"Richard Ferryman" wrote in
news
I have constructed a simple telescopic dipole for 2M to 6M to use with
my FT-817ND. This works fairly well but it is prone to RF on the
feeder and some noise pickup. This is almost certainly the result of
feeding a balanced antenna with unbalanced coax. As I need a wideband
balun I can't use traditional VHF tuned baluns. Question is which
type of balun can I scale up (down?) to VHF from HF and maintain
efficiency? Toroidal balun? Ferrite choke? Coiled coax? If ferrites
or iron dust cores are involved then what mix?
Here is a design:
http://www.vk1od.net/balun/G1-1-FT140-61/index.htm .
There are many alternatives.
Owen
Any ideas?
Dick G4BBH