HI from S/V Nomadness
Bit of an odd antenna
theory question, and I could probably answer this with an evening spent on a much-needed refresher in the ARRL books
. But I bet someone here has already dealt with this.
I have twin backstays
on my Amazon 44, one of which is insulated and connected to an Icom
802 in a pretty traditional configuration (including a big mica capacitor for RF ground to my steel hull
, but that belongs in a different thread).
I'm in the process of adding a 480-watt PV array, split half-and-half fore and aft of my radar arch
. The forward half is constrained by the backstays
and boom end, so includes a notch with an inch or so of clearance for the stays (wild guess on how much needed to avoid mechanical interference
on various points of sail). The structure is stainless, and is insulated where there is potential for the backstay to make contact as things sag, stretch, bend, or get leaned upon.
All good so far, but I'm wondering if there is a potential impedance bump, so to speak... I can't quite picture what the impressed RF will do with this big metal hole. It is approximately 4 feet up from the bottom insulator and the GTO-15 connection, which is perhaps that much again from the actual start of the active element (the output of the tuner). Of course, this is just a second instance of the radiating element passing through something metallic, given the steel deck
, and that is no big deal, so I'm probably worrying needlessly.
My gut feel is that the tuner will just deal, and any distortion of the radiation pattern is just a fact of life, not really important... the high-voltage end is up near the masthead.
Any RF gurus wish to corroborate this assumption, or raise any cautions I should consider? Just making sure I'm not introducing a problem...
Thanks and 73,