Tam/WB2TT wrote:
"Richard Harrison" wrote in message
...
Wes Stewart, N7WS wrote:
"Do not no.."
6-ft seems sufficient separation at 2-meters or 70-cm to avoid tight
coupling.
First MW BC plant I worked in was in 1949. It had stations at 950 KHz
and 1320 KHz. Both stations used the same antenna tower. Pass / reject
filters kept them out of each other`s final amplifiers.
I think in the VHF / UHF range one might get lucky and select the right
length of coax between an individual antenna and the common feed point
where individual antennas are paralleled and make the antenna at that
point look like a high imprdance to the wrong transmitter. For practical
purposes the wrong antenna disappears, but the right antenna does not.
It matches the coax.
Best regards, Richard Harrison, KB5WZI
Richard,
Since the 70 cm antenna will be a low impedance at 2m, how about connecting
the 70 cm antenna to the 2 (and feedline) with a piece of coax that is an
add multiple of 1/4 wave at 2m? At 70 cm they might both be active. I might
try EZNECing it for a pair of dipoles. Or how about 2 pieces of coax, with a
T connector to the feedline? Personally, I would buy the filters.
Tam/WB2TT.
Exactly what I did , patterns seem fine and they certainly work fine
with a little trimming the VSWR is good in the shack ( yes I know about
the other things but it works fine)
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