Robert11 wrote:
Hello:

I have a 75 foot run of 50 ohm coax for a receive-only antenna. (30 Mhz on
down)a.

Need another ten feet or so.

a. Any "meaningful loss" if I use a 75 coax jumper rather than a 50 ohm one
?

b. Also, if I use one of those coax T adapters to connect the pieces as I
have a spare one: the kind with a perpendicular male and two in line
females in one small "connector piece", any problem with the unused "port"
regarding reflections or discontinuity losses ? (again, for receive only)

e.g., should I use termination there, or just forget about it and leave the
unused spigot alone ?

Thanks,
b.

Extending the 50-ohm coax with another ten feet of 75-ohm won't be a
problem for receive-only on HF. However you should use a 75-ohm inline
barrel F-connector (female to female)for joining the two coaxes instead
of the 'T' adapter or splitter. The splitter will some signal loss from
both outputs regardless if one of them is not used. You can get the
barrel connector at Radio Shack or most any place that sells TV coax
hardware.