On Fri,3/31/2017 5:00 AM, Martin Pelt wrote:
I am putting a 80 meter 2 element inverted vee beam up. It will be at 120
feet with 39 foot boom.
I have 2 questions dealing with switching from phone to cw without lowering
elements and using jumpers.
I have a 2-element flat Yagi for 80/75 at 140 ft. It consists of two
wure dipoles strung between trees, fed with low loss RG11. I retune the
antenna from CW to SSB by switching in sections of line in the shack on
the dipole that is the reflector. My design is based on a 2-part NCJ
piece by W6AM, who rigged two wires, fed them with a half wave of open
wire line or twin lead, and switched in L or C in a tuning enclosure at
ground level. In my implementation, the L and C are provided by those
lengths of coax acting as open and shorted stubs.
I strongly agree with the advice by others that you MUST model whatever
you plan to do.
73, Jim K9YC
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