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Old 05-18-2012
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Re: SSB Antenna wire attachment to the backstay

I usually agree with both of you, but, this is one particular instance where I do not. The clamps, both types, are not great for making a good electrical connection to the backstay. Yes, both will work, at least most of the time, but I think I may have found a better solution to this age-old problem.

I stripped about 4-inches of insulation from the wire's center conductor, then lightly twisted the wire back to somewhere close to its original shape. Next, I lightly tinned the stripped section of wire with rosin-core solder. After it cooled, I placed a dab of silicone cement to the base of the wire, thereby providing a waterproof shield so there would be no water intrusion between the insulation and wire.

Attaching the wire to the backstay was simple. I merely wrapped the tinned section of wire around the backstay, then tightly wrapped the connection with white, rigging tape. A small, white, cable tie was placed at the top and bottom of the rigging tape to anchor it in place--just to be on the safe side. No big lump from the connection, nothing to get snagged on, and when I have to remove it, which in my case is necessary when the boat goes onto the travel lift, I just snip the cable ties and unwrap the tape--it takes just a few seconds.

I've measured the connection resistance with an ohm meter many times to ensure that it is solid--never had a bad measurement. Additionally, there's no pressure point or chafing of the backstay whatsoever.

I think the biggest problem I see with SSB radio installations is the grounding system. Essentially, this is a longwire antenna, which requires an earth ground to operate at peak efficiency. Most installers have the tendency to attach the ground post of the radio to the negative terminal of the boat's batteries and assume this constitutes grounding--it does not. Even if the engine is an inboard that is grounded to the negative terminal of the battery, the ultimate connection to an earth ground, which in this case is the water, it not always adequate. Sometimes it works, sometimes it just doesn't. The best connection in this instance is an external ground plate, one that is often used for grounding the mast for lightning strike protection. It's a solid, ground connection that makes a huge difference in the reception and transmission of SSB radio signals.

I'll shoot some step by step photos and post them when the boat goes back in the water.

Cheers,

Gary
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