Well, I've installed a copper strap (3" wide, 22 mil THICK (roof flashing) and ~30' long, mostly below the waterline against the hull interior) from my AH-4 Icom tuner (designed first for ham radio) mounted directly below the port backstay, down & across the boat to two sintered bronze grounding shoes (4x12 and 6x18) that were already on the boat outside the hull amidships on the starboard side.
The other side (antenna side) of the tuner is connected to the bottom of my port backstay (GTO-15 high voltage wire), BUT the (port) backstay 'antenna' is not yet insulated from the rest of the rig nor my DC ground which is part of my bonding system (haven't gotten around to installing my already-purchased Hayn Marin Hi-Mod backstay insulator yet). This fact is at the root of my long-winded question (see below)...
I've got an Icom 746 ham radio hooked up to that antenna (currently the entire rigging system). While the RF ground is isolated from DC ground on the ground side of the tuner, the antenna side of the tuner is not, as I currently have continuity between my backstay and DC grounds on the antenna side until I insulate 45 feet of the backstay.
I'm receiving like GANGBUSTERS on 80, 40, 20 meters so far, but have been reluctant to hit the tune button for transmitting. Should I be scared about trying to load up the whole rig (backstays, mast, shrouds, through-hulls, etc.)
which is ALSO connected to my bonding system/DC ground/battery negative (but separate from my RF ground)?
Also, before I cut into (one of my two) backstays, is there any antenna length I should avoid for 6-80 meters (ssb AND ham)? I know in ham you should avoid a half wavelength in some antenna designs, but not as clear on marine ssb which I'll be adding soon.
Is this even an issue with an end-fed wire antenna like a backstay (like it most certainly is with dipoles)? I'm currently planning to insulate 45' of my 49' port backstay (one insulator down 4' from the masthead, and the bottom of the stay is already isolated in the glass deck, so I do not plan to insert a second insulator there - will protect from RF burns, however, with PVC).
Add another 3 feet or so of GTO-15 wire connected BELOW decks to the isolated chain plate to the tuner, yielding an effective radiator of about 48'.
The only antenna length issue I'm thinking MIGHT be on 10 meters (28-29.7 Mhz) where a half wavelength is 17.56' (3rd harmonic at 52.7 feet? Dunno). Any additional antenna length considerations before I start sawing away at my 5/16" 1x19 backstay? for marine ssb freqs?
Thanks. You guys are the best! I come with questions, and ALWAYS get answers here !!!!
73 Gene K0GKJ