SSB Grounding

[jvbarrac]

I'm new to the world of sailing and the cruisersforum alike. I bought an 82' Bayfield 29 a few months ago and have been preparing it for a year long Caribbean adventure. Our current project is single side band. We bought an Icom 710 and AT 130 tuner yesterday and have been considering setup options. We have been trying to decide whether we want to hoist a wire up the topping lift or buy a cheap 28 ft antenna. The man who sold us the 710 also has an antenna that he will sell on the cheap. We are certainly cost conscious cruisers and would prefer a cheap permanent solution like a whip (even if it will occasionally be in our way.) That being said, we were wondering if the experienced cruisers on the forum would have any other objections to it. In addition to an antenna, we are trying to figure out the grounding system. I was considering building a small contraption that would bolt to the transom and have a hinge joint that would allow it to be lowered into the water during transmission. I picture this thing hinging on the transom and lowering into the water about four feet or so. It may be made of aluminum tubing or pvc and will be covered in copper foil. An 8 gauge wire will connect this grounding device to the radio. Thanks in advance to anyone who comments, we really appreciate your suggestions and look forward to becoming apart of this awesome community.

[GordMay]

Greetings and welcome aboard the CF, jvbarrac.

[btrayfors]

Just about anything will "work" as the AT130 is capable of tuning a wet noodle.

However, to work well, you need a good antenna and ground system.

Antenna. A whip will work, of course, but a 23' whip on a 29' LOA vessel is a bit of the tail wagging the dog. I wouldn't do it. Better would be a traditional insulated backstay or an 'alternate backstay' if you can fit one on your boat. Lots of posts on these antennas. Basically, it's a random length of insulated s/s lifeline hoisted with a spare halyard (or a dedicated halyard) and tied off to one side of the pushpit. If your boom will clear this, and you don't have too much roach in the mainsail, then it's a very good, low cost solution which will last thru a hurricane. Mine has been thru 5 hurricanes over the past 20+ years.

RF ground. There are many solutions which will work. The "100 square feet of copper" and "tie everything together" impreachments which have dominated the SSB literature and instructions for over 20 years are just plain bunk. Any experienced ham knows there are lots of other solutions.

I have successfully used -- and often recommended -- a wide variety of RF grounds including, inter alia:

- aluminum toerails
- the pushpit/lifeline/pulpit complex
- s/s rub rails (like on Island Packet yachts)
- the steering and rudder post system
- large stainless steel swim platforms
- tuned 1/4-wave radials
- untuned radials
- wide copper strap to the nearest bronze thru-hull
- wide copper strap to embedded-in-the-hull RF ground systems
- "traditional" and unconventional grounding plates under the hull
and, of course,
- the KISS-SSB system.

All of these can work, and can work very well.

Of these, the KISS-SSB system is probably the easiest to implement and works very well. It costs $145 and while you can build a radial system for less cost in materials, if your time is worth anything IMHO you're further ahead buying one already built. Unless, of course, your boat has some ready solutions -- like the s/s rub rail on Island Packet yachts!

Every boat is different. I'd suggest that whatever you decide upon, you try it out with cheap materials first, before you build and install a "marinized" antenna and RF ground system.

Bill

[Highland Fling]

Originally Posted by btrayfors

Just about anything will "work" as the AT130 is capable of tuning a wet noodle.

However, to work well, you need a good antenna and ground system.

Antenna. A whip will work, of course, but a 23' whip on a 29' LOA vessel is a bit of the tail wagging the dog. I wouldn't do it. Better would be a traditional insulated backstay or an 'alternate backstay' if you can fit one on your boat. Lots of posts on these antennas. Basically, it's a random length of insulated s/s lifeline hoisted with a spare halyard (or a dedicated halyard) and tied off to one side of the pushpit. If your boom will clear this, and you don't have too much roach in the mainsail, then it's a very good, low cost solution which will last thru a hurricane. Mine has been thru 5 hurricanes over the past 20+ years.

RF ground. There are many solutions which will work. The "100 square feet of copper" and "tie everything together" impreachments which have dominated the SSB literature and instructions for over 20 years are just plain bunk. Any experienced ham knows there are lots of other solutions.

I have successfully used -- and often recommended -- a wide variety of RF grounds including, inter alia:

- aluminum toerails
- the pushpit/lifeline/pulpit complex
- s/s rub rails (like on Island Packet yachts)
- the steering and rudder post system
- large stainless steel swim platforms
- tuned 1/4-wave radials
- untuned radials
- wide copper strap to the nearest bronze thru-hull
- wide copper strap to embedded-in-the-hull RF ground systems
- "traditional" and unconventional grounding plates under the hull
and, of course,
- the KISS-SSB system.

All of these can work, and can work very well.

Of these, the KISS-SSB system is probably the easiest to implement and works very well. It costs $145 and while you can build a radial system for less cost in materials, if your time is worth anything IMHO you're further ahead buying one already built. Unless, of course, your boat has some ready solutions -- like the s/s rub rail on Island Packet yachts!

Every boat is different. I'd suggest that whatever you decide upon, you try it out with cheap materials first, before you build and install a "marinized" antenna and RF ground system.

Bill

OKIDOKI

I am just about to jump into the world of SSB and we have got ourselves a nice ICOM IC-M700PRO and an AT-130 and i am a SSB newbie AKA Numptie.

BEFORE spending any money on an insulated backstay and a KISS Ground I am going to try a rope antenna. I made one for a L42 cat many many years ago (real black majic suff then) and it worked fine much better than fine actually. BUT where to put that is the first issue. Now i know the GTO- 15 feed wire into an insulated backstay (option two for us - we have twin backstays) is 'better' stood off from the backstay until it gets to the clamp position. So could i also stand off a rope antenna going up one of the backstays? IF so could i not just use a long length of GTO-15 as my antenna stood off one of the backstays? Now we have an Ex Moorings Oceanis 461 which does not have (thank god) the teak capping to the top of the hull deck join but has an alloy capping of some 3" x 1/2" with frequent fixings that project nicely into the aft lazerette could i use this as my ground would this be a worthwhile experiment? OR ???

thanks in anticipation

kindest regards

David

[btrayfors]

David,I'm not familiar with the construction details of the Oceanis 461, but if I understand you correctly re: the "alloy capping" I would think that would definitely be worth a try, particularly if it's located along the deck where the toerail would normally be and if it's pretty long. It could serve as an elevated radial which makes for a very good RF ground.I'm not much of a fan of rope antennas, chiefly because I believe that an SSB antenna on a seagoing boat should be robust and able to stand up to the marine environment. The climate of the Caribbean is very harsh on copper antennas....I made a dipole from #14 stranded copper wire once about 40 years ago which lasted less than 2 weeks aboard!I'd either investigate the possibility of an "alternate backstay" antenna made of s/s lifeline or, maybe better, bite the bullet and get a good insulator (like the Hadyn fail-safe ones...about $300) installed a few feet from the top of one of your twin backstays and feed it belowdecks at the chainplate.Bill

[Seahunter]

Forget copper foil grounding. Install a KISS SSB counterpoise for your ground and a backstay antenna. A 27' SSB whip is too big to manage. We have a backstay and it works great; we also carry a 3 piece 27' SSB whip for emergency.

[jvbarrac]

Thanks for all of the quick responses! I guess we'll go with the KISS for the ground since it appears to be a simple, inexpensive solution. As for the antenna, is there any merit to the suggestion that installing the insulators will weaken the rig considerably. I've read posts on a few forums from cruisers who suggest that the added insulators provide more failure points to the backstay. Obviously this is true, any time you introduce more components into a system there are more possible points for failure but it doesn't seem as though it will be considerably weaker. Has anyone in here had a converted backstay fail at an insulator? Thanks again!!

[pdxsailordiver]

Originally Posted by jvbarrac

Thanks for all of the quick responses! I guess we'll go with the KISS for the ground since it appears to be a simple, inexpensive solution. As for the antenna, is there any merit to the suggestion that installing the insulators will weaken the rig considerably. I've read posts on a few forums from cruisers who suggest that the added insulators provide more failure points to the backstay. Obviously this is true, any time you introduce more components into a system there are more possible points for failure but it doesn't seem as though it will be considerably weaker. Has anyone in here had a converted backstay fail at an insulator? Thanks again!!

I used the rope topping lift to hoist a # 14 copper wire with insulators up between the split back stays. Terminated to radar tower. Ground is to stern pulpit, swim ladder and a wire to a through hull.
Before I did the ground I hooked a 20' piece of wire as ground and tossed over the stern. Tuned up and talked Oregon to NY. Then I finished. I have talked the world. Look up W7TPH Keep it simple.

[jvbarrac]

Its done, the backstay is at the riggers getting both insulators and the KISS is on its way! I plan on basing my wire runs (gauge vs. length) on a maximum current of 30 amps in the wire. Is this a safe estimate for the maximum current generated during transmission? Thanks again to everybody for your input.

[btrayfors]

No, the normal "10% drop" or "3% drop" figures are misleading for SSB installation.

While the peak draw will be 30A, it's very important to provide good clean power with almost no voltage drop to a SSB transceiver.

The rule is:

- for runs up to 20' wire length (one-way), use AWG6 cable
- over 20' and up to about 30' one-way, use AWG4 cable.

The cables should run from near the radio directly to the house batteries. You need fuses on both the positive and negative cables, located close to the house batteries. ABYC specification is that only 3 types of fuses are approved for direct connection to a house battery source: Class-T, ANL, and the new MRBF terminal fuses. I like ANLs or MRBFs.

Just did another install yesterday, using two MRBFs....one on the positive battery terminal and one on the negative shunt terminal. Used 30A fuses in each.

Near the radio, install a small terminal block, and lead the AWG6 or 4 wires to the block. It's convenient also to install a battery switch near the radio; I like the Blue Sea Systems #6006 which is inexpensive and very robust. It can be installed as a surface mount or a recessed mount switch, and makes a convenient way to shut power on/off to the radio, modem, SWR meter light, etc.

In addition to ensuring a very clean dedicated power source for the SSB, the reason for going directly to the house batteries is to help reduce radio frequency interference (RFI), both to the radio from other onboard equipment and instruments and to these from the radio.

We used a KISS-SSB ground system also, which with the insulated backstay was very easy to tune with the AT-130 coupler. First call from near Annapolis was answered by a boat in Bermuda -- loud and clear on 12359 kHz.

Bill

[roverhi]

I sailed to SoPac with a backstay insulated with ceramic insulators and wire held to gether with nico press fitting. Worked fine for more than 10,000 miles of cruising. Have a couple of Norsman insulators on the backstay of my current boat. Has done a TransPac without a problem. The insulators do add additional failure points to a stay but wouldn't worry about it. The Norseman fittings, StaLok also, are extremely reliable, easy to do by you, and virtually trouble free. I've sailed many many thousands of miles with Norseman terminals over many years without an issue.

The ground for a radio is not the same as a ground for an electrical circuit. It doesn't have to touch the water or the ground. I've used two 30+' copper strips along each side of the deck for my ground plane. The KISS system seems a lot less of a hassle and it's definitely cheaper. Copper strapping is damned expensive.

[btrayfors]

The Hadyn insulators are expensive, but are fail-safe. They're the ones I use when I need to install an insulator in a shroud or backstay.

Also, depending on your setup you might be able to get away with just a single insulator a few feet from the top of the mast. Feed it belowdecks at the chain plates. If you're worried about RF burns (likelihood is often exaggerated), just put some PVC around the bottom of the backstay.

Bill

[Seahunter]

You could also use a rope antenna or split lead as there are a number of each on the market or you could build your own. If maintained a backstay antenna will not fail as the fittings are stronger than the rigging in most cases.

[Seahunter]

Use antenna coax. Make sure the ground connection between the tuner and the radio are disconnected but that the each unit is grounded to the battery(ies); especially when using the KISS. All - battery grounds connections should be bonded to a dive plate of some kind. The complete directions can be viewed here: Customer Testimonials or read the ICOM manual.

[Maxs]

Nice thread!! Could the ground wire from a digital radar antenna also connected to the KISS-SSB system???