SSB backstay aerial

[MicHughV]

My girlfriend at the time had a father that was an old school Ham...his backyard was festooned with antenna's of every kind. He had an entire room in his house that was filled from top to bottom with radio's, etc. He is the one that got me into Ham as he didn't want me to be traipsing off around the oceans with his daughter, without the ability to stay in touch with us. He suggested the end fed wire contraption I had on my boat. That boat had a steel hull, which may have contributed to the usually excellent performance of my rig.
He also had a sailboat and would rig some or other dipole antenna on it. I never saw how he did it, but he told me it bang out a signal anywhere.

Mind you, his morse code ability was stunning. I prided myself on 20 wpm, but that was chump change for him....to him morse code was a "language"...he didn't have to write anything down....simply listened to it.

[Andrewpatrol]

Another idea I’ve had - what about using a cap-shroud, once the spreaders are insulated. Only thought I’ve got on it would be to insulate lower part to avoid RF burns and sorting an access for thru deck connection. The other thing is situating tuner below decks where things could be getting busy. But it keeps components close together.

[MicHughV]

I've heard about a shroud being used as an antenna for HF before, though I've never seen one in practice. I'd be interested to read comments from those that are more familiar with this.
I must assume it would be single shroud, and not a side by side shroud situation.
The proximity of other shrouds, spreaders, mast, etc, may prove to be a detracting factor.

I await with bated breath to know.

[team karst]

A sailboat with metal rigging, a metal mast or two, and a metal boom or two represents a complex near field environment for a HF antenna. But, it can be modeled. One of the reasons I use a whip at the rear side of my cat.

[ka4wja]

Andrew,
You're very welcome!

As for an "alternative backstay antenna" (try not to use the word "dummy" antenna, as this refers to a "dummy antenna" / "dummy load", which is a big resistor used to transmit into, for radio testing....using the word dummy to actually refer to an antenna is going to confuse many people!)


So, as for an "alternative backstay antenna", go-for-it!
They work well, and have been used by some sailors for years....

(the first application of this I saw, was in the late 1970's, on a nice offshore racer with hydraulically adjusted backstay tensioner....they rigged another length of wire with insulators, from masthead to stern, and fed that from the tuner immediately below...and, btw, this older remote tuner was not our modern "auto-tuner", but rather a remote-controlled, 12-position, stepper-motor-driven remote tuner, that needed to be professionally installed, and each "channel" tuned separately....with two capacitors to adjust and one coil tap to move, for each channel....that's 36 different adjustments!!! Using just a Bird watt meter, a fluorescent light bulb, and a screwdriver!! It took hours to do it!!! Ah, thank goodness for auto-tuners!)

Originally Posted by Andrewpatrol

Thanks for taking the time John. I actually read about using a seperate “dummy” backstay as MicHugh suggests which sounds a good workaround. Just need to work out if it’s possible given all the other things going on such as boom gallows etc,
Anyway thanks to everyone for input.

Just remember that the antenna starts at the tuner (actually the tuner is part of the antenna), and the first few feet of wire (GTO-15) is a very important part of the antenna....so, when planning your design / install, take this into account.



On a side note...I, myself, have hoisted a wire up a halyard as my HF antenna on a few boats (usually deliveries)...works okay....(one time I had a 10-watt 40m/15m/6m ham radio, and had nighttime pile-ups on 40m from EU and on 15m had many folks calling....no ground connection, no tuner....just a ~ 30' piece of wire stuck in the back of the radio, and 12vdc power from a couple alligator clips on the ship's battery posts....)



As for using a shroud....also done this...
--- On my present boat, I have an aft-lower shroud insulated at the top, and I feed it from below at the chainplate, as my HF-DSC receive antenna / HF-WeFax receive antenna....works great! (see my videos of both HF-DSC and HF WeFax reception....these are coming from this ~ 22', aft-lower shroud antenna, not my main backstay antenna!)


--- Once I fixed a SSB radio install on a catamaran that was using one of its outer shrouds as an HF antenna (and had 3" wide copper strap to Dynaplate), and this worked great....
fyi, their SSB problem" wasn't the radio or antenna, but rather the 12vdc wiring (it was run thru the breaker panel) and lots of on-board receive RFI....moved radio chassis (M-802) closer to batteries and ran 12vdc wiring direct to batteries...and turned off most of their breakers on the DC panel, and had GREAT HF comms!!


---- Many years ago (1970's - 1980's) I used a length (~ 30') of GTO-15 wire wrapped around an outer shroud as a LW/SW receive and WeFax receive antenna....lasted decades and worked great!! (also used a VLF converter to receive the BBC LW shipping forecasts on 198khz....worked great!)


---- Also, many years ago (1970's) had an insulated outer shroud on a mizzen mast (ketch) that was used as a LORAN-A antenna (and then as a LORAN-C antenna)....worked great!


So, while you could use a shroud as your HF antenna...it's not my first recommendation...(but, no worries about RF burns....who is going to be hanging onto that piece of rigging, while you're below transmitting???)

The reason I mention all of these is NOT to encourage you to load-up a shroud, but rather to show what does work....and to remind you all that we were all using HF radio on-board for many years....before there were even personal computers, let alone antenna modeling software!!!
And, with the wide variations of masts and rigging, solar panels, wind gens, radar scanners and poles, davits, etc. etc....the most prominent antenna modeler of our modern age (the late LB Cebik) told me personally that he'd give it a go, but would probably be a waste of effort, as the results would not be transferable to other boats....
Please read thru the link that Celestialsailor posted, and you'll see all the details there...
Or...

Or, even better....don't over-think this!
Don't worry about "modeling"!
Just follow most of the instructions and the installation recommendations / advice given here, and you'll be good-to-go!


I gotta' go...
Good luck and Fair winds!

John