Make that corona flashover an EVENT at your next QSO party.
73 - Mark N5OT
On 11/8/2021 5:41 PM, Gary K9GS wrote:
Use Hydrogen!73,Gary K9GS
-------- Original message --------From: W7TMT - Patrick <W7TMT@outlook.com> Date: 11/8/21 4:54 PM (GMT-05:00) To: Mark - N5OT <r-emails@n5ot.com>, TopBand List
<topband@contesting.com> Subject: Re: Topband: Balloon Supported Vertical Regarding the helium…Be advised the gas used by the party stores these days is almost always a mixture and not pure
helium. That’s means considerably less lift. You’ll likely need to source the good stuff from a industrial gas supplier.W7TMT________________________________From: Topband
<topband-bounces+w7tmt=outlook.com@contesting.com> on behalf of Mark - N5OT <r-emails@n5ot.com>Sent: Monday, November 8, 2021 1:17:53 PMTo: TopBand List <topband@contesting.com>Subject:
Re: Topband: Balloon Supported VerticalBeen There Done ThatYou might want to figure the weight of what you have to lift. One wouldthink it was, like, duh, you make a wire vertical and fill a
balloonfull of helium and ... but it turns out you need to be careful about theweight of the wire and insulators and you need to project how muchhelium 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 lotof 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 whichpopped the (relatively expensive) balloon after only a couple minutes oftesting it out. Or something. It
popped on a clear calm day but underFull Power.Anyway, that wrecked my day. I decided it wasn't fun any more and havebeen using more conventional 160 meter verticals since.I think we wrote it up in
the NCJ but don't remember and have sleptsince then.Oh sorry, you asked where to get the balloons. I think I got mine froma 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 N5OTOn 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> _________________> Searchable Archives: http://www.contesting.com/_topband - Topband
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