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Old 22-09-2014, 19:13   #1
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SSB Antenna Length

Hi,
I'm very new to the SSB world but I'm learning a lot from all the threads. However, sometimes too much information becomes overwhelming without some hands on experience so I'd like to get the system up and running and experiment if needed.

Some background:
My mizzen to 25' 6" tall and the backstay is about 31' 6" long. I'd like to use the mizzen mast if possible as it offers the most unobstructed setup.
I want to use the SSB for weather, nets and emergency communications.
I have a Icom-M700PRO, Icom automatic antenna tuner, Practor modem and KISS
I've come to the conclusion that I'd like to use a rope antenna. It seems the easiest and most cost effective. I like the idea of the plastic coated SS lifeline going through a braided line.
The two options I have come up with for hoisting it are:
1. Hoist it with a halliard (we have an extra one on our mizzen we currently don't use). This would be amidship and is as far from other rigging as is possible.
2. Using standoff blocks and running it up the backstay. From what I've read this is not the best idea as some of the power will transfer to the backstay. But I've read conflicting posts about that. The reason I'd consider this is because it is the cleanest option.

Questions:
1. Will a 30' antenna work for the applications I would like to use it for? If this isn't long enough, what is the minimum length people would suggest using?

2. Is running the antenna up the backstay a bad idea? If so, why?

3. Will crimping the GTO-15 to the SS lifeline be sufficient for connecting the two?

Thank you for your input!
Jonah
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Old 23-09-2014, 14:36   #2
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Re: SSB Antenna Length

Jonah,
Good show, asking and learning!!
No info overload from me today....(yes, unusual, but I'm trying a new tact...


1) First off, there is NO ideal length for a marine SSB backstay antenna....no matter what others may say...some lengths are better than others, for some frequencies, and there is an "average length" and a "length which works well overall", but not one "perfect" length....
Yes, longer lengths (60' - 65') favor the lower freq bands, and shorter lengths (20' - 30') favor the higher freq bands....and most cruisers usually end up with a length of 45' or so...

In brief, understand that you're effectively designing an antenna that needs to cover several octaves (typically from 4mhz thru 22mhz or even wider), and allow comms from 25 miles, out to as much as 10,000 miles....and doing it with just a piece of wire!!
What everyone ends up with is a compromise antenna...so, don't fret it too much...

{but, my general recommendation is always to go longer if you can... a "backstay antenna" or "rope antenna" 40' - 45' long, is going to be better than one 25' - 30' long, for use on the most often used bands from 4mhz thru 8mhz (and is damn close to ideal for 8, 12, 14mhz)...although this does depend on the rig, stays, and other clutter, etc...so the "ketch" is a special case where you may want to try the shorter version first, and then go longer if you find performance suffering on the lower freqs...
Also, remember as the solar cycle winds down in the coming 3 - 5 years, the higher freq bands (above 14mhz / 16mhz) are going to be of little use...so it is the lower and middle HF freqs that you should be optimizing for...}

There is an old thread on the subject of backstay antenna length...
Choosing a backstay antenna length


2) Some OLD references (and old-wives tales) used to recommend staying away from any length of antenna that was 1/2-wavelength or multiples of 1/2-wave, long....as the old tuners had difficulty obtaining a match...(remember the entire length of wire, GTO-15 and whatever wire you use hanging from the mast / halyard, is all you antenna...)
However, the newer tuners from Icom, SGC, etc. can typically provide a match/tune for the radio, into any reasonable length or wire...

If you're curious/concerned you can make a quick calculation...(it depends on where you mount the AT-130 tuner, how long of a run of GTO-15 up thru the deck / how long the entire length of wire will be...)
Just divide whatever the total length of wire you'll have into 468, and that'll tell you the approx. freq that this length is a 1/2-wavelength at...
Ex: 468 / 30 ft = 15.6mhz or 468/35'=13.37mhz, etc.


3) You may wish to use either the SS lifeline wire alone (a rugged design that will last a long time), or choose to use a insulated copper wire (insulated tinned copper wire of any gauge heavy enough to last a long time, such as 14ga or so...) inside the rope (if done correctly will also last a long time)....
There is no need to use SS lifeline wire inside a rope...



4) See my specific answers in red....

I'm very new to the SSB world but I'm learning a lot from all the threads. However, sometimes too much information becomes overwhelming without some hands on experience so
-You're doing great....
Read this thread and watch the videos, and you'll learn a lot...

Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call


-And, I'd be remiss if I didn't also steer you to this discussion here...
EPIRB Activation? What happens/How to improve rescue odds

While it's not on-point in a discussion of "SSB antenna lengths", it IS very important for anyone venturing outside the sight of land, and especially for someone that doesn't have MF/HF-DSC Distress signaling capabilities....
Making sure that your EPIRB is properly / accurately registered, as well as freshly serviced and batteried, is very important!!
And EPIRB registration is FREE, and done on-line takes < 5 minutes...
Please read that thread/discussion and FOLLOW the links provided in it (especially the SARSAT-COSPOS and "Cruising World" links to Beth's article)....



My mizzen to 25' 6" tall and the backstay is about 31' 6" long. I'd like to use the mizzen mast if possible as it offers the most unobstructed setup.
-This is a good idea...although some find the somewhat shorter than normal antenna (which favors the higher freqs) to be a disadvantage on the lower frequencies (such as 4mhz and 6mhz) where a good deal of "cruiser's nets" and short-range comms take place...
A "ketch" is one example of sometimes the shorter antenna can be just as good...(but sometimes not...)

Keep the end of the antenna wire a couple feet away from the mast (this means that your 31' 6" distance is going to yield a max length of about 29', PLUS whatever length the GTO-15 is...)




I want to use the SSB for weather, nets and emergency communications.
I have a Icom-M700PRO, Icom automatic antenna tuner,
-Please read the thread referenced and watch the videos (yes, many of them DO apply to you, even though you don't have an M-802....#4, 5, 6, 8, 9, and 10...)
Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

And, for lots of info on weather, etc...
Offshore / Hi-Seas Weather data / forecasts

And, for "nets"....
West Coast Nets
East Coast Cruising Nets



Practor modem and KISS
- Even those that do not have a PACTOR modem should take great care in installation and follow Sailmail's recommendations to the letter!!
- Please make sure you follow the Sailmail Primer (and all the Sailmail application notes) for details of installation requirements (as well as set-up tips/instructions, not the least of which is correctly setting your drive levels to allow optimum thru-put and the least interference)....
Failing to do these things, will cause you much frustration!!

SailMail Primer


-Other than you can build your own for FREE in < 5 minutes, I no longer comment here about the KISS....
But, if you wish to see what it is, and isn't, have a look here...
Re: KISS-SSB Counterpoise
SSCA Forum € View topic - KISS-SSB Counterpoise




I've come to the conclusion that I'd like to use a rope antenna. It seems the easiest and most cost effective. I like the idea of the plastic coated SS lifeline going through a braided line.
-As I wrote above, you may wish to use either the SS lifeline wire alone (a rugged design that will last a long time), or choose to use a insulated copper wire (insulated tinned copper wire of any gauge heavy enough to last a long time, such as 14ga or so...) inside the rope (if done correctly will also last a long time)....
There is no need to use SS lifeline wire inside a rope...



The two options I have come up with for hoisting it are:
1. Hoist it with a halliard (we have an extra one on our mizzen we currently don't use). This would be amidship and is as far from other rigging as is possible.
-A good approach...

2. Using standoff blocks and running it up the backstay. From what I've read this is not the best idea as some of the power will transfer to the backstay. But I've read conflicting posts about that. The reason I'd consider this is because it is the cleanest option.
-Although just about anything metallic can be made into an antenna and can be strung up in some fashion, to work to some extent.....what you are trying to achieve is the "best overall antenna" for the money / space, that you have...AND one that lasts and works WHEN you really need it to work...
For those reasons along, this is NOT a good approach...
Your first option is much better!!!
(not to mention the physical complexity / cost / maintenance / unreliability, etc....)



Questions:
1. Will a 30' antenna work for the applications I would like to use it for? If this isn't long enough, what is the minimum length people would suggest using?
-Yes, 30' will work....but like everything on-board, there are compromises...
See details above....


2. Is running the antenna up the backstay a bad idea? If so, why?
-Yes....(understand that while almost everything on-board is a compromise, this is one area where there is NO need to compromise, and every reason to avoid doing it wrong...)
a) There are a wealth of "bad" things that can happen....and no "good" things...
b) If you "choose" to load up your rig as an antenna (not a choice recommended by most), you can do so by simply connecting the AT-130 tuner's output to your backstay / shroud / stays / chainplates, etc....
And, save the $$$ of any real antenna....
(this approach does work to some extent, BUT....but is fraught with LOTS of problems, not the least of which is LOTS of RFI, both into other systems on-board and from other systems into your radio....all very bad!!)
c) If run your antenna wire (whether inside a rope, or not) up close to other stays (especially parallel to them) you end up coupling some of your transmitted energy into them rather than into the ether, and cause on-board RFI in the process....AND, on receive you can also find excessive amounts of RFI coming in on your antenna (where you CANNOT filter them out)...
Taken to the limit, this is the concept of the horribly-expensive GAM antenna....
d) There's a LOT more to this, such as shunt-feeding / slant-feeding verticals not being efficient/effective for multiband operation, physical complexity, RFI, systems failures, etc...how much do want to know??

Just keep your SSB Antenna away from as much other "stuff" as you can....and do not allow it to run parallel, in close proximity to other wires or long metal objects....
And, remember that the WHOLE thing IS your antenna, from the time it leaves the top terminal/insulator on the AT-130, it is ALL your antenna, so getting it in the clear and away from any other wiring / metallic objects is always recommended!!



3. Will crimping the GTO-15 to the SS lifeline be sufficient for connecting the two?
-If done correctly, yes....this will be a good approach...
(See btrayfors posts / pictures on this...)





5) I wanted to very briefly comment here, without stirring up a hornet's nest!!
Quote:
Originally Posted by jonahmulski View Post
I want to use the SSB for weather, nets and emergency communications.
I have a Icom-M700PRO, Icom automatic antenna tuner, Practor modem and KISS
Two important points....one on weather, and one on emergency comms...

a) You'll find a great deal of info on weather info/forecasts here....have a look, as just about everything that you need is either there or links are provided...
Offshore / Hi-Seas Weather data / forecasts


b) Jonah, understand that there are > 500 coast stations worldwide currently monitoring MF/HF-DSC (~ 84 HF-DSC stations monitoring for long-range DSC calls, and ~ 450 MF-DSC monitoring for DSC calls within 200 miles of their coasts), as well as many SOLAS-grade ships at sea....but aside from the USCG monitoring from a couple of their stations and the Aus and NZ maritime authorities also monitoring (and WLO listening on their own channels), nobody else is out there listening for any Voice SSB calls....
This has been the case now for > 15 years, and I'd be VERY remiss if I didn't make sure that you fully understood this...

So, as you do not have MF/HF-DSC capability, you should be VERY aware of what freqs / channels to use and what times of day, depending on where you are located, when you need to call for help....
I do not know where / when you are cruising/sailing, so I cannot give exact advise here and now...
But since your profile says you're in Calif, in general:
Use 12290khz (12.290mhz) and 8291khz (8.291mhz) as your primary distress / safety calling frequencies...(both monitored by USCG out of Pt. Reyes, CA)
And, 14300khz (14.300mhz) a ham radio net frequency, as your secondary (or co-primary) distress frequency...

Here is the USCG info...
http://www.navcen.uscg.gov/?pageName=cgcommsCall

And, there is a good deal of further info available for you here...
Marine HF-DSC-SSB, the GMDSS, "communications stool legs"

Icom SSB Radio Kits & Components




I hope this helps you out, without overwhelming you with too much information....

Ask more questions and/or for clarifications if needed...
And, have a look here, for a wealth of info on marine SSB and all things "marine electronics"...
SSCA Forum € View forum - Communications



Fair winds...

John
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Old 29-09-2014, 19:22   #3
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Re: SSB Antenna Length

Thank you for the in depth reply John! I really appreciate all the information. I am going to go through it all and links you posted in the next day or so and I'll post any questions that come up.
Cheers!
Jonah
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Old 18-11-2014, 12:35   #4
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Re: SSB Antenna Length

Another question:
Is there any issue with the antenna wire coming out of the tuner and running horizontally inside the boat about 12ft until it reaches the point where it exits the deck and goes upwards? transmission/reception issues? Heath issues?
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Old 18-11-2014, 15:51   #5
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Re: SSB Antenna Length

if you are a paranoid tin foil hat wearer, there is RF energy being released from the antenna wire beginning at the exit from the tuner. the antenna begins where it exits the tuner not where it attaches to the backstay. Since the wire from the tuner to the backstay is subject to interference and shielding by stuff in the boat, it is recommended that the tuner be located as close to the backstay or whatever is the exposed antenna as possible. The coax wire from the radio to the antenna tuner is shielded wire and does not transmit significant energy.
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Old 18-11-2014, 16:01   #6
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Re: SSB Antenna Length

Jonah,
Yes, there are issues doing things like this, and nobody would ever recommend doing this...
Whether you'll find them detrimental, or just an inconvenience, is unknowable....(but, there is no reason to try it...as using your AT-130 should allow you to mount it in a workable location, where it will be near where you wish the antenna to be...)


Specifically...
Quote:
Originally Posted by jonahmulski View Post
Is there any issue with the antenna wire coming out of the tuner and running horizontally inside the boat about 12ft until it reaches the point where it exits the deck and goes upwards?
Yes, this "12 ft", is not only part of your antenna, but the can be the most important part of your antenna....if this is the high current point at some freqs (such as the lower freqs, < 8mhz, where your fairly short antenna will always be a "current-fed" base-loaded antenna), then this would be VERY bad, as most of the radiation occurs from the high current points along an antenna....
And, even on higher bands, this is still a pretty bad idea...


transmission/reception issues?
For receiving, you will be allowing significant RFI pick-up by the long antenna wire inside the boat (and presumably near sources of RFI)...as well as reducing the antenna's efficiency/effectiveness in picking-up the "wanted" signals (other radio signals).....

For transmitting, in addition to placing significant RF in close proximity to other electronics on-board (probably causing RF ingress into these other systems while transmitting), you are also putting most of your transmit energy into a very low horizontally-polarized (and "indoor") antenna (and fairly poor efficiency antenna), which is the opposite of what is desired for long-distance skywave communications....


Overall, placing your AT-130 near where you want your antenna is the best approach...

A couple feet of GTO-15 running thru the deck and down to the AT-130 is fine, but keep this part as short as possible and do NOT run it parallel to other wiring nor other metallic structures (such as railings, etc.), and try to keep it away from other wiring as much as possible...
(my GTO-15 does run about 1.5' away from, but perpendicular to, my GPS SeaTalk data output, and while I'd not recommend even going that close, it has worked fine for me.....keep it short, keep it away from other wiring, and keep it as "vertical" as possible....and you'll be fine...)


Heath issues?
No....no health issues to concern yourself with...

EDIT...
Peter (roverhi) and I were typing at the same time....and we are in agreement....



I hope this helps...

John
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Old 18-11-2014, 17:07   #7
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Re: SSB Antenna Length

Quote:
Good show, asking and learning!!
No info overload from me today....(yes, unusual, but I'm trying a new tact...
John, your new tact (sic) is neither port nor starboard, but still pretty damn long!

If this is the short version...

But, as always, your tech advice is worth reading.

73,

Jim N9GFT/VK4GFT/MM
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Old 18-11-2014, 18:18   #8
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Re: SSB Antenna Length

I probably just learned out why our hf radio is only so so. Our tuner output lead is bundled with other wires and horizontal to boot.
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Old 18-11-2014, 20:12   #9
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Re: SSB Antenna Length

Quote:
Originally Posted by jonahmulski View Post
Hi,

1. Will a 30' antenna work for the applications I would like to use it for? If this isn't long enough, what is the minimum length people would suggest using?
The specification for your tuner will say what lengths of antenna it will work with.
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Old 18-11-2014, 22:08   #10
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Re: SSB Antenna Length

Guy, I don't know what radio/tuner/antenna system you have, but assuming it is like everyone else's, yes this description you give is very likely a big part of why your system is just "so so"!!
Quote:
Originally Posted by Guy View Post
I probably just learned out why our hf radio is only so so. Our tuner output lead is bundled with other wires and horizontal to boot.
Although you do know now, just for everyone else's benefit allow me to reiterate...

The wire coming off the antenna terminal on the top of the remote tuner IS the antenna, or at least the beginning of the antenna!!!
And, this beginning part of the antenna IS very important!!!

And, while I highlighted this importance being especially true for transmitting on the lower frequencies (2mhz, 4mhz, 6mhz, and 8mhz) where the antenna is typically 1/4-wavelength or less in overall length, this is also of great important on higher frequencies where the length of the wire inside the boat (and/or running parallel to other wires) can be a significant portion of a 1/4-wavelength itself....
(both of these reasons are just two of the many reasons why it is so important to install the remote tuner as best as you can to minimize the length of this wire running inside the boat / near other wires....)

Although it should go without saying, but perhaps I should say it anyway...
For both transmitting and receiving, getting/keeping the antenna out and away (as best you can) from other wires / metallic structures is ALWAYS recommended!!!
If for no other reason than because of RFI, both transmit and receive RFI...
And, specifically for receiving....the RFI picked-up by the antenna wire being run along (and bundled with) other wires can be truly horrible (I'm surprised your set-up works at all...)!!!


FYI, I once saw a "professional SSB installation" where the "professional" (sic) ran the GTO-15 wire inside the SS tubing of the stern rail / arch, and then over a few feet to the backstay....(the reason given was that "it looked good" and "it worked".....but the problem with the latter statement is that a "wire coat hanger" stuck in the back of the damn radio would work too, but not very well!!!)

So Guy, don't feel too bad about what you're dealing with....sometimes all you may need to do is move the tuner a few feet (stick in the lazarette, etc.), so it is near the where the stay / whip / etc. ends....

Oh BTW, although having a wire that is rated for 15,000 volts may seem like overkill for our systems (and it is a bit), the fact is that there can be a few thousand volts of RF (at least > 500-800v) on that wire, AND since it is tinned-copper wire, AND since most GTO-15 also has UV-rated insulation, etc. it just makes good sense (and good engineering practice) to use it!!
Yes, some have used just "regular insulated copper wire" from their tuner to their backstay / whip, etc. and have no problems.....if you can afford the extra couple dollars (< $5), there is no reason not to use GTO-15....
(whatever you do....do NOT use coax here....no matter what some try to tell you about only hooking up the center conductor, use of coax here places significant capacitance in series with your antenna....yes, the tuner will compensate for it and show a "tune", but your antenna system performance will be greatly reduced!!!)







Seymore, the question being discussed here is not what length of antenna the tuner will provide a match ("tune") for, but rather what antenna lengths are efficient, etc....so, while looking at the specs will give you some info about what the tuner can do (at its maximum power rating), the facts are this is a rather moot point here....as well as the fact that these modern tuners (Icom and SGC, etc) will actually find a "tune" on lengths much shorter (and longer) than their specs show...
Quote:
Originally Posted by Seymore View Post
The specification for your tuner will say what lengths of antenna it will work with.
As an example the AT-130 (and AT-140) specs show it will work from 1.6mhz thru 30mhz, using a 23' (7m) antenna length....but not only will this tuner operate with a shorter length antenna, if you were to change your lowest frequency of operation to just 3.6mhz (or 4mhz), it will tune almost any length wire....(but using such short antenna lengths gives an EXTREMELY inefficient antenna, and as such would never be recommended except in emergency situations such as when using a make-shift antenna....so, as I wrote above the question being discussed here was more about what efficiencies / effectiveness can be gotten out of backstay (or whip) antenna lengths of approx. 28' - 30'....and the answer is of course: pretty good....

The reason I'm pointing this out is so we don't wander about looking at "specs", but rather try to understand what the antenna (and remote tuner) actually does....and how to make the things work well....






Jim, okay I'm a little embarrassed.....I was going to be brief...but, I just got carried away a tiny bit....
Quote:
Originally Posted by Jim Cate View Post
John, your new tact (sic) is neither port nor starboard, but still pretty damn long!
And, since I do enjoy a long passage, your reference here is actually correct literally and figuratively....
How's that for keeping it short??





I hope all the above is helpful...

Fair winds...

John
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Old 19-11-2014, 03:48   #11
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Re: SSB Antenna Length

Given your aim (WF, nets, emergency communication) a well installed antenna system with 30 ft of antenna wire (from top until the antenna tuners antenna lug) and a good RF gronding system (you ahve a KISS) will always be better than a badly conceived one.

yes 30ft is a bit short for 2 Mhz and 4 Mhz so you will losse efficiency but your still over the best medium = seawater.

"Well installed" woudl be avoiding that 12 ft underdeck part of the actual antenna wire.

Your ATU is compact so for optimal installation I would move it to just under/as close as possible to the bottom of your sloping wire.

30 ft antenna wire is still 1/8 wave on 4 Mhz.
It is optimal from 7 Mhz until 21 Mhz as a steep slloper and over seawater.

Jan
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Old 19-11-2014, 07:35   #12
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Re: SSB Antenna Length

I just learned a bunch. That is some great info there guys.

One question though, I understand how running an antenna parallel to the backstay would be a bad thing but am slightly confused by the name "backstay antenna" then. I thought that's what people were doing.
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Old 19-11-2014, 09:00   #13
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Re: SSB Antenna Length

Rondo,
We are all happy to help....but, please don't read too much into this discussion, as it is a very specific question being asked / discussed....Jonah was concerned that using a somewhat shorter than usual antenna length, would not work properly, and we alleviated his concerns...
Quote:
Originally Posted by Sir Rondo Normal View Post
I just learned a bunch. That is some great info there guys.
For wealth of info, have a look at this reference / index, where you'll find links to more info than you may ever want....
Marine SSB Stuff (how-to better use/properly-install SSB)


One question though, I understand how running an antenna parallel to the backstay would be a bad thing but am slightly confused by the name "backstay antenna" then. I thought that's what people were doing.
Yes, that is what people are doing...
One of his possible solutions (to the non-problem), was to try to run a wire up parallel to his main backstay....which would be both mechanically troublesome (and most probably unreliable), as well as electrically less efficient that either:
-- keeping the antenna wire as far away from other rigging as possible...
-- or, simply insulating the backstay and using this as the antenna...

(and, on his ketch using the main backstay might not be as good as using his mizzen backstay....)

What is commonly called a "backstay antenna" is actually using the backstay (and connected GTO-15 wire from the tuner) as the antenna, by using rigging insulators that insulate a section of the backstay allowing you to use this as your primary HF antenna....
The only "disadvantage" of using a "backstay antenna" is the cost of the insulators...which can be quite pricey, depending on the size needed....
Some sailors say that they have an aversion to cutting a perfectly good piece of rigging wire and installing insulators, and I understand their "gut" feelings....but, the fact is that these rigging insulators have significantly higher working and breaking strengths than the size rigging wire they're mated to.....and in ~ 40 years of seeing offshore sailboat rigging (and some dismastings), I've never seen a rigging insulator break, ever....but, if you want a belt and suspenders approach (as I do), then using a fail-safe insulator such as the Hydn Hi-Mod rigging insulators completely solves this issue (except that they are pricey!!)

Have a look here....this is my lower rigging insulator of my backstay, with the padded Sunbrella cover removed...





And, if you are looking for a wealth of info on HF radio / Marine SSB radio on-board, please have a look at this reference / index page, with LOTS of links to LOTS of great info about LOTS of communications / weather / radio matters....
Marine SSB Stuff (how-to better use/properly-install SSB)



Further, please have a look at these videos....half of which are fully applicable to users of all HF radios on-board no matter what brand/model (some of these videos are also good for those using only "SSB receivers", as well...)
Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call



I hope this helps sort out a few things, without confusing matters too much....

Fair winds...

John
s/v Annie Laurie
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Old 19-11-2014, 10:15   #14
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Re: SSB Antenna Length

I do agree with John that wire antenna's should be kept as far away as possible from other conducting materials of similar long lengths mainly the rigging (stays, backstay, forestay, alu mast) however on the typical 32-40 feet sailing boat it will always be close even the insulated backstay is close to the mast....
If one would be able to model the radiation patterns certainly the coupling into the rigging will cause important radiation pattern distortion hence directionality.
Seawater is the optimal take-off platform for HF waves but then again a sailing boat is complicating things.
Actually the best solution for this would be a 7-10m vertical installed port or starboard side at the transom....not always pratical on a sailing boat this size...

I use the "cheapo" "alternative backstay antenna" so indeed the base is only 1.75m away from the (ungrounded) backstay and gradually comes closer to the backstay moving upwards.
But it is cheap, very flexible since I can change its length easily (when pruning to find an optimal length for the ATU to match easily) or even switch to a length favoring the lower frequencies 2 Mhz-8 mhz.
It doesn't compromise the backstay integrity.

Jan
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Old 20-11-2014, 04:32   #15
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Re: SSB Antenna Length

Thanks for all the links. I have some reading to do, that is for sure. The subject of backstay antennas and rigging has me thinking maybe dyneema rigging might just have another attractive aspect to it.
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