Insulating BackStays for SSb antena cable

[Carlisle Spirit]

Surely there is a way for me to insulate the cable / backstay so that i dont have to have those ridiculous step-out insulators ( which hold the cable away from the backstay )

Any advice on this one ?

[Carlisle Spirit]

oh - i failed to submit the need i have

I want to use the already insulated backstay as an SSB antena

[Cheechako]

You can try it without them, see how your signal does. Some people have mentioned they dont think they are necessary. Your bottom insulator must be high up? Nice to have something to keep the cable from moving around anyway though... will a few standoffs really be that detrimental? Have someone carve ornamental ones out of teak!

[Carlisle Spirit]

Just wondering if there is some material I can use to avoid the "stand-out" thing

It's not about aesthetics

It's more about flying sheets destroying the cable separation.


CS

[Cheechako]

You would need a shielded cable with the shield grounded one end only I think... and the problem is that the shielding tends to drain the power of your signal. Is this on a side stay ,....not the back stay?

[CAELESTIS]

I didn't use stand offs. I ran the GTO 15 inside a fuel line hose and wire tied directly to the backstay with no problems.

I did see a boat with a routed starboard panel that was used instead of standoffs, and that is what I would consider if I needed the separation.

[Carlisle Spirit]

Thanks for the thoughts

[svinshallah]

When you series feed a vertical long-wire antenna (i.e., at the bottom) the entire wire from the antenna tuner terminal to the upper insulator becomes the antenna. If the backstay below the lower insulator is grounded, there can be enough capacitance between the feedline and the backstay to affect the ability of the antenna tuner to tune at some frequencies. Separating the feedline from the backstay wire will reduce the capacitance.

The lower end of a series-fed vertical is also a high voltage point, so separating the feedline from a potentially grounded lower backstay could reduce the potential for arcing.

Note that on a metal hull, the bottom end of the backstay will definitely be grounded, hence the lower insulator. On a fiberglass boat, unless the chain plate is actually bonded to ground, you are only worried about leakage caused by moisture and salt.

[roverhi]

If your stay is insulated, all you need to do is tape the feed wire between your tuner and the insulated part of the stay to the backstay. On two boats, have done this and have had no problems getting out. Stand offs aren't needed. Don't need coax to run from the tuner to the insulated/antenna part of the backstay. Use GTO 15 insulated cable.

If I had to do it again, would only put an insulator near the mast head. No bottom insulator needed on an FRP boat. Run the feed wire from the tuner to the backstay at the turnbuckle. As long as the backstay is not bonded via the chainplate to the boat, the antenna will work fine. Just warn everyone not to hang on to the backstay while you are transmitting. Even then, doubt that anyone hanging onto the backstay would suffer much ill effect from RF energy. I'll stand by while the tin foil hat crowd has fun with this.

[Carlisle Spirit]

Originally Posted by roverhi

If your stay is insulated, all you need to do is tape the feed wire between your tuner and the insulated part of the stay to the backstay. On two boats, have done this and have had no problems getting out. Stand offs aren't needed. Don't need coax to run from the tuner to the insulated/antenna part of the backstay. Use GTO 15 insulated cable.

If I had to do it again, would only put an insulator near the mast head. No bottom insulator needed on an FRP boat. Run the feed wire from the tuner to the backstay at the turnbuckle. As long as the backstay is not bonded via the chainplate to the boat, the antenna will work fine. Just warn everyone not to hang on to the backstay while you are transmitting. Even then, doubt that anyone hanging onto the backstay would suffer much ill effect from RF energy. I'll stand by while the tin foil hat crowd has fun with this.

I think this is an excellent suggestion

Even though I already have insulators top and bottom on the back stay , the principal reason I think this is an elegant solution is that I can avoid drilling any holes in my deck

Will jump wire to skirt around the bottom back stay and insulate any part if the back stay within reach of crew to prevent injury

CS

[Goudurix]

Sorry CS,

there is "Good Practise" for everything.

The first thing I look at when seeing a sailing boat docking or when visiting a marina is watch if they have any signs of "SSB-on-board".

Countless boats do have insulated backstays; sometimes the lower insulator quite high up, and then run a wire yes or no extra insulated in a hose, strapped along the lower end of the backstay.

As mentioned above, the lower part of this type of end fed wire antenna is high voltage.
You do not want to run it that close another conductor labeit insulated or not.

Look at it this way N°1: neat nylon or other plastic standoffs will give it a real "professional" look

Look at it this way N°2: is it a problem to sail your boat with badly trimmed sails? It will still move.....is it a problem to hose down your boat or fill your water tanks with the water hose jammed or teh water flow severely restricted? No you will be able to hose it but rather slowly...

Look at it this way N°3: will you install your marine VHF antenna on deck level if you can install it in the masttop providing you have a good quality low(er)-loss coax? Nope....Will you be able to transmit on marine VHF with your antenna on deck level? yes for sure....how far?

Well good practise (which is of course backed by science & physics) mandates using stand-offs and also leading the bottom wire to the antenna tuner in the best practise way....that bottom wire is also part of your antenna. It is the choice between the best option and a less-than-optimal installation....

Jan

[Goudurix]

And the "good practice" for "Good Practice" is to write it with a "C"

Oops!.....

Jan

[Wotname]

Originally Posted by Goudurix

And the "good practice" for "Good Practice" is to write it with a "C"

Oops!.....

Jan

Even better, write it with a "c" and not with a "C"

[Goudurix]

A "C" is a "C" is a "c"...

[Carlisle Spirit]

Thanks for those thoughts

Good practice to me means continually evolving a solution, so that it becomes even better


If I can use the back stay itself as the aerial ( properly insulated to prevent injury) and at the same time avoid drilling a hole in my deck , that sounds like a better solution to me

It means I connect the tuner to the chain plate below deck , without running any other wiring either through the deck or above deck

Total signal output should be about the same according to the guy helping me install the ICOM tuner