W5GT wrote:
My G5RV works fine for me on 12M and 17M. Not a beam, but since it's only at
15', I'm happy. My IC756 does have a built in tuner, so I'm sure that helps.

I had to increase the 450 ohm tuned section length on my G5RV
to 36 feet to obtain a low 50 ohm SWR (no tuner) on 17m.

EZNEC says the standard G5RV, with 1/2WL of 20m tuned section,
will present an impedance of about 38-j270 to the coax with
a resulting SWR of 40:1. That would be pretty lossy for 75 ft.
of RG8X, maybe even lossy enough to make your IC756 happy. :-)
--
73, Cecil http://www.qsl.net/w5dxp