Checking traps with a GDO is an interesting affair. I found the hard
way to check with someone who knows about where the traps will show
a dip. Each manufacturer has a different design philosophy which we
need to know ahead of time. Example, if you dip one of the newer
Hy-Gain traps without knowing where it should dip, you'll throw it
out! They resonant megacycles below the band for which they are
designed. I don't remember the exact details, but I do remember that
the 15 meter trap resonates around 19 mHz.
By the way - I wasn't aware of the feed system on the newer Mosely
tribanders. Gawd, it's been a long time since I've seen one. And I
have only owned one (about 35 years ago) and remembered it as a
pretty hokey feed arrangement with the driven element mounted on
insulators.
Thanks to all for the input. de KL7HF
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