Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 05-03-2012, 11:21   #1
Registered User

Join Date: Mar 2010
Posts: 42
Proper Length of Antenna and Other SSB Questions

We own a Morgan Out Island ketch. On board we have an Icom 700 Pro radio; SGC sg-230 tuner; and SCS Pactor Modem. The antenna is rigged on the mizzen port side shroud. That shroud starts at the top of the mizzen mast, and approximately half way down, travels through an aluminum spreader tip, then down to a turnbuckle on the port side of the boat. Distance from the top insulator to the bottom insulater is approximately 29 feet 2 inches. The top insulator is about 1-2 feet from the mast itself.

In 2004-2005 my wife and I went cruising. During that time, we were able to send and receive emails - using Sailmail - with moderate success. Use of the SSB, however, was limited. We could never seem to be able to reach out very far to communicate. Since that time, I have obtained my General Class license, and so want to be able to communicate further than before, to use Sailmail and Airmail, and to communicate on the Ham bands, which my radio is equiped to do.

We are going cruising again in November - yeaaa - and want to make sure we are able to communicate more effectively. I have read most if not all the posts on this site already dealing with these issues, but still have some questions particular to our boat:

1. Is the 29'-2" length of wire between insulators, long enough to provide a good antenna - my alternative is to switch to the main backstay (one of two) that are 56 feet long;
2. Assuming that I have made sure there is no direct connection with the aluminum spreader and the antenna wire - I have the shroud wrapped with tape at the spreader tip - is this bend in the antenna problematic?
3. I previously had the Icom connected to the radio using a 3 inch strip of copper strap, which was attached to the grounding lug of the tuner. Was that correct? Recent posts suggest connecting with coax?
4. Since all the prior copper strapping I laid for a counterpoise has rotted away, I am opting to buy the Kiss counterpoise and use it as the counterpoise. I know some have argued it is too expensive - but it also appears to be simple, quick and that it works.
5. On what wires do I place ferrites? On the power connection from radio to tuner? On the ground connection from radio to tuner? Should I attach ferrites at all? Is it simply a matter of putting them on, as they don't hurt, and may help? If so, what type - do they have model numbers, or other identifying numbers/values?

Thanks for your responses in advance. George
__________________

__________________
gchabs is offline   Reply With Quote
Old 05-03-2012, 11:48   #2
Moderator
 
Paul Elliott's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 3,880
Images: 4
Re: Proper length of antenna and other SSB questions

29' is a reasonable antenna length. Your true length is longer, as it includes the feed wire from the tuner. Where is your tuner located? The ground strap should run from the tuner to your ground system (the KISS ground reportedly works reasonably well). You don't need heavy grounding between the radio and the tuner; the coax cable is carrying the signal. Ferrites at the tuner control cable wouldn't be a bad idea, and some people have them at the tuner on the coax (I don't, but they shouldn't hurt.)

A bend at the spreader is a non-issue, but the insulation needs to be good. There's high voltage up there, and probably chafe.

I prefer the backstay to a shroud, as the backstay is more isolated from the rest of the rigging. Honestly though, I have no idea if this will make a significant difference.

For SSB frequencies I use Fair-Rite #0431164181, which is a 31-material clamp-on core. I get them from Mouser Electronics. There are other ferrite cores that people use specifically for coax isolation purposes, and I hope someone here can fill us in on those.
__________________

__________________
Paul Elliott, S/V VALIS - Pacific Seacraft 44 #16 - Friday Harbor, WA
www.sailvalis.com
Paul Elliott is offline   Reply With Quote
Old 05-03-2012, 12:13   #3
Senior Cruiser

Cruisers Forum Supporter

Join Date: Jul 2006
Location: Chesapeake Region and Maine
Boat: 42' Bob Perry sloop
Posts: 4,038
Images: 4
Re: Proper length of antenna and other SSB questions

+1 on what Paul said.

I, too would prefer one of the backstays over the shroud, but the shroud will work OK if you insulate well at the spreader tip.

The shorter shroud length will tend to favor the higher bands, while a backstay would tend to favor the lower bands. But both should tune all bands.

Yes, the KISS is probably the way to go...very easy to install and -- all in all -- a less expensive and troublesome solution in your case.

An important consideration not mentioned above is how to power the radio. The 700PRO is a 150-watt output radio with no provision for lower power. It will need 30 amps or more on voice peaks and for data modes. The proper way to get power to the radio is to use AWG6 cable for runs up to 20' and AWG4 cable for longer runs. Put a 40A ANL fuse in both the positive and the negative cables located close to the house batteries. Alternatively, use 30A MRBF terminal fuses connected directly to the terminals or the bus.

While RG8X coax between the radio and the tuner will work OK, I find it's better to use RG-213, RG-214 or LMR400 (or equivalent) both because of their strength and their better shielding. This helps to prevent RFI from the radio into other things on the boat, and from other things into the receiver. Ferrites aren't a bad idea; sometimes they help.

Congratulations on the General. Don't know where you're located, but if it's on the East Coast somewhere between Nova Scotia and the Caribbean I hope you'll check into the WaterWay Net on 7268kHz LSB at 0745-0830 Eastern Time daily.

Good luck,

Bill
WA6CCA
__________________
btrayfors is offline   Reply With Quote
Old 06-03-2012, 11:17   #4
Registered User

Join Date: Mar 2010
Posts: 42
Re: Proper length of antenna and other SSB questions

Paul and Bill: Thanks very much for the information.

As for Paul's question, the tuner is located approximately 3 feet forward, and 7 feet below the point where I attach the feed wire from the tuner to the antenna. The tuner is housed on a bulkhead adjacent to an inverter - I do not run the inverter when operating the SSB - and about 6 feet aft of the SSB and VHF. My true antenna length, would therefore be closer to 39 feet. As for Bill’s invitation, I am located just west of Deltaville Virginia, on the Rappahannock River, and hope to participate in the Net as soon as I get my rig working.

Your comments have raised a couple more questions. Paul wrote “the coax cable is carrying the signal” and “Ferrites at the tuner control cable wouldn't be a bad idea, and some people have them at the tuner on the coax.” Bill wrote “RG8X coax between the radio and the tuner will work OK, I find it's better to use RG-213, RG-214 or LMR400 to coax, and various types.”

I have reviewed the SG -230 Tuner manual and the 700 Pro manual - and what I remember about my setup appears to match what the manuals indicate - the tuner has a wire with a PL-259 connector on the radio end, that goes from the bottom of the tuner to the 700 Pro and connects in back of the radio. Call that cable #1. On the bottom of the tuner, there is a lug that I believe I would attach to the Kiss (counterpoise) and which I previously connected by way of copper strapping, to the engine, a steel plate in the aft bilge, the keel. Call that cable #2; and finally, a lug on top of the tuner to which I would attach GTO-15 wire and then attach the other end of that GTO 15 wire to the shroud above the insulator. Call that cable #3. There are no other wires emanating from the tuner.

My questions are what wires, coax, etc. are you gentlemen referring to in your posts? It sounds like I am missing some connection between the radio and the tuner? At one time as I mentioned in my initial post, I had attached a 3” wide piece of copper strapping from the back of the radio to the ground lug of the tuner. Call that cable #4. Is that what should be coax? Am I missing something very fundamental?

Once again thanks very much for your insights. George
__________________
gchabs is offline   Reply With Quote
Old 06-03-2012, 11:37   #5
Registered User

Join Date: Dec 2010
Location: W Carib
Boat: Wildcat 35, Hobie 33
Posts: 7,957
Re: Proper length of antenna and other SSB questions

Assuming that the system is all set-up and connected properly, the most common factor I have seen causing poor performance in SSB rigs is grounding. Review your grounding configuration carefully.
__________________
belizesailor is offline   Reply With Quote
Old 06-03-2012, 13:34   #6
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,055
Re: Proper length of antenna and other SSB questions

george-
"attach the other end of that GTO 15 wire to the shroud above the insulator. "
This indicates you are using the shroud cable itself as the antenna wire, yes? And that shroud goes through an aluminum spreader tip, which in turn is making some kind of contact, so the spreader and now the mast--which is presumably grounded at the keel step and also attached to all the rest of your rigging--is now part of your antenna.

That could explain a number of things, since it would mean ALL the rigging is now affecting your antenna performance. Even if that spreader tip is insulated, you might want to consider running a length of GTO-15 all the way up, using stand-offs or just zip-tying, to isolate the antenna from the rigging somewhat better.

The KISS counterposie certainly scores for plug-n-play convenience but the autopsy that was posted says it is just a batch of wires cut to resonant lengths. You could easily do that with buying one spool of wire and a tape measure. You know, keep the snake oil out of the bilge water too.
__________________
hellosailor is offline   Reply With Quote
Old 06-03-2012, 14:07   #7
Senior Cruiser

Cruisers Forum Supporter

Join Date: Jul 2006
Location: Chesapeake Region and Maine
Boat: 42' Bob Perry sloop
Posts: 4,038
Images: 4
Re: Proper length of antenna and other SSB questions

George,

Yes, according to your description you are indeed missing something: the two wires to the tuner which provide 12VDC @ about 1.5A.

Most SG-230's were shipped with a single cable exiting the tuner: it was a multipurpose cable consisting of:

1. thin coax which actually carries the RF signal from the radio to the tuner; and

2. four additional wires wrapped around the coax, two of which (red and black) are necessary in order to provide 12VDC to the tuner, plus two others which aren't really necessary in most installations (they are intended for an accessory which allows for reset of the tuner and which gives a visual indication of tune).

The tuner will not work without the 12V connection. Look carefully...it's gotta be there somewhere.

So, the final installation of the SG-230 tuner should consist of:

1. GTO-15 single-conductor high-tension cable from the tuner's antenna standoff to the shroud or backstay antenna;

2. Coax cable from the tuner to the M700Pro radio;

3. A 12V DC connection, fused, consisting of a red wire (pos.) and a black wire (neg.); and

4. The KISS-SSB radial ground system connected to the ground lug on the tuner.

Nothing else in the way of connections is necessary or desirable.

You do NOT need to run a separate grounding cable from the tuner to the radio, nor do you need a grounding cable on the radio. These can create undesirable ground loops.

Ferrites can be used if desired or needed; wrap them about both the power line and the coax at both ends.

Bill
__________________
btrayfors is offline   Reply With Quote
Old 06-03-2012, 14:21   #8
Registered User
 
PamlicoTraveler's Avatar

Join Date: Aug 2008
Location: Depends
Boat: SB 43' Cutter
Posts: 679
Images: 13
Re: Proper length of antenna and other SSB questions

Quote:
Originally Posted by btrayfors View Post
The tuner will not work without the 12V connection. Look carefully...it's gotta be there somewhere.

So, the final installation of the SG-230 tuner should consist of:

1. GTO-15 single-conductor high-tension cable from the tuner's antenna standoff to the shroud or backstay antenna;

2. Coax cable from the tuner to the M700Pro radio;

3. A 12V DC connection, fused, consisting of a red wire (pos.) and a black wire (neg.); and

4. The KISS-SSB radial ground system connected to the ground lug on the tuner.

Nothing else in the way of connections is necessary or desirable.

You do NOT need to run a separate grounding cable from the tuner to the radio, nor do you need a grounding cable on the radio. These can create undesirable ground loops.

Ferrites can be used if desired or needed; wrap them about both the power line and the coax at both ends.

Bill
Hey Bill.... His SG 230 might have the wire like mine where the power and ground for the tuner are inside the "coax" cable.
__________________
The next best thing to playing and winning
is playing and losing ...
[I]
PamlicoTraveler is offline   Reply With Quote
Old 06-03-2012, 15:53   #9
Senior Cruiser

Cruisers Forum Supporter

Join Date: Jul 2006
Location: Chesapeake Region and Maine
Boat: 42' Bob Perry sloop
Posts: 4,038
Images: 4
Re: Proper length of antenna and other SSB questions

Quote:
Originally Posted by PamlicoTraveler View Post
Hey Bill.... His SG 230 might have the wire like mine where the power and ground for the tuner are inside the "coax" cable.
Yes. That's what I was trying to say.

I actually have six of the cables here. Let me try to describe them better.

The cable which exits the tuner has an outer rubber covering and is 11/32 inches in diameter. The coax itself is also rubber covered, lives inside this outer covering, and is about 7/32 inches in diameter.

Sandwiched between the two rubber coverings are four wires: red, black, red/black striped, and black/white striped.

The only ones you care about -- which are absolutely critical to the functioning of the tuner -- are the solid red and black wires. Red for +12VDC and black for -12VDC.

Bill
__________________
btrayfors is offline   Reply With Quote
Old 06-03-2012, 21:08   #10
Moderator
 
Paul Elliott's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 3,880
Images: 4
Re: Proper length of antenna and other SSB questions

I'm not really familiar with the SG tuner -- what triggers the autotune? Is it monitoring the SWR and signal level? I mentioned control wires, but it sounds like there aren't any.
__________________
Paul Elliott, S/V VALIS - Pacific Seacraft 44 #16 - Friday Harbor, WA
www.sailvalis.com
Paul Elliott is offline   Reply With Quote
Old 06-03-2012, 21:54   #11
Registered User
 
Jon Hacking's Avatar

Join Date: Sep 2010
Location: Currently cruising Southern Indonesia, heading for peninsular Malaysia
Boat: Wauquiez 45' (now 48') catamaran
Posts: 523
Send a message via Skype™ to Jon Hacking
Re: Proper length of antenna and other SSB questions

I'm not a big fan of using my rigging as an antenna, & as HelloSailor mentioned, the voltages get very high & may very well be shorting over to make your whole mizzen radiate.

I would suggest running your antenna wire from your tuner to a point a bit forward of your mizzen & then up towards the top of your mizzen. Better yet would be to run the antenna wire to the top of the main-mast, or even from the deck to near the top of the mizzen, & then to the top of the main, like a triatic stay. This should keep it clear of any sails & get it clear of the rest of your rigging so it can radiate well. Use insulators to keep it from getting too close to any other rigging bits like your mizzen or main masts (I just use a bit of 1/8" parachute cord as my insulators & it works just fine).
__________________
-- Jon Hacking s/v Ocelot
Jon Hacking is offline   Reply With Quote
Old 06-03-2012, 22:09   #12
Marine Service Provider
 
Scott Berg's Avatar

Join Date: Jul 2011
Location: Aboard
Boat: Seaton 60' Ketch
Posts: 959
Quote:
Originally Posted by Paul Elliott
I'm not really familiar with the SG tuner -- what triggers the autotune? Is it monitoring the SWR and signal level? I mentioned control wires, but it sounds like there aren't any.
It has a freq counter and activates on RF

SB
__________________
Scott Berg
WAØLSS
SV CHARDONNAY
Scott Berg is offline   Reply With Quote
Old 07-03-2012, 12:15   #13
Registered User

Join Date: Mar 2010
Posts: 42
Re: Proper Length of Antenna and Other SSB Questions

Thanks to all who have responded. I have looked at the SGC SG-230 tuner manual and I believe Bill and PamlicoTraveller are correct. The diagram of the wiring on the tuner reveals that the tuner is connected to the radio by a single cable (cable #1 in my earlier post) which connects with a PL-259 plug. That wire is made up of four smaller wires, with the following descriptions provided by SGC, black (ground); red (+12vdc); red/white (SmartLock control line); black/white (Remote Tuned Indicator). Since the cable uses a PL-259 plug, I presume that these four wires are wrapped in a coax sheath. So, based on Bill’s description of the wire he has examined, I believe I have the wiring necessary to connect the tuner to the radio.
With that in mind, I will assume that by simply plugging in the PL-259 plug into the back of the radio, that cable #1 provides power and signal to the tuner. If that is wrong, please advise. I shall also place ferrites on cable #1, at the radio and at the tuner ends. I shall not provide any other grounding for the radio. In light of some of the comments re: the possible problems with my antenna passing through the spreader tips, I shall make sure that the insulation at the spreader tip is good. I shall then test what type of signal I am sending/receiving by using that setup as the antenna. Then, I will disconnect the GTO-15 wire and connect it to a single wire (AWG 12 or 14) hauled to the top of the main mast on a halyard, and test the reception/sending using that as my antenna. Depending on results, I may opt to switch the insulators to the main backstay and use that as the antenna. As far as the Kiss counterpoise is concerned, I will connect it to the ground lug on the tuner. I appreciate the feedback that this product may be smoke and mirrors, but, I am convinced that it appears to work for a lot of people, and in the grand scheme of things $140 is worth my time and reduced frustration.
Again, thanks to all for all the assistance. Once I get it all set up, I will advise of my results. George
__________________
gchabs is offline   Reply With Quote
Old 07-03-2012, 12:37   #14
Senior Cruiser

Cruisers Forum Supporter

Join Date: Jul 2006
Location: Chesapeake Region and Maine
Boat: 42' Bob Perry sloop
Posts: 4,038
Images: 4
Re: Proper Length of Antenna and Other SSB Questions

Quote:
Originally Posted by gchabs View Post
.....
With that in mind, I will assume that by simply plugging in the PL-259 plug into the back of the radio, that cable #1 provides power and signal to the tuner. If that is wrong, please advise.......

NO, GEORGE, THAT IS NOT CORRECT.


The larger cable as I described contains two very different things:

1. The coax cable, with it's own rubber covering and with a PL-259 connector on the end; and

2. Four small wires, two of which are of critical importance as they provide 12VDC to the tuner. These wires are located under the outer rubber covering and outside of the rubber covering of the coax itself.

I don't like this arrangement, and sometimes modify the SG-230 connections myself, but this is what SGC has chosen to do. They have bundled two things together.

The PL-259 UHF connector connects to the radio, either directly or via a longer coax jumper if that is necessary.

IN ADDITION, it is necessary to connect the solid red wire and the solid black wire to a 12VDC source.....on your panel or elsewhere. These wires carry very little current, but they are critical whenever the tuner is in use. Put a 2A fuse in the red wire.

Forget about the other two wires; tape them off.

Bill
__________________
btrayfors is offline   Reply With Quote
Old 07-03-2012, 12:46   #15
Moderator
 
Paul Elliott's Avatar

Cruisers Forum Supporter

Join Date: Sep 2006
Posts: 3,880
Images: 4
Re: Proper Length of Antenna and Other SSB Questions

(I see that Bill already answered your question while I was composing this. As is usually the case, we agree.)

OK, I'm looking at the SG-230 manual now.

The cable bundle from the tuner to the radio contains a coax cable with PL-259 connector -- this goes to your transceiver's "Antenna Connector".

The PL-259 connector is *only* carrying the radio signal.

Also in the cable are black, red, red/white, and black/white wires. You need to find these and connect at least the black wire to your D.C. ground, and the red wire to a fused or breakered +12V power source.

The red/white and black/white wires are for optional features, and it sounds like you can leave these unconnected (I would wrap the ends in tape).
__________________

__________________
Paul Elliott, S/V VALIS - Pacific Seacraft 44 #16 - Friday Harbor, WA
www.sailvalis.com
Paul Elliott is offline   Reply With Quote
Reply

Tags
antenna, ssb

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
What Brand of PFD / Harness Do You Prefer ? Snore Deck hardware: Rigging, Sails & Hoisting 21 01-05-2012 08:02
Show Us a Bird's Eye View of Your Digs deckofficer Off Topic Forum 48 15-03-2012 20:52
Proper Length of Antenna and Other SSB Questions gchabs Marine Electronics 25 09-03-2012 14:51
Toe Rail and Railing Gnarl Construction, Maintenance & Refit 6 09-03-2012 12:11
For Sale: Paper Charts of the Caribbean Tristan Classifieds Archive 15 06-03-2012 16:44



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 22:58.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.