cavity on the 2 meter receiver cleared that up. GE
Mastr II on both bands.
I think that the 2 meter dipoles can absorb more power from the 440 antennas
than the other way around, since the third harmonic is resonant on the 2 meter
dipoles.
I have also operated a DB-224 on 440 with some success.
I tried a diplexer to combine the two antennas to one feedline without much
success. I wound up using a separate feedline for each antenna and it worked
much better.
73 - Jim W5ZIT
--- On Mon, 7/20/09, tahrens301 <tahr...@swtexas.net> wrote:
From: tahrens301 <tahr...@swtexas.net>
Subject: [Repeater-Builder] DB Products VHF & UHF on same mast?
To: Repeater-Builder@yahoogroups.com
Date: Monday, July 20, 2009, 10:11 PM
I've got a DB-224 that is going up the tower in a
while when I get the hardline, but control issues
have changed from land line to 440mhz control.
So I need 2 antennas.
Today I saw a hybrid DB antenna, effectively a 224, plus
a 16 element DB, all on the same mast.
Is this something that can be done without having each
antenna interact with the other? Sounds like a good idea
to me.
Just curious,
Thanks,
Tim W5FN
