Been There Done That
You might want to figure the weight of what you have to lift. One would
think it was, like, duh, you make a wire vertical and fill a balloon
full of helium and ... but it turns out you need to be careful about the
weight of the wire and insulators and you need to project how much
helium you can use and how much lift you will need and ... all that.
Just saying all that because the last thing you want to find out is,
after you've got it all together, you just can't get it up in the air.
I seem to recall I needed more like a 3 or 4 foot balloon to lift mine.
And be careful of the sticker shock on the gas. I thought it was a lot
of money 20 years ago. Rumor has it, it has not gone down in price.
The first one worked well until I had a bad wind.
The second one had some kind of corona arc off the top of the wire which
popped the (relatively expensive) balloon after only a couple minutes of
testing it out. Or something. It popped on a clear calm day but under
Full Power.
Anyway, that wrecked my day. I decided it wasn't fun any more and have
been using more conventional 160 meter verticals since.
I think we wrote it up in the NCJ but don't remember and have slept
since then.
Oh sorry, you asked where to get the balloons. I think I got mine from
a party supply store. It was not mylar.
Note - Googling reminds me of these facts:
Helium can lift 1 gram per litre.
A balloon 2 feet in diameter will contain 118 litres of helium.
That will lift 118 grams of antenna, = 4.1 ounces.
132 feet of bare #18 solid copper wire weighs 10.4 ounces.
A 2 foot balloon filled with helium will not lift a 160 vertical made of
#18 wire, not to mention any extra line or insulators, etc.
But a 4 foot balloon will lift a little over 2 pounds.
Now I'm having nightmares again.
73 - Mark N5OT
On 11/8/2021 2:48 PM, Dick Bingham wrote:
Greetings All
I want to try a balloon supported Vertical for 160.
Any advice on sources for balloons? Mylar material
and diameters up to 2-feet would be my choice.
73. Dick/w7wkr at CN97uj
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