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[KI4VBR]

I mounted a 20 meter & 40 meter Hamstick to the grabrail along the side of my boat.  I also took a twisted, twin-lead, 14g wire attached to the antenna mount (ground), stripped 8 inches of insulation off of it, weighted it and put it over the side in salt water.  I thought I would have a good ground.  My standing wave ratio was greater than 8:1 which the antenna tuner in my IC730 couldn't work out a solution.  I thought I would have a good working antenna setup on the boat, but not so.  Cable checked out OK... In fact, I used two different runs of coax just to be sure, same results.  Any ideas why not?

Are there other easy/inexpensive options that I should be looking at?

Thank you for any and all help offered.

Vince

[VK3LU]

Vince,
Have you tried adjusting the tuning whip at the top?
I don't know the antenna you have but I had a look at the MFJ website to see what the antenna configuration is and found out about the adjustable whip.

Nev

[N1UR]

For a good RF Counterpoise, you are going to need a better interface with the salt water than a wire thrown over the side.

Do some research on HF on Sailboats.

Ed  N1UR

[K1VSK]

While the counterpoise you tried is rather useless, it should cause such a high SWR. Did you use an antenna analyzer to sweep those bands or just tried tuning on one frequency relying on the radio’s internal meter?

[K1KIM]

I would not use the stainless grab rail for your mounting point, but rather mount it on top of your bridge hardtop.

Though, I assume you are only pushing 100W output from the transceiver, it is far better above your head than along side it at the helm.

[K4LIX]

A Ham friend of mine mounted an Alpha Moto vertical on the rear rail of his sailboat and it worked very with his TS-140 for 20m and 40M.

[WB6BYU]

The length of the ground wire between the feedpoint
and salt water is part of the effective antenna length,
and affects the resonant frequency (at least assuming
the rail it is mounted on doesn’t serve as an adequate
“ground” by itself, but it looks too short for that).

I doubt that the antenna has enough tuning range to
accommodate it.

I’d think it would work better mounted on the deck
railing, which is much larger and (assuming the pieces
are all solidly connected together) would make a
better ground system.

Otherwise, add a couple 1/4 wire radials for each band
connected to the mounting bracket and run the
around the boat in opposite directions.

You don’t need an actual connection to sea water to
get the benefit of low angle radiation, at least on
the higher bands where you have enough metal
mass or effective radials.  That’s more important
on 2182 kHz or other low frequencies where your
boat is too small in terms of wavelengths.

[WA3SKN]

Is the grabrail even grounded?
The tuner in the ic730 is not a wide range tuner.  You should turn it off and use a separate tuner for matching.
The railing may or may not be grounded, and you probably want to ground to the engine block anyway and make sure the zincs are in good condition.  That grabrail should provide enough for a radial if there is good metal-to-metal connections all around... you could check this with an ohm meter  to make sure.
The ham stick will probably not handle the salt air too long.  They did make a fiberglass antenna for the old marine band that would work... if you can find one.

-Mike.

[K5LXP]

Your "counterpoise" is acting like a long radial, and likely the resonant frequency is much lower than the hamstick would otherwise tune to.  Look at it more as an OCF than a vertical.  Seawater is not a counterpoise, or radial field.  The enhancement you get from it is far field, not from a wire dangled in the water.  By picking a hamstick you're choosing a specific solution which is a part of a system, without considering what the rest of the system needs to look like to work.  There is probably a mount location and radial configuration that will make a hamstick work, or for the same effort you could make a better antenna work.  Define the goal (bands, pattern, efficiency), that will drive the antenna configuration, then the rest comes down to deploying it on the craft. 

Mark K5LXP
Albuquerque, NM

[WA4MP]

I'm not sure it'd meet your cost objectives, but you might check marine sources for the 20-foot+ fiberglass antennas and auto-tuners used on ocean-going boats/ships for HF/SSB. Any system that will handle those bands, grounding issues and all, should work for the ham bands. And they'll also be designed for a salt-water environment.

To save money, you might check out used. There are boaters so rich they'll replace an antenna when the chrome starts to show a little rust.

[K4WH]

Been there and got the Tee Shirt as they say.  Do it right, or just forget it.  As was said before me, go to a marine radio/communicatons store and ask them.  Going to cost you, or just window shop and find the stuff on your own.  I did a quick check on the web and found lots of vertical 40 - 10/6 meter antennas.  Icom 730  ?? if its the one I'm thinking of, it's old and was never very good when new.  How about looking for a Icom marine band radio.  The one rig they have has 150 watts out and covers all the bands.  Then as someone else said by a marine matching unit/tuner.  Anything on a boat takes an extra hard beating and you may think the inside of a boat is out of the saltwater environment, but its not, even when you close up the boat

[KA4WJA]

Vince,
1)  First off, as you've found out, there is a lot more to this....and, I do think I can help.  (I've been using HF comms on boats, since the late 1960's....assisted in my first HF maritime install in 1973...and I've installed/used/troubleshot many systems since then, both maritime and ham....and currently using Icom M-802 on my 47' sloop now for years....yes, I installed all of it myself, including the nav station design, antenna system, radios, instruments, etc. etc...I did it all, and have the same on other boats as well...)

Here's my Nav Station:



And, here I am, rafted-up in the Azores....yes, I used HF comms (both ham and maritime) all the way across the Atlantic (yes, even in 2007 and 2008...at the bottom of the solar cycle)
https://jerodisys.com/C470/470pix/4707820.htm

And, fyi, sitting at the dock here in S. Florida, I still receive Australian HF Maritime weather forecasts (both HF-SSB Voice and HF-We-Fax), right here sitting at the dock....but, don't have a pic of that, so here's a pic of a chart from US NWS, transmitted by USCG.



But, I do have a short write-up of what I still get, sitting dockside here in Florida...
https://www.cruisersforum.com/forums/f13/good-hf-wefax-reception-on-board-at-the-dock-march-2021-real-world-248424.html


BTW, Vince, I assume you have an Icom IC-7300?  And not the older Icom IC-730?  (they are VASTLY different radios....and, the IC-730 doesn't have a built-in tuner)


a)  Be aware that even if set-up with adequate counterpoise / ground system (which is one-half of your antenna ---- the "hamstick" being the other half), a hamstick (especially on 40m and below) will exhibit a rather narrow SWR-bandwidth, and you should be testing your VSWR across the whole 20m and 40m bands, at 20-25 khz increments...in order to find a resonance, and see what the VSWR bandwidths on various antennas / counterpoises are.


b)  Your 14ga wire is (along with the SS grab rail) is acting as your counterpoise ---- it is the other half of your antenna....it is NOT simply "connecting" your antenna base to the sea water!   And, as such, this 14ga wire and your grab rail are part of your antenna, and my best guess is that they are in fact a bigger part of your antenna than the "hamstick" itself!   And, since they are of unknown resonance (non-resonant), it's not surprising that you cannot find a good match on either 20m or 40m! 

Stop here, and turn OFF the internal tuner in your IC-7300....as we will need to "tune" the antenna and counterpoise to get close-to resonance....and, then, only then, should you activate your 7300's internal tuner, to present a good VSWR to your rig's transmitter!

If your grab rail is isolated (meaning mounted into the fiberglass and not connected electrically to anything, like a "bonding system") and you knew its approx electrical length, you could experiment in the exact placement of the hamstick whip mount, along this grab rail, and if needed simply add some wire onto the ends of the grab rail itself, to make a sort-of 20m ground-plane antenna out of your 20m hamstick, and that should work well for you!     (you'd in effect be using the grab rail and any wire you attach to it, or to the antenna base itself, as your radials of the ground-plane antenna)

For 40m, we have the issue of the size of a counterpoise / radials required....and I doubt you have the room for them....but, you could try mounting the antenna at one end of the grab rail (I'd start trying the aft end), see what VSWR you get on 20m, and then (before experimenting with it on 20m), then try adding some wire to the other end (forward end) of the grab rail to get a total length of ~ 32' (tie that wire off with some thin line to your forward pulpit)....adjusting/trimming that wire (and your 40m hamstick whip-tip) to lowest VSWR on your preferred 40m freq...THEN...

Then, swap out to the 20m hamstick, check your VSWR....and, if it's bad (most probably will be), then add a ~ 16' long piece of wire to the antenna base, perhaps at an angle, and tie it off to your transom...adjusting/trimming that wire (and your 20m hamstick whip-tip) to lowest VSWR on your preferred 20m freq...

If you've taken your time and done things above precisely, you now have a 20m and 40m ground-plane antenna, mounted 12' - 15' above sea water and it should work well for you...you may need to use the '7300's internal tuner to touch things up and keep your transmitter happy, but you should have a fairly good antenna for 20m and 40m....

AND...if you want to get fancy, you can take your final counterpoise wire lengths, and stuff them inside some nice double-braided line, so when you have them rigged-up, nobody would ever guess they are part of an antenna! 


c)  Vince, notwithstanding the above workable solution....it is not something that I'd do....nope, I'd scarp the hamsticks, and go a different route.

A simple, easy-peasy solution is to not use "hamsticks", but rather use an AH-4 tuner and a marine HF whip antenna....and either using some "semi-tuned" counterpoise wires as "the other half" of your antenna, or more preferably, use a wide (low-impedence) copper strap from the tuner's "ground" lug to an underwater ground connection...   This would get you, 80m - 10m coverage (and probably 160m, as well), with no issues, easy-peasy....the AH-4 tuner is ~ $300 - $325 new, and a Shakespeare 393, 23' whip is ~ $300 - $325, new....so, this isn't a cheap solution, but it WILL work! 

{Of course, we are talking ham radio here....not HF Maritime Comms!  The reason I wish to stress this is, NO ham radios have DSC (Digital Selective Calling), and to raise any commercial ship or coast station (yes, even the USCG) you must use DSC on HF....this is part of the GMDSS, and has been with us now for 24 years!  So, it ain't new....but, just wanted everyone to be aware of this....as this is about ham radio on a boat...
If this was about maritime radio as well, then NO way could an IC-7300 work, and NO way would I ever recommend trying "hamsticks" and string counterpoise wires / radials! }


d)  I can highlight some other solutions, that are cheaper (and less versatile), but they will depend on you answering a few more questions / providing a bit more info....(perhaps a simple dipole or inverted-v, etc.?)


2)  Secondly, usually my very first piece of advice is to ask yourself a few questions, and let us know the answers....'cuz, there's a big difference in what I'd recommend for a guy wishing some casual ham rag-chewing on 20m and 40m, around the US, etc.....versus what I'd recommend for someone that wanted a reliable means of long-range comms, when offshore/in remote locales.....as well as differences between what can work well when anchored, versus what can also be easily used while underway.

So....do you desire to use this exclusively when anchored, or both underway and when at anchor?

And, what type of comms do you desire?  Casual ham rag-chewing across the US?  Or, serious operating?  Or, do you desire reliable long-range comms?

What is your budget?  What bridge clearances do you have to navigate thru?  How "handy" are you in doing a complete HF install?  Have you investigated and removed any RFI-producing devices from on-board?  Gosh, there are dozens more questions....but....

But, I went against my usual practice here and simply gave you some answers....probably not the best approach, but we'll see if this new "shoot-from-the-hip" / "never ask what the guy is actually trying to do" approach will be of any help?   (for many decades I've seen just about everyone else do this, and to be honest, I'm just about to give up on trying to give specific answers to folks....but...

But, if you desire some better / more detailed / elegant answers here, please answer all of these questions and provide much more detailed info. 



3)   Ignoring your VSWR issue for the moment....please understand that anything metallic can be used as an antenna....it's all a matter of degree!   And, what works best for one particular situation / application might not work well at all for another. 

So, before go off and deal with your "antenna" (and VSWR) issues, please take a moment to commit to memory a few "facts of life" in HF comms....I assume some/most of these you already know, but just to be sure:

----  Successful HF comms is all about RECEIVE S/N....(lowering your HF rec noise level, by ridding your boat of the many RFI-producing devices that surround us these days, is going to be the single most important aspect for you here)

---- Anything metallic can be used as an antenna (and antenna ground/counterpoise), it's just all a matter of degree

----  Use of the sea water for an antenna ground / counterpoise is excellent, and it provides a good wide-band counterpoise for MF and HF verticals....BUT, in order to maximize your antenna return currents, you must have the antenna feed-point (usually a remote tuner, such as the Icom AT-140, AT-130, AH-4, AH-2, or SGC, etc.) close to the sea water, and use a low-impedence connection from the antenna-feed-point/tuner ground lug to the sea water!   This is the most often misunderstood aspects of designing / installing HF antenna systems on small vessels such as ours! 


There is a lot more to all of this Vince, but I think I hit the high points for you....if not, please let me know....I'm just about 150 miles to your ESE, in SE Florida at the moment.

73 and Fair Winds,

John,  KA4WJA

s/v  Annie Laurie,  WDB6927,  MMSI# 366933110


Vince, et al,
Have a look here at these pages, where you'll see my boat, nav station, Atlantic crossings, etc. etc. etc...as well as a wealth of HF Maritime info in my Youtube video playlists!

https://www.qrz.com/db/KA4WJA

https://www.youtube.com/user/captainjohn49/playlists

https://jerodisys.com/C470/foto_bot.htm

https://www.instagram.com/p/CmYMlgAO3nD/?utm_source=ig_web_copy_link

https://www.instagram.com/p/CmYK5BvugAU/?utm_source=ig_web_copy_link

https://www.instagram.com/p/CmYLswWOpgu/?utm_source=ig_web_copy_link

[KI4VBR]

THANK YOU to everyone who has replied to my call for help.  I had some health problems that prevented me from replying to these messages, my apologies.  Lots of great advice as I would expect from E-Ham, TY.  I am thinking about purchasing an AH-4 antenna coupler and using a wire from my bridge to the front of my bow-rail with an insulator.  It would be an end-fed config around 42-43 feet in length, not sure if that would work.

I guess the other option is to use the bow rail, which is bonded to the boat and put the mount on the rail and see what kind of ground connection I get there.  I just the though of scratching up my stainless bow-rail with the mount, but the metal has to make contact, so I see no other way.  And yes, I agree that the tuner in the 730 is not up to the job of taking care of the mis-match in impedance.  The Alpha Moto looks like a good idea up on my fly-bridge hardtop, but not sure what to use for a ground.

Any additional comments are very welcomed and I thank everyone who took the time to share their knowledge with me.

TY,
Vince --... ...--

Here is a side picture of the boat:

[WA3SKN]

The marine environment can be rough, and you want things to work in the worst conditions... not just the sunny days!
I would suggest getting one of the old 18-20 ft fiberglass antennas for the 3.3 MHz band and a water resistant tuner like the SGC230.  You could have the tuner inside the cabin area and a short coax to the antenna... working it against the common ground of the boat.  That would be about as solid an arrangement as you could plan for.  Costs a bit more, but cost is relative here.  SGC originally designed just for the military, so they know what weather can be.

-Mike.

[KA4WJA]

Vince,
You're very welcome!
And, I do wish you a speedy recovery!

But, you keep referring to an Icom 730?  The old Icom IC-730 did not have a built-in tuner!
The newer Icom IC-7300 does...so, I assumed that you had an IC-7300?
But, you continue to write 730. 
So, I'm totally confused here.

Also, unfortunately you're asking more questions without answering mine / without providing more information as to what you wish to do with this system/set-up.  What is your application here?

Further, I don't know what an Alpha Moto is?
But, fyi...as I've been saying since the 1970's, "anything metallic can be used as an antenna....it's just a matter of degree on how well"
{I used a scrap piece of wire hanging from a flag halyard, plugged directly into the SO-239 antenna jack of a 10-watt QRP rig sitting on a cockpit cushion ---- and I had a pile-up going!  Many years ago, I used a mobile VHF/UHF scanner antenna on 10m, with a converted CB radio and worked > 50 DX stations in one afternoon!
One of my best friends loaded-up a 55-gallon drum and he used that as an antenna for months, talking all over the US, etc. etc. etc....
NONE of this means anything!}

I'd love to help you, and point you along the right course, but since I don't know what you want to do with this system, I would spend (waste) a good deal of time rambling away about things, at least half of which would be moot. 

So, if you could answer the questions I ask / tell us what your use / application is....maybe we could be of more help.
At the very least, where do you wish to communicate to?  what times of day?  what times of year?  on what bands for each of these previous questions?  do you have any specific / desired bands?  will this be needed while underway, or just at anchor?  have you done an RFI survey / test of the boat [away from the dock!]?  and, have you ridden your boat of RFI-producing devices?  what size is the boat?  where are you cruising?  do you need a system that will survive severe weather?  do you need it work during severe weather?  do you have any bridge clearance requirements?  etc. etc..

You see, Vince, anyone can post some oft-overheard recommendations, or some regurgitated advice (some even from decades ago), or even worse just some BS that they've picked up over time reading on the internet...but...
But, if they don't know what you're actually trying to do / what your application is, then the only way for their advice / recommendations to be accurate is, luck!  hi hi


 
Just so you don't think I'm being an a**, or dodging your query....

An AH-4 is a good choice...
And, a AH-4 fed wire (of ~ 40' - 45') running ~ quasi-horizontal, at a height of ~ 15', would be a very nice 40m antenna for "local"/"regional" (NVIS) comms, and "not bad" on 40m long-range comms as well....and although a bit "low" it would also be a fairly good 80m "local"/"regional" (NVIS) antenna!
It would also work pretty well on 20m and above....(although, with some lobes/directivity above 20m!  (if operations above 20m are desired, use a shorter horz span)
(fyi, although it might not "meet spec", you have a good chance of the AH-4 also tuning that wire on 160m)
BUT...

But, you've made no mention of an "antenna ground" / counterpoise?  (you know that's the other half of your antenna) 
Or, are considering making a horizontal doublet, feeding in the center with the AH-4?
Or, will you try to use the sea water for your antenna ground?  (if this is your plan...please note you cannot expect that to work well, if the AH-4 is mounted in the bridge / ~ 15 above the water.....although if you used 3" wide copper strap directly from the tuner down to an underwater grounding plate, it would be okay on 80m and probably 40m?)

My advice would be to mount the tuner down low in the hull...perhaps back in a lazarette? And, then you'd have a pretty short run (< 5') of 3" wide copper strap to an underwater grounding plate...and, you'd be good.
Of course, you'd need to figure out how to run your antenna wire....perhaps an "inverted-L" configuration?  Maybe use a fiberglass pole (fishing pole or Shakespeare antenna extension mast) going up 8' - 10' above the transom, to support the GTO-15 antenna wire (yes, you should be using GTO-15 wire here, NOT coax...NEVER use coax, no matter how short, here!), the antenna starts at the AH-4, and then run quasi-horizontal for about 40'....
That would make a nice all-band HF antenna, with both good low-band (80m and 40m) NVIS characteristics (and still have some good low-angle to the pattern as well), and also work well for long-distance 20m, 15m, etc...

BUT...
But, Vince, I'm not going to go on and on here....'cuz I have no idea what your application is....so, if you desire some more detailed recommends and/or more explanations of the ones I've already give, please answer all above questions. 


73,
John,  KA4WJA

P.S.  Just a quick clarifier here....yes the pseudo-Brewster angle of sea water is VERY LOW (~ 0.71 degrees on 20m....compared to 14.5 degrees for "average ground" on 20m), and yes while this does make for a significant advantage (in the far field) for vertical antennas over sea water, this does not apply to horizontal antennas! 
Also, while sea water isn't as good of RF conductor as copper (or aluminum), it is a whole lot better than fiberglass!  hi hi   And, many (including good 'ole Gordon West, and myself) have tested that a low-imp connection to the sea water, thereby using the sea water as your primary antenna ground / counterpoise, is vastly superior to "a few radials on the deck or below deck"! 
Of course, this is moot for steel or aluminum vessels as the hull / superstructure provides more than enough of an antenna ground!  (and then we all get the advantage of the VERY LOW pseudo-Brewster angle...which is actually 0.37 degress on 80m....ever wonder why 80m DX is so easy when at sea?)