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SSB Ground
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On my boat, I have the Amel provided SSB installation with the whip antenna and 2 dynaplates on the skeg as ground. I've participated in the MedNet a bit over the last couple of years and have noticed that I often can hear boats yet they cannot hear me or can hear only a weak signal. More often then not, my transmission seems to come in weak. I have spoken to a number of SSB experts in the last couple of years and made some modifications to the installation which have been somewhat successful. I still think that I my SSB creates a weaker signal than most others. I've now spoken to another expert here on the US West Coast who suggests to increase the amount of ground the boat has by connecting more metal inside the boat to the ground system. I'm thinking of connecting the fuel tank to the SSB ground, for example. The connection would be by 7 cm wide copper tape - so it's not an easy thing to do as the fuel tank and the Antenna tuner are separated by a watertight bulkhead. Has anyone done this or done something else that has helped?
Many thanks for any advice! Cheers Joerg Joerg Esdorn A55 #53, Kincsem |
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Joerg, I am no SSB expert. Sometimes I think there is as much art to "fine-tuning" an SSB system as there is science. Maybe you need advice from one of those "artists." You want to be careful in connecting anything that is connected to the bonding system and I believe your fuel tank is bonded. If so, connecting to it will connect you to everything that is bonded. Several SSB experts that I know suggest using resin to attach copper foil to the inside of the hull below the waterline to increase the ground area. Check the area I shaded which is inside your watertight steering compartment. I believe this is the actual hull rather than a false bottom. This area should be close enough to your Tuner to connect. Maybe covering this area with copper foil will give you a better ground. 
On Thu, Jan 30, 2020 at 8:59 AM Joerg Esdorn via Groups.Io <jhe1313=yahoo.com@groups.io> wrote: On my boat, I have the Amel provided SSB installation with the whip antenna and 2 dynaplates on the skeg as ground. I've participated in the MedNet a bit over the last couple of years and have noticed that I often can hear boats yet they cannot hear me or can hear only a weak signal. More often then not, my transmission seems to come in weak. I have spoken to a number of SSB experts in the last couple of years and made some modifications to the installation which have been somewhat successful. I still think that I my SSB creates a weaker signal than most others. I've now spoken to another expert here on the US West Coast who suggests to increase the amount of ground the boat has by connecting more metal inside the boat to the ground system. I'm thinking of connecting the fuel tank to the SSB ground, for example. The connection would be by 7 cm wide copper tape - so it's not an easy thing to do as the fuel tank and the Antenna tuner are separated by a watertight bulkhead. Has anyone done this or done something else that has helped? |
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Herbert Lackner
Hi Joerg,
in my opinion there should be no need of adding additional ground, make sure that the connections are clean, no corrosion on any contacts, from tranceiver to tuner to antenna!, and also check the ground connections for contact / corrosion. Also check the dynaplate if it is clean and not painted... Transmitting problems are very often connection problems on the path to the antenna (antenna - tuner connection...) If you decide to add anything else to your ground system that is connected to the bonding system (and this is the only thing that will make your ground better, or - of course - copper foil) then make sure that you put capacitors between tuner and bonding so that there is no DC connection between your tuners ground and the bonding so that only HF can pass. Kali Mera has no dynaplate, I use the bonding as HF ground, but separate it with capacitors so that omly HF can pass it, that works fine and does not change the Amel bonding philosophy. Bills idea is also good, but it might be a too small area for effective grounding. herbert, SN120 |
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Herbert Lackner
to be more specific: Your ground is the sea. So you need a good electrical (HF - high frequency connection) to sea-water. This is done by your dynaplate. If you connect your bonding system you will make your HF connection to the sea better, but you will probably connect Battery (-) via the tuner to the bonding system, this is what you do not want. But you can do that, if you make sure that there is only a HF connection from tuner to the bonding system, this can be done by making the connection using capacitors. They will block any DC connection but will allow HF. This is the typical installation on steel hull boats.
If you glue copper foil to your bottom you are building big capacitors (foil - grp - water) that also allow HF running through it. Just adding metal (like your tank) without connection to the water does not really help... herbert, SN120 |
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On my boat 90% of Electric and electronic Problems are Connection Problems. This also applies to the SSB radio installation. I would check all the connections from start to end for corrosion and weak contacts.
And remember: the antenna starts with the wire from the tuner to the whip antenna (or isolated stag): no contact or approximity to other wires. If not done already, check the SWR (stand wave ratio) of Your installation with an appropriate device. It gives you a hint of how much of the radios Energy that should go out is reflected. If Nothing helps, open the tuner and check whether everything is ok or there are signs of Burning. |
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I was suggested by an expert to line the entire floor of the stern locker with copper foil and then solder it to the ground of the antenna
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Fair Winds HEINZ Quetzal, Sm 2000, 292 Am 30.01.2020 um 20:06 schrieb Daniel Frey <Daniel.m.frey@...>:
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Heinz, I believe most of that area in an SM is a false floor that is glassed in above the actual hull. Bill --
On Thu, Jan 30, 2020 at 2:00 PM heinz@... <heinz@...> wrote:
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Olivier Beaute
Hello Joerg, all the metal parts of your AMEL 55 (including your fuel tank) are connected together with the green/yellow wiring net and with the zinc anodes of your rudder EXCEPT the SSB ground-plates, tuner and transceiver. DON'T CONNECT the SSB ground plates to anything else, especially the general zinc ground circuit !!! You would then send a lot of power to all these metal parts while transmitting (moreover if you speak loud!). The HF-SSB radio system must absolutely be isolated from anything else, including yourself (don't touch the antenna while trasmitting). Moreover, connecting to something which is not in contact with water (your fuel tank) would not dispatch more power (the purpose of the ground plates is to dispatch the excess of power while transmitting). You'd better: - check all your connections on the SSB system -clean the ground plates thoroughly (with some acid stuff in order to remove the scaling) -check the continuity (0 Ohm) between the ground plates and the copper strap in the lazarette and the transceiver ground terminal -check the good contact on your whip antenna Good luck and be prudent with electrics. Olivier. |
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Dave Ritten
Hi Joerg I believe that it is hard to improve on a direct connection system using dynaplates. If the connections are good and the dynaplates are relatively clean then I am not sure that extending the ground by adding capacitively coupled (internal foil) or bulk (tanks/engine) will increase performance. A while back I came across an article (which now I can't find!) which was doing a relative test of a KISS counterfoil and other options, they found that a simple connection to a bronze through hole gave very good performance. I would first be focussing on power to the radio, cabling connections and condition, antenna etc. No doubt you have been through those tests but I attach a useful article that gives some guidelines about trouble shooting marine systems. Having a good SWR meter and a dummy load are invaluable tools in working through a process of elimination. In my experience bad connections due to crimp only PL251 connectors and corroded terminals/cable often is a problem on TX. All PL251 connectors must be soldered. Replacing the ATU/antenna connection and checking that it's routing is clear is also another gotcha. Antennae also fail - try the antenna test in the article. When trying to fine tune a system the biggest issue is measurement - how do you actually know that your system is underperforming when there are so many variables like propagation conditions etc. You have to rely on distant boats to call out what your transmission is like and that is very subjective based on their opinion, location and their receiver etc. I discovered a neat trick recently - there is a global network of enthusiasts who run software defined radios (SDR) that you can connect to over the internet. These SDR's were developed in NZ and known as the kiwisdr. Basically you fire up a browser on your laptop, connect to one of the kiwisdr hosts like https://ve3sun.com/KiwiSDR/ and then you can select an active receiver close to you and tune it to whatever HF frequency you want. You can then listen on your laptop to what that receiver is picking up. You then setup to transmit on that frequency and away you go - you can listen to yourself, as received by that site. This allows you to make incremental changes to your system and see if they make any difference. You can change frequencies and start running really definitive tests. You can change receivers to see how far you can transmit! For example you could attach a temporary strap to your fuel tank and see if that makes a difference, or get a sheet of copper and hang it over the side of the boat. I hope that this helps, at least I am sure that you will find it interesting to play with the kiwisdr network as it is fascinating to listen to what you can pick up on radio receivers scattered around the world.
Best Rgds -- Dave Ritten Auckland Prospective SM Owner |
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Herbert Lackner
HF shall do no harm neither to the Amel bonding system nor to all connected metals, even if transmitting with high power. It is the DC connection that has to be avoided, and this DC connection will be created by attaching tuner ground to the bonding system. To avoid that this connection has to be "DC separated" by capacitors (HF coupling capacitors, bunch of them soldered together), then the bonding system can be used as a nice HF ground without negative impact. Only if there is no dynaplate!
herbert, SN120 |
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Thanks very much everyone for responding. I had thought I would disconnect the tank from the common ships ground and connect it to the SSB ground. I have been checking my connections since the boat was new in 2016 and replaced the cable from the transmitter to the tuner, replaced the antenna cable from the tuner to the whip - connection to the whip was not good, replaced the cable connecting the Dynaplates to the tuner with copper tape. All these things have made a difference between nobody hearing me to people now hearing me ok some of the time. But as I said in the original post, I still often have the situation where I can hear another boat quite well yet they cannot hear me. This indicates to me that my transmission isn’t as good as that of the other boat. I have been told that the whip antenna is not as good as the insulated backstay on most boats in low frequencies - the MedNet mostly operates on the 6 MHz band. So that may be one reason. Dave, many thanks for sending the troubleshooting articles. What instruments do I need to test the system?
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Herbert Lackner
Joerg,
* what cable did you use for connecting the antenna with the tuner? should be a GTO-15 and no coax / copper cable. This is sometimes the problem. * make sure that this cable is away from other metallic objects and that it is as short as possible, it is already part of the antenna - and the area where most of the power is transmitted * connection from this cable to the antenna (and tuner) is critical! minimum resistance necessary! checking/measuring/testing the system (standing wave ratio etc.) needs some specific technical HAM radio knowledge. herbert, SN120 |
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I would test the SWR (stand wave ratio) of your system. It tells you how much energy which is going out is reflected. With a device like this: (there are others which can do the same)
https://www.radioworld.co.uk/daiwa_cn-101l_meter_1_8-150mhz And by the way: do you speak loud and clear when you transmit, and close to the microphone... ? 😉 Did you mention what type/brand of SSB you have? |
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Wolfgang Weber <webercardio@...>
Testing with SWR- Meter from exampel Diawa is an easy test or look for help by a local HAM-radio Club. Try to google your Location and Ham-radio Club. Wolfgang Do8ww SY Elise Amel 54#162 |
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Herbert,
Here is some good basic info regarding using an SWR meter... https://youtu.be/qSea5FjcTDE Cheers Alan Elyse SM437 |
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Herbert Lackner
Alan, good video! thx.
SSB installation and troubleshooting is sometimes tricky. I made my engineer's degree in electronics and telecommunication and are an active HAM radio user since many years, but - even beeing a kind of professional in this area - it took me some time to get my installation working fine. There are quite a few factors that might influence transmitting, also outside the active HF elements (e.g. compressor of the fridge...:-) ). most important - imho - , if the ground is ok, are "connections", good soldering at the connectors and the right cables, and understanding that the antenna starts at the tuner :-) fair winds, herbert, SN120, OE3HLA |
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Thanks again everyone for your advice. To respond to a few questions, I have the ICOM M802 with the AT140 tuner. For the cable between the transmitter and the AT, Amel/Pochon installed RG213 and I replaced it with Aircell 7. Antenna cable was something indeterminate but I replaced with GTO 15. I'm turning off the solar, refrigerators and some other things that interfer like the inverters. Would it be sensible for me to use the services of someone who knows how to interpret the results of an SWR meter after I've checked all the other things mentioned above? Cheers Joerg
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Herbert Lackner
Hi Joerg, you have the best equipment available installed. all parts are first class.
Of course you can check it with an SWR meter, but I am not sure if that will help you identifying the problem. Your antenna tuner (if it works fine) will make sure, that you the SWR is good, even if your antenna is not transmitting. In our typical boat installations the tranceiver will see a nice tuned antenna, even if it is just a piece of wire, because the antenna tuner simulates a nice tuned antenna to the tranceiver and the power might be used to heat up the tuner and not to escape through your antenna into the air - excellent SWR but nothing transmitted. But the SWR meter would help you in finding out if your tuner is working fine. Can you hear your tuner working? It should "click-click-cklick..." when you change to a new frequency and transmit a low power signal for tuning. the relais inside make some noise when they try to "tune" the antenna to a new frequency that the tuner has not stored in his memory. I assume the setup of the tuner and the tranceiver has been checked. You shall also set the AT140 in the IC-M802 initial setup as your tuner, you can also activate automatic tuning. to summarize: * check if your tuner settings are ok (I am sure they are) and that the tuner is tuning. If you have a SWR meter check that . * make sure your existing ground is working by cleaning your dynaplate and make sure connections are good, no other grounding is necessary (see Oliviers post), do not connect your tank * check if the GTO15 wire from the tuner to the antenna is free from any other stuff and that it is as short as possible * check your antenna contact and make sure the antenna is away from other stuff that hinders transmitting (eg. I use an isolated backstay on starboard, but have to make sure that the the mizzen boom is on port when I transmit...) * if nothing helps from the things above you should ask a local expert to check your installation (using a SWR meter, but also trying to find out what energy is really transmitted at your antenna, there are several options to do that) what I would not recommend without help from an expert: * changing your grounding * opening the tranceiver and trying to fix something there I am sure your problem can be solved relativ onsite easy by someone who is familiar with SSB installations on boats and who has the instruments to check it best wishes, herbert SN120 |
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Herbert, Very good advice. Bill
On Sat, Feb 1, 2020 at 11:03 AM Herbert Lackner <herbert@...> wrote: Hi Joerg, you have the best equipment available installed. all parts are first class. |
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Is your Icom 802 connected to the grounding (the dynaplates), too? If yes, disconnect it, as it may create electronic loops. The experts say, only the tuner should be connected to the grounding,
On my boat (Santorin) AMEL preinstalled a grounding wire for the radio at the navigation table to the tuner in the lazarett for the grounding of the transceiver (the radio). At the beginning I was using this wire to ground my Icom 801. But the experts recommend to not to ground the transceiver. So, I disconnected it. Now, only the tuner in the lazarett is connected to the dynaplates. More infos: https://www.svb24.com/en/guide/ssb-marine-radio.html http://www.sailcom.co.uk/m802/ |
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