Singlehanded Sailing off the Skeleton Coast (Namibia) & SSB Problems
Jeanne Socrates has been sailing single-handed for about five years now on her yacht "Nereida", a Najad 361. She is currently 12 months into her first solo circumnavigation, having left Mexico in March of last year. Jeanne has now rounded the Cape of Good Hope, and is sailing north along the African continent, before heading across the Atlantic ocean to Trinidad.
Jeanne warns sailors to keep a good watch off the Skeleton Coast in Namibia. She sent in this report from aboard her yacht Nereida:
As usual over the afternoon & evening, the wind had got up strongly but I was surprised just how strong it was as I went to raise the mains'l outside the harbour entrance channel near Pt Diaz - a good F6-7, around 27-28 knots, from the SW, which became over 30kn apparent when I used the motor, as I had to, to keep us heading into wind to raise the sail (triple-reefed main & correspondingly tiny genoa!).
As I headed out further, making 5-6 knots in 3m seas, the fog I was expecting a short distance out was more murky mistiness in the failing light. I knew a diamond dredger was stationed to the NW of Luderitz Hbr & reckoned I could see it in the distance but my course (300T) seemed fine to avoid it. I heard 'Discoverer' calling a boat on VHF getting close to its anchor lines & wondered where 'Discoverer' was exactly.... someone came on the VHF to say the boat in question "had no engine" - which struck me as odd. I assumed this was all taking place further down the coast somewhere... & went down below, with the boat going well in the strong conditions, to make a log entry.
Suddenly I heard the radio blare into life: "Sailing ship - you are about to foul in my anchor lines - turn south IMMEDIATELY!"....It could only be addressed to me since I was the only sailing boat around.... I rushed up on deck & dead ahead, too close for comfort, I could see four long lines splayed out from the ship - THIS must be 'Discoverer' (NOT displaying a signal on my AIS unit, for whatever reason, which would have warned me - unlike another ship which I had just been calling, thinking it was them, to confirm they were anchored & that I would be clearing their lines OK... ). Clearly, in the strong wind, our leeway was sufficient to have caused the drift towards them. Also, the problem was that the lines are VERY long and angled very shallowly - so a really good distance needs to be kept from these anchored diamond dredger ships.
I swung the boat around to the south, but the wind was so strong, & almost from that direction, that now we lost way & actually couldn't make the tack.... as we drifted closer, I started the engine (that's when you're relieved you kept up the regular maintenance - when it works in an emergency...!). It helped us escape, but heading "two km south & then 2 km west" as I was instructed just wasn't happening..... I had to tack like mad, with motor well-revved up, to make any headway away from those lines..... Going north wasn't an option because of the orientation of the lines. After each tack, either we ended up headed ESE or due W. After what seemed like an age, I nipped down to see where they were on the AIS display (he'd clearly turned on his unit after a comment of mine) ... he was 0.9 ml due east of me. I called him up to ask if that was far enough.... "no, you might foul the other lines - keep heading south & then west & then you're free to head wherever you like!" came the reply.
I was drenched from the spray as waves hit us - thank goodness I'd put on my jacket & hat for raising the mains'l earlier....! More quick tacking for what seemed like an eternity.... but finally we were OK & the ship's lights faded in the gloom astern, as he wished me well on my journey, saying "All's well that ends well!"
- Jeanne Socrates
25-53.62S / 013-34.63E
-- About Jeanne's Travels (from her blog) --
My proposed circumnavigation:
One major reason for wanting to do a solo circumnavigation is probably the challenge of all that it involves. I enjoy being at sea, as well as meeting people & seeing places on shore, but time doesn't stand still (& bodies don't get younger!) so I feel that now is the time for me to 'sail around the world' in a reasonably short time, as a sailing challenge, rather as the sailors of olden times did, rather than continuing my present slow cruising & taking a lot more years to get around (that can always come later). I'm feeling quite excited at the prospect of it all ...
Preparing "Nereida" in San Diego took quite a time, but I finally sailed down to Ensenada mid-February to complete Mexican check-in formalities and then headed towards Zihuatanejo - where their Guitar Festival finished 18th March. By the end of March, I was well on my way to the Marquesas after fresh food provisioning from the local market.
In planning my route, I have to avoid the cyclone season in the southern hemisphere - November/December to March/April. My route now looks something like this, having left Zihuatanejo on Monday 26th March 2007 (as expected, time is dictating that some places in Polynesia are having to be passed by):
S. Pacific: Marquesas (arrived April 19th) - Rangiroa (Tuamotus) - Tahiti - Bora Bora - Nuie - Tonga - Fiji - Vanuatu (leave Espiritu Santo for Australia by 1st July) - Cairns - Darwin (by early August) to Indonesia (Bali/Lombok) via Indian Ocean (Cocos Keeling - Rodriguez - Mauritius - Reunion). Reach S. Africa by early-mid November, leave Cape Town early January '08, then via S. Atlantic & Caribbean to Panama & back into the Pacific.
Clearly, weather is the main concern and any planning has to be flexible - but with good weather information (via SSB & VHF radio and onboard barometer), it should be possible to have sufficient advance warning to stay safe.
-- About the Yacht Nereida --
Nereida is a Najad 361, hull number 93, built in 1997 by Najadvarvet at Henan on the island of Orust in Sweden. She is named after the 'nereids' of ancient Greek mythology who were the 'handmaidens of Poseidon'.
CLICK HERE TO READ ABOUT JEANNE'S NEXT STOP IN ST. HELENA
You can visit Jeanne's website at: http://svnereida.com/
-- About the Skeleton Coast - Namibia --
The Skeleton Coast is the northern part of the Atlantic Ocean coast of Namibia and south of Angola from the Kunene River south to the Swakop River, although it is sometimes used to describe the entire Namibia Desert coast. The Bushmen of the Namibian interior called it the region "The Land God Made in Anger", while Portuguese sailors once referred to it as "The Gates of Hell".
On the coast the upwelling of the cold Benguela current gives rise to dense ocean fogs (called "cassimbo" by the Angolans) for much of the year. The winds blow from land to sea, and rain fall rarely exceeds .39 inches annually. There is a constant, heavy surf on the beaches. The coast is generally flat, occasionally relieved by rocky outcrops. The southern section consists of gravel plains, while north of Terrace Bay the landscape is dominated by high sand dunes.
The coast is named for the bleached whale and seal bones which covered the shore when the whaling industry was still active, as well as the skeletal shipwrecks caused by rocks offshore in the fog. More than a thousand boats of various sizes and areas litter the coast. Notable wrecks in the region include the Eduard Bohlen, the Otavi, the Dunedin Star, and Tong Taw.
Submitted By YachtPals on 03 Mar
Skeleton Coast, Africa, Namibia, Jeanne, Nereida, yachts, boats, sailboats, sailing, cruising
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SSB help needed
Jeanne emailed that she is having trouble with her SSB.
Here is her trouble (quote from Jeanne's email via sat. phone):
"I've been trying to sort out where in my radio system I should add a new line isolator and ferrite chokes I had sent out to me in S. Africa. I'm trying to get rid of a RFI (radio frequency interference) problem in the SSB radio system which is also affecting the computer & Pactor modem used for emailing via radio.
At present, I'm still having major problems:
1) PC often 'hangs up' (telling me, "ERROR: Communications with the PTC-IIpro have been lost.") when trying to connect, especially on 12 & 14 MHz - often JUST as I'm actually getting connected;
2) other times, PC doesn't respond to a successful connection being made by the radio/modem & sits there, still saying it's calling the station ... then I have to close the Airmail program down & re-start it.... all very frustrating, as well as time- & power-consuming.
Then, if battery power is below about 12.4V, the call attempt is often unsuccessful anyway, with the Pactor modem showing its anger by flashing all possible lights at me as it refuses to make the call attempt. Then I have to close the Terminal window on the PC down & open it up again & try a different frequency, after switching off & on the radio.... It all gets very convoluted & annoying...."
Can anybody figure out what her problem might be?
Thanks for the help
Problems with SSB
First, I have to express my jealousy and admiration for what Jeanne is doing. One of my dream destinations is St. Helena. Not entirely sure why, but I want to visit before they build the airport.....
On to the question at hand. Three years ago I singlehanded from the NYC area to Bermuda and back. Part of the prep for my Flicka 20 was to install an SSB system. As tiny as my boat is, my signal reports from Herb (weather and routing guru based near Toronto) were stronger than any of the other boats in St. George. That's not to brag, but the installation is nearly perfect. The one fly in the ointment I'll get to later..
My radio is the ICOM M802 with an automatic antenna tuner and the same Pactor modem. In general, the most critical component of a high frequency radio installation is the ground connection. I used two Dynaplates, which are approximately 2"x12", made of bronze in such a way that electrically they appear to be many times their physical size. The other possibility is to set up a capacitative ground by laying copper mesh, tape, whatever you can find that's conductive and can be laid directly on the inside of the hull. That's a lot of work.. Finally, and I'm skipping an awful lot, you MUST make your ground connections from your radio with heavy copper tape. Radio frequency energy travels on the surface of a conductor, so copper tape is far more efficient than plain wire. A bad ground or ground connection will result in RF bouncing around the equipment with unpredictable results. Also, RF burns are painful!
The power drop-off problem may be caused by inadequate feed to the rig. The power leads, both positive and negative, should not be taken from the breaker panel, but directly from the battery, using, I would say, 8 guage wire at a minimum and with an inline fuse on the positive wire. All radios are different, but I will tell you that my ICOM will fail to function when the voltage drops a bit. Also, on the M802, the modem is powered through the radio, so a voltage drop in the radio will also cause the modem to stop working. I'm going to guess that the radio is wired to the panel, causing a voltage drop in the radio that would not show on the panel's meter. As a test, try using the lowest power setting the radio has and see if the symptoms persist.
Ferrites should be added to data lines from the modem and you might as well stick one on the data cable that goes to the computer.
Oh, the one fly? The GPS input to my radar/plotter I use also for the M802 so that position information is always available for the DCS system. Chirps get into the audio and they're loud enough that I have to disconnect the GPS for weak signals. A minor inconvenience and I'm convinced that rerouting the ground from the plotter will resolve the issue. We'll see...........
I hope this helps and please advise if it doesn't. We'll figure it out!
Steve McWherter
SSB Problems
Best to chokes on both ends of each cable running between radio, computer & modem. Chokes are cheap - use the shotgun approach.
SSB Problems
I had a similar problem with my PACTOR/HAM rig as you describe in your last paragraph - i.e., PACTOR modem flashing all possible lights and refusing to participate when attempting to call. This occurred even with full batteries. I found that if I would turn the equipment on and then let it sit and "warm up" for a couple of minutes before calling, the problem would not occur. i asked a couple of gurus, including Jim Corenman, about this phenomena and no one had a good explanation for it. Good Luck. Rich
SSB Problems
I had a USB/serial port converter box between my computer (which only has USB ports) and my PACTOR modum (which only has RS-232 ports on it). Many times when I transmitted the converter box would shut-off & torpedo my transmission. I fixed the problem by deep-six'ing the cheapo Belkin converter box & bought a high quality Edgeport converter. I even paid a few bucks extra and got the model in the aluminum casing for better shielding. Never had a problem since!
RFI
Alex KR6G Kenwood, Vertex, Midland 2 way sales service Dish Net work, Hughes internet sales service Just here to try and help out some sailors with radio satellite problems.
Just some generial comments, then maybe you can send me some detailed information on your equipment, with model # etc.
First off I know nothing about sailing around the point, yet around the world, my experience is with military ships.
I have been in the satellite and 2 way radio field for over 45 years, so hope we can figure out what your problems are.
Oh I think your CRAZY !!! Ok off we go trying to fix your problem. By the way I was in law enforcement and then communiations and I would take a lady in a heart beat over any guy. Girls are smart. !
I would like a run down of your equipment if possible.
Try and keep the computer cables and modem cables as far apart from the rf cables as possible, this includes keeping any out side antenna's as far a part as possible, even to the point of bringing the cables in different sides of the room.
Get as good as ground as you can on all the equipment, if a ground is not possible then use the neg side of the battery for the ground.
Keep the power output as low as possible on your transmitter. IN most case keeping the antenna's away from each other does the most good.
I have to attend a meeting all day saturday leaving at 5 am and not getting home until after 7 pm, then Sunday off again doing the same thing, so will try and check e mail when I can. I'm sure there will lots of folks with ideals and we all hope to cure your problems with you.
Good luck---Your still crazy. !!!
Alex kr6g
LaNell ke6lom
SSB
All leads (wires) entering the computer and entering the modem are susceptible to picking up stray RF from the antenna. So also is the microphone lead to the radio.
If by chokes she means ferrite half-rings with plastic clips to hold them on then then put one around each of these wires as close the the equipment box as is possible..
If by line isolator she means something with a wire coming out each end then cut the positive wire leading to the radio - as close to the radio as is feasible- and connect the isolator in series...ie the current goes from the battery to the isolator then out of the isolator and to the radio. similarly with other bits of equipment such as the positive supply to the modem and computer.
Keep all these leads as far from the antenna and antenna tuner as is possible. The coax lead from radio to tuner would benefit from fitting ferrite snap-on rings.
If that coax lead has extra length then coil it up into a continuous coil (ie not just a to and fro jumble) and hold its shape with sticky tape around an empty plastic bottle to act as a core. That in itself makes a choke to stop rf currents being carried on the outside back to the equipment. Make such a coil about half way between the tuner and the radio.
Try to run a separate positive and negative lead for each bit of equipment back the battery or battery switch [ instead of having one lead to a common point and then branching out. ] You do not want the voltage drop at the radio caused by its 25 amp current to be passed on to the other items.
drop-out due to low voltage can be ameliorated by turning back RF power of the transmission so it uses less current and thus loses less voltage.
Take the earth lead of the tuner directly to the nearest earth point by the shortest route. not via a wire leading to the radio earth. Check that the PL 259 plugs are well screwed in to make good earth contact. PL 259's are the coax plugs. A good earth for the tuner can be formed from a length of chain towed through the water over the stern. connect a stout wire from chain to antenna tuner by shortest route. If you try the chain then try disconnecting the "earth" you have for the tuner now. All these myriad lengths of copper foil stuck around the hull and tacked on to keel-bolts which 'a man in a bar told my ex-wife his cousin's friend used to use " can sometimes make things worse than a simple direct bit of chain going down in to the water.
If you choose to heave-to so the chain hangs down while you use the radio that make for less general recieve noise which can trip out automatic connecting programs for modems.
Bryan- 40 years in ham-radio
SSB
Tell her that some PTC units (including mine and 3 others that I am aware of) are temperature sensitive. While they work well in the tropics, they don't like cold mornings, and exhibit the same error messages and problems she is getting, especially at lower battery voltages.
The solution is to (1) warm them up--I use a cup of coffee on top of mine at anchorage, but she will have to get more creative at sea-- and (2) turn them on at least 10 minutes before you try to connect. - Don
SSB
The line isolator is one from Radio Works, it goes in the coax between the tuner and the transceiver. She will need a short length of coax with PL-259 connectors on each end. Install it near the transceiver.
The ferrites go on control cables, DC power cables and, if you have enough of them, on the coax as well. Probably don't need to worry about the coax with the line isolator in place.
The other problems she describes may or may not be due to RFI. Sounds like she has a low voltage problem....have her check all connections CAREFULLY....and be sure the power wires are large enough. The radio, if possible, should be connected directly to the house battery bank, with only 25A or 30A fuses on both the positive and negative leads.
Propagation has been lousy for quite some time; this may be longest "low" of any modern sunspot cycle, with very low sunspot activity. There are recent signs it may bottoming out...we all hope so....and things may be getting better before too long.
Hope this helps,
Bill
S/V Born Free
RF interference - SSB
Here's an excellent article by Jim Corenman on taming RF interference:
http://www.airmail2000.com/rfi.htm
As that article says, you'd want ferrites on all of the control cables running among the transmitter, its control panel, the Pactor modem, and the computer. The isolator goes near the antenna tuner at the tuner end of the transmitter-tuner cable.
Since sub-par voltage seems to be an issue already, I'd want to be sure that the power cables to the SSB are plenty beefy and the connections are all good (and equipped with ferrites). It would be a good idea to look at the input voltage at the transmitter during transmitting too. Since the PC (laptop I assume) has its own battery, so its power level shouldn't be affected. If the Pactor modem draws its power from the transmitter, and your power source is bad, that could cause erratic Pactor behavior and give the serial/USB converter and computer fits too.
A bad antenna ground/counterpoise could cause much more mischief. I'd be checking all connections and be sure the ground foil isn't corroded or otherwise damaged.
There are other folks on this board (Brian? Rick?) and elsewhere who have worked on scores of boat installations. I have not, but consider myself to be a better than average electrical troubleshooter.
So... the zero-th rule of troubleshooting? Never assume anything... It might not be an RF interference problem at all. Could be a power problem.
And the 1st rule of troubleshooting... What changed? Was it ever working correctly? If so, what changed in the interim?
I hope this helps!
Charlie
As just posted on THT,
As just posted on THT, generally redundant with mos previous...
It is just about impossible to accurately diagnose the problem without a great deal more information and testing. Also, I am uncertain what is meant by a "line isolator". Having said that, and assuming the system previously worked well, here are a few thoughts.
It sounds like there is either RF getting into the system, low voltage, or a failure internal to the hardware .
Low voltage:
12.4 volts should be sufficient, *IF* the measurement was made while the radio is transmitting. The transmitter will draw considerably more current when transmitting. If there is a higher than normal resistance in the power feed (poor connection) it could easily read 12.4 under receive but drop much more when transmitting. Check the voltage at the system when transmitting...
RF interference:
RF getting into the system could produce the symptoms. Sounds like the isolator and ferrite chokes are an attempt to mitigate this type of problem. Stray RF can arise from several sources. A bad ground, a failed antenna, or a broken antenna tuner would be the most likely sources. An SWR (standing wave ratio) measurement at the radio would shed some light on this. Poor SWR can result in RF getting where it shouldn't as well as causing the transmitter to reduce output power (Most radios self protect by reducing power output under high SWR conditions. It should be between 1:1 to 2:1. An SWR meter is needed to check this. Often radios have this function built in and can display either the SWR directly or "reflected" power. For a radio with 100 watts output, 10 watts reflected is about 2:1 SWR. A broken antenna, poor ground, or problems with with an antenna tuner/connections can cause high SWR.
Ferrite chokes help reduce RF getting into the system, but may not eliminate the problem, especially if the SWR is high - the transmitter will still throttle back the power. Where to put them will depend on where the RF is entering the system. On the coax at the antenna end of a coax line, on each end of the connections between the computer and the radio, and the power feeds to the computer and radio are the most likely locations. Check grounds, SWR.
Wish I could be more specific, but there are a huge number of variables/possible problems. Perhaps someone who has solved identical problems can chime in...
Woody, Ham Radio since 1961.
Rf Interference - SSB
Hello all
I have read the above suggestions and agree with all, the most productive ideas, in my expirience, will be grounding, and power feeds.
Ie. I would common ground all the equipement to each other and then to a ground source thru the hull, to the keel or outdrive, or even a water fitting, if that is not possible then ground to the negative side of the battery.
The suggestion to put chokes on all the data lines is also good.
The problem looks to me to be RF inside the living quarters, easy to check if you had a field strength meter, but the one thing I have not seen addressed yet is the antenna. I will assume your using something like a backstay for an antenna, something that is none resonant for the frequencies your transmitting on, if this is the case then you most likley have RF coming back on the outside of the feedline.
I would suggess you try coiling the coax, outside the cabin, in a coil about 8" diameter and about 6 - 8 turns, taping it so it will stay neat.
This coil will help stop the RF from getting back to the equipement. If don't have enough coax to make the coil, then place a couple of chokes over the feedline just before it enters the cabin.
Now for the modem, I would definitely do as suggested above and try to seperate the power feed of the modem from the radio. I believe the power fluxuation caused by the radio in transmit is causing the modem to spasm. Finding a clean steady voltage for the modem should eliminate the problem. The modem should be able to run on much lower voltages than 12.4v
Also seperate all coaxs away from the audio leads and power leads to the computer and modem.
I have had similar problems with equipement in my Ham Shack with RF creating havoc with computers, a paccom modem and transmitter audio as well. I was able to eliminate it with equipement grounding, and chokes on the feedline outside the station.
I hope we have helped you with our suggestions.
God Speed, and safe sailing
Kevin
SSB Problem
HI, I'm Dick W4NWD. I have sailed and used HF for e-mail aboard for 11 years. My boat s/v Triumph is in Turkey now, and I am in Florida.
I'll give you my quick fix suggestions for Jeanne, but it may take a few more correspondences to find the total problem.
1.The line isolator should be placed in the coax between the Tuner and the HF radio. The closer to the tuner the better. A short coax with two PL259 connectors is required to connect.
2. Be sure the ground on the tuner is good. The tuner should be grounded to the boat bonding system. Do not ground the radio to the boat bonding system. ( Most commercial installers connect it anyway)
3. Separate the computer and the Hf xcvr if possible. Mine worked fine with about 12 inches between them, but further the better.
4. The ferrites go on both ends of every cable connecting the radio, modem and PC. I just bought 6 Mix 31 ferrites for this purpose to use on our radio club station set up.
5. A few un substantiated things to try are to run lower power, I used about 20 watts
6. Place a sheet metal isolator under the PC ( lap top). License plate road sign etc.
7. Check all 12 volt power leads if the voltage is low each time the transmitter keys, the voltage to the modem will drop causing major problems with otherwise stable connections. Be sure the 12volt leads connect directly to the battery and twisting the leads will also help.
8. Check the connection between the tuner and the antenna. Remove clean and reinstall. I found the wing nut on top of my tuner had vibrated loose. Also eliminate any antenna switches in the feed line for a test.
9. Check the Airmail, tools, options, and see that 1500, USB and FSK= 425, PSK=425 are the settings. I have used FSK and low as 225 and as high as 650. but I like the 425 since it controls the amount of power you are running.
10 Try Bernie, PMBO WG3G in Trinidad, He is a great guy and usually put our a good pactor signal.
I hope this helps, Let me know If I can help further, I'll be watching Jeanne's web site.
Fairwinds,
Dick
SSB Problems
Sounds like she needs more than just a line isolater. That goes right at the antenna tuner on the coax going to the radio. She needs other clip on ferits on the lines going to the modem and the power cords to the radio. This is a common problem and you just have to make sure your ground counterpoise is working right and put ferrits all along the cables in the system. Radio Shack has the ferrits or you can get them at Radioworks by googling the name.
Jay
SSB Help
I am just now learning about my Icom M802, and in doing so, I'm reading Gary Jensen's "The Sailor's Quick-Sart Guide". Gary owns Dockside Radio in Florida, and really knowledable about SSB stuff. In this small book, he addresses the use of chokes. He suggests using chokes made by FairRite, which contain Type-31 materials, which is not available in Radio Shack's chokes. The chokes should be placed at each end of antenna tuner control cable (PPC-1147 or OPC-566 in the Icom case). Also, a Common Mode Choke can be used to block stray RF current for traveling down the outside of the coaxial cable shield. Beyond this, I know little, but a look at Gary's book will be of additional help.
Ned PS Dana CAMELOT 152
SSB modem problems
Thanks everybody for your GREAT comments
You guys are the best!
I forwarded the information to Jeanne. I'll let you know how it goes.
Thanks again,
Kim (seageek)
I'm in St. Helena, Jeanne
Hi, Kim!
Thanks a lot for the info - please thank all concerned for their useful input!
I'm in regular contact with Jim Corenman, whose article I've read many times!! He is always very helpful - he's come up with a plan for installing my line isolator (which should help overcome some of my RFI problems) which I'll try out tomorrow.
Toured island & Napoleon sites with other 'yachties' here - excellent day (see 'blog' on website) but will concentrate on boat jobs & Clearance tomorrow, hoping to be ready for leaving on Wednesday for month-long passage to Trinidad.
A few comments relating to your YachtPals correspondents' points:
Am now using PCMIA card with two fast USB ports - has resuscitated old lap top for radio use - USB ports had both gone down... All connections were looked at recently & were bright and shiny & aerial connection is new (after re-rig)- but all being checked over when do tomorrow's line isolator installation.
Distances involved are too long to reduce power output on Icom M710. Ferrites (several at each end!) have 3 turns around where possible. SSB is fed directly from battery bank. Impossible to route feed away from other wiring. Antenna feedline isn't coax & is as short as possible since ATU is directly beneath backstay. Grounding system was recently improved vastly - 2nd copper strip added to 2nd ground plate.
Beefing up power cables to SSB is something I'll look at, but I think they're reasonably 'chunky' already. Laptop is always powered up from 12V supply.
Not a new problem - one I've had for a long time but have been trying, when not too busy with other things (like sailing around the world!!!), to resolve over last year or two... it's a complex problem... and I've still several other ideas to try when I stop somewhere, eventually, for long enough.
"1st thing I'd do - put a voltmeter on the radio and watch what's happening when it tries to connect."
Where would the voltmeter go - across output to antenna, I presume?
Thanks again to all for their ideas - plenty to think about...
Cheers,
Jeanne
"Nereida"
St Helena, S. Atlantic
Volt meter
Would go across the 12 v feed point, nearest radio if possible. If it dips down below 12 when radio is in transmit mode, then connections are dirty and or wire size is to small. You can increase wire size by putting another one of the same gauge along side the orginal one, red to red, black to black, DO NOT SHORT THEM. Keep the postive together and the negatives together.
If the voltmeter goes up when you transmit, the rf engery is getting into voltmeter and it is acting like a receiver. Will have to get farther away from radio antenna.
Most important is to make sure your ATU has a good ground. Also you will have to check all your connections from time to time, due to the salt all around you. Once a connection is clean, you can all ways put grease on it to help keep salt away. Not a good ideal if it is where you touch it a lot.
Good grounds, clean connections, heavy wire so there is no voltage drop are key things to keep in mind. Also you can take the frequency and divide by 234 and put additonal wire from ground side of tuner or better yet antenna and make up your own ground plane, they can even go into the water if necessary.
Good luck, will follow with interest to see where problem was, never to old to learn some more.
Alex
kr6g
Quincy, CA
St. Helena
Full report, please! The place is fascinating, as isolated and infrequently visited as it is.. definitely not on most yachties' itinerary..
I'm fairly well convinced that this is mostly a power supply problem. You're using two plates through the hull and copper tape, so the ground would appear to be sound. In fact, if it was done right, it's the optimal setup! Make sure the antenna tuner is also grounded (and ditto everything Alex said). I am concerned that BOTH USB ports are fried. If they failed while connected to your SSB system, stray RF may indeed be a factor.
Check the voltage drop at different power settings at the DC power connection on the radio. You will get some drop, certainly at max power, which is why the cabin lights dim. Check your radio's specs and see what the min operating voltage is and compare. I may be wrong, but I should think that anything much below 12v is an issue.
You are not supposed to have coaxial cable running from your tuner to the antenna feed. It should be a single, well-insulated wire. Amateur equipment would have coax or "ladder line" at that point, but marine tuners aren't designed that way. Your antenna literally begins at the wingnut on the top of the tuner, which is why you want to keep the run from there to your backstay "feed point" as short as possible. Since this hopefully short run is a radiating element, any conductor running adjacent to it is a good candidate for bringing RF energy to places it shouldn't be. The RF connection from the back of your radio to the tuner is coax, of course. All this is a complete non-issue with a competent, professional installation, but I've seen some work, as have we all.........
It might be helpful to remember that your antenna on the boat is composed of two equally-important parts -- the antenna itself and the counterpoise. The radiating element itself is a poor one on a sailboat, usually, end-fed, random length, made of braided stainless steel wire and placed in close proximity to other structures that interfere with your ability to hear and to talk. The other part of the antenna is your counterpoise, your RF ground, and that saves the day for you if it's connected to your radio and tuner properly. Maximize the advantage that you get from a good RF ground. Make sure that you remove any green corrosion from all connection points of your copper tape conductor at both the equipment side and the through-hull connections to your plates. Apply conductive lubricant to all RF connections except coax. Nothing but copper tape -- no ordinary wire anywhere. Even if it turns out not to be the source of your current problems, a quick inspection is a good idea. Good luck!
Steve McWherter
St. Helena Cruising
You can read more about Jeanne and St. Helena here: http://yachtpals.com/boating/saint-helena
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