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INSTALLATIONS AND SSB ANTENNAS For Satellite/WiFi Antenna Mounting Tips Click Here! "AT LEAST 80% OF THE ABILITY FOR ANY RADIO TO COMMUNICATE
EFFECTIVELY
Discussion on Grounding I have been asked many times what's is the big deal about SSB grounding (Groundplane or counterpoise) and why so many damn theories on it anyway... I truly think it's a great way for someone to attempt to prove how much they know (More likely don't know) and, when asked specifics, tend to fold up, conger up, or pass along some bad information they heard during some other B.S. session and maybe write a book about it. If it's a salesman...that's a no brainier what they are up to... Buy this toy or that and it will save you from all that work to do it right.... Right? Wrong! Grounding (Groundplane or counterpoise) is not black magic nor difficult to understand once you see the big picture. Goto Grounding Ideas Page for details on lightning suppression/control. As you may have noticed in the above chart for SSB antennas, there is a marriage of larger overall antenna length combined with a larger amount of groundplane or metal surface they are working with, equals better performance (Higher efficiency). That's it! You are now a antenna master... go out and prosper! Well it might not be quite that easy but close due to that simple rule of the larger the radiating surface the higher the efficiency overall. How you achieve this is another matter but should not vary much at all from the basic rule that made you a master in the first place! Several things to think about when installing on a vessel:
Remember we are looking for surface area... not length so it's a matter of how to generate surface. This is where you hear about tying holding tanks, rudder posts, keel, toe rails and ANYTHING metal together with the results of a LARGE surface and not just one or two items hooked up at the tuners ground lug. New boat makers still have not figured out that SSB is back with inexpensive e-mail and data services and still don't often "glass-in" copper mesh into the hulls unless you specify it. That would be much to easy! If faced little to no metal workable on your boat (No metal anything), take a trip to the hardware/marine store and get some copper or bronze window screening mesh, rosin core solder and soldering iron, copper or bronze nuts and bolts, a tube of silicone grease... clean out that bilge and cubby holes like you said you would do last year and start figuring out how to get as much screening down there flush to the hull and up along the walls as possible. If you can get two 6 by 2 foot pieces of mesh between stringers tied together with a copper strap to the tuner... that's real progress! One thing that is very important is what and how you tie everything together with... Two inch copper STRAP NOT FOIL minimum. Why not foil? Picture what seawater does to thin metal and foil is really thin! Several customers went off and put foil down anyway and the result is they sounded great for about a year but after that... Radio interference (RFI) crept in more and more as the foil turned to dust. One customer didn't change it until he had no usable signal at all. Poor data thru-put cost you money in data signal corruption and retry times... Not pretty. The name of the game for the station owner/operators is speed and squalling radio data signals is a time killer. When you find a good size of metal, how should you tie it into the groundplane system? ONE WAY ONLY... Each metal item and the strap you tied to it, must be sent as directly as possible to the tuner ground lug or a common tie point within a foot or two of the tuners ground lug. Exceptions to this rule....NONE. (See Pic's Below). Overall surface generated is greater by this method as opposed to daisy-chaining them together. We won't get into RF (Radio frequency) currents that float around... (See Interference aboard boats) but by using this "homerun" method tends to reduce RF currents floating on wiring that it isn't suppose to. One last note to antenna masters out there is combinations of different technologies will help. Example, If you have put together as much metallic objects as possible then something like a Dynaplate couldn't hurt and add it to the mix. It's just the non-masters that swear that they are the ONLY thing you need to use will mess you up. A rather prominent book writing ham operator that will remain nameless... specifically says that due to the advanced tuner design, all you need is to ground the tuner to a few thru-hulls only!!! That is totally wrong and anyone that tells you this needs to stay out of the communications business!! You can tune a wet noodle but not a great antenna.... Remember the basic rules and you will be fine... So for the rest, you can find in this article Installation basics and look below for some ruff layouts. All the best and have fun with what you know!
Articles on proper installations aboard boats of any size as the basics are always the basics! Interference aboard boats PDF file
Basic Diagrams HF/SSB High Performance Antennas
Do not run a common ground strap down the center of the vessel and then tie metallic items into it. Follow these layouts related to all individual straps common at the tuner's ground lug to present a much larger RF surface area. If bringing all straps directly to the ground lug of the tuner is not possible, use one common 4" copper strap or flashing down to a point where you can tie them all in.. Not more than 3 or 4 feet away!
Diagrams of several Shore Station antennas types for Marine SSB use. Vertical ground mounted antenna
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