Backstay insulator

[MM5AHO]

The eBay insulators don't have enough tensile strength. But if as you say you have twin backstays and can afford one to go completely slack (broken), then this would work, but don't tighten that stay.
The Stay-lok type fail safe, so mast doesn't fall down.
Ceramic Egg insulators don't have quite the compressive strength that they might appear to have. I remember crushing one (on land) guying a tower and was surprised at how little tension in the guy caused that to happen. But it is possible to get some strong enough for the job, but then they're no 99p, they're more like Stay-lok prices.
I have used a hoisted copper, (insulated) wire as antenna hoisted on a halyard. But thats a bit inconvenient, despite its far better conductivity.

Whip antennae are surprisingly good over the sea.

 

[Beadle]

Why not buy or even make a decent sized kite. Instead of string fly it with as long a length of thin copper wire as may be convenient and use that for an aerial. Any half decent ATU will tune it and it will get a better signal out than using a backstay.

 

[CreakyDecks]

At the end of the day it depends what you want the radio for. If it's just for chatting in a marina then any old DIY solution would do. If it was to be your last hope of calling for rescue in the middle of the Atlantic Ocean then you might look at it differently. I imagine the whole point of the seemingly over engineered Sta-lock insulators (30kV isolation) is to give some hope of them still working when things get really bad.

 

[Beadle]

At the end of the day it depends what you want the radio for. If it's just for chatting in a marina then any old DIY solution would do. If it was to be your last hope of calling for rescue in the middle of the Atlantic Ocean then you might look at it differently. I imagine the whole point of the seemingly over engineered Sta-lock insulators (30kV isolation) is to give some hope of them still working when things get really bad.

Thats fine

Except that if the reason you were down to your last hope was because you'd lost the rig your Sta-lock 30kv insulators would be of very litle help, but I could still fly my kite.

 

[KellysEye]

> If it's just for chatting in a marina then any old DIY solution would do.

The masts all around block tranmission, reception is OK to difficult.

>the seemingly over engineered Sta-lock insulators (30kV isolation) is to give some hope of them still working when things get really bad.

Thet are not over engineered they are designed to do the job of holding the rig up, thus different sizes for different sized rigging wire.

 

[MM5AHO]

> If it's just for chatting in a marina then any old DIY solution would do.

The masts all around block tranmission, reception is OK to difficult.

>the seemingly over engineered Sta-lock insulators (30kV isolation) is to give some hope of them still working when things get really bad.

Thet are not over engineered they are designed to do the job of holding the rig up, thus different sizes for different sized rigging wire.

Its not my experience that the masts in a marina block transmission.
I've had very good communications on HF from marinas with masts in them, but its true that they can reduce signals out.
In some circumstances other masts could actually enhance signals by causing them to be directed more one way than another. If other masts block transmission, they will equally block reception.

I agree that Stay-lok are not over engineered. Rather they ARE enginneered.