Hello,

Have a scanner in which I listen from 25 MHz or so up thru the vhf and uhf
scanner frequencies of 1.3 GHz.
Presently, one desktop scanner connected full time to one Scantenna in
attic.

Will be buying a handheld scanner, which I will be using (when not being
used in a mobile mode) in probably one of three other rooms in house.

I would like to connect a new antenna in the attic also, but have coax
brought split out to the three rooms
as ports for the handheld to be plugged into.

Only one of the three ports will ever be used at any time.

a. Do I need a "Coupler" between the three branches from the new antenna's
feed ?

b. If not, will the two Unused ports need to be terminated, or is just
hanging open fine ?

c. Anything else I should probably be asking about this proposed setup ?

Thanks,
Bob

On Oct 13, 1:39 pm, "Robert11" wrote:
Hello,

Have a scanner in which I listen from 25 MHz or so up thru the vhf and uhf
scanner frequencies of 1.3 GHz.
Presently, one desktop scanner connected full time to one Scantenna in
attic.

Will be buying a handheld scanner, which I will be using (when not being
used in a mobile mode) in probably one of three other rooms in house.

I would like to connect a new antenna in the attic also, but have coax
brought split out to the three rooms
as ports for the handheld to be plugged into.

Only one of the three ports will ever be used at any time.

a. Do I need a "Coupler" between the three branches from the new antenna's
feed ?

b. If not, will the two Unused ports need to be terminated, or is just
hanging open fine ?

c. Anything else I should probably be asking about this proposed setup ?

Thanks,
Bob

At least a splitter that provides some isolation among the ports is a
good idea. If you just parallel three terminated lines and connect
them to antenna output, you'll have some mismatch loss--6dB worth.
And if you forget to terminate one or both unused lines, they'll put
lots of nulls in the frequency response.

A splitter won't give you a whole lot more signal, since 2/3 of the
power goes to the terminated lines: you have a loss of 4.8dB in the
ideal case.

A couple of other options: get an amplifier with three outputs; it's
possible to have very good isolation if the amplifier is done right.
Or...run the cable "daisy-chain" fashion, with a little jumper in the
first two rooms. Remove the jumper and connect to the antenna feed if
you want access in that room. Don't need to worry about terminations
that way, just jumpers. Cable loss starts to add up, especially on
UHF, but if the runs aren't too long, it probably beats the loss of a
splitter.

Cheers,
Tom