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If you can get hold of a VNA and see what the impedance looks
like, you could make a two-stub tuner from coax. 6:1 sounds like
the coax outer has corroded away or something, was the match ever
OK, or has it always been off? Does it change across the band? If
so, what is the curve like?
A NanoVNA would illuminate the problem. Loads of examples of
two-stub tuners out on the internet.
6:1 sounds like something disastrous though.
On 15/02/2021 23:12, ian hope (2E0IJH)
I have a long term problem with my 17 element MET
Yagi. The VSWR is rather high at about 6-1 and I
cannot risk blowing my new radio!
I have no way of taking down my pump up mast to
adjust the matching on the antenna. The current
restrictions mean I cannot get my fellow club
members around to help me drop the mast.
As this means my activities on 432MHz have to be
put on hold for possibly many more months I need to
find an interim solution. In the mist and cobwebs of
mind I recall an ATU for UHF frequencies. I did a
quick search and nothing came up.
Can any group member confirm if an ATU for 432 MHz
is practical and if so any reference to one?