wrote in message
ups.com...
If the antennas are to be spaced more than a 1/2 wavelength (free
space), how can I use a 1/4 wavelength of 75 Ohm coax? I guess I would
have to splice in a 1/2 wavelength multiple of 50 Ohm coax between the
75 ohm coax and the T connection to make up the length.

I only need about 500Khz of bandwidth, so this might not be a concern.
But this was another question I was going to raise. Is there anyway to
calculate the bandwidth that I would see from a 1/4 wavelength
matching section? I guess that is a real easy one to test in real life
though.

Thanks for all the responses!

-Scott, WU2X


Hi Scott

If it is OK to assume the antenna's input impedance is close to 50 ohms.
Any length of 50 ohm line can be installed to a location where the 1/4 wave
transformers can be installed.
It may be confusion for me to add that I have connected two 50 ohm coaxes
in series to make them look like 100 ohms at the junction. I didnt think
the joining of coax center conductor to the outer conductor of another was a
good idea till I did it (after being advised by Mr Richard Clark).
Series-ing coax works quite well at 2 meters when a couple ferrite sleeves
are used to minimize currents on the outside of the shield. That allows
only one 75 ohm matching transformer (which isnt much of an advantage in
your case).

Jerry