Decided to try this for 160 this season, but have a few questions for anyone
who might have tried one.
Picked up some neat "hollow" wire with kevlar liner at Dayton--very light,
but #14 size. Have the base, radials, etc. pretty well figured out, but
wonder about the balloon? Local gas supplier wants $35 lease for tank, $35
for regulator (purchase), and $32 for 121 cu. ft. of helium. (reasonable?)
Assuming I can find a 3' balloon, how long will one hold the gas?, how much
gas is required (simple volume of sphere is not enough--need to know the
typical pressure), any good ideas on locating a good balloon. Many thanks
for any suggestions.
John, K0IJL, CAC Dakota Division
>From w7ni@teleport.com (Stan Griffiths) Tue Aug 13 19:11:26 1996
From: w7ni@teleport.com (Stan Griffiths) (Stan Griffiths)
Subject: RF Exposure
Message-ID: <199608131811.LAA00207@desiree.teleport.com>
Something seems a little screwy with all of this RE exposure stuff I am
reading lately. The object of the new regs HAS to be a well-meaning attempt
to keep people from being damaged by exposure to RF. (or it is just a front
for a new way to get rid of my towers?) We all know that RF field intensity
goes up rapidly as you get closer and closer to the source. So how come
there does not seem to be IMMENSE CONCERN over radios that you actually wear
on your body?? (cell phones and handhelds) You can't get much closer than
that and the field intensities have to be very large even at just a few
watts of power.
There must be tens of thousands of ground-mounted HF verticals that you can
walk right up to and touch. What sort of intensity does one of those put
out with 49 watts into it at a distance of 1/2 inch?? Whatever it is, it
must be OK since it is exempt. So when we find out what that intensity is,
I would think all we have to do is prove the intensity we put out from our
tower mounted beams is less than that so it, too, must be OK, since it is
less than a system deemed so harmless it is totally exempt from the rules.
This argument may only get us into deeper trouble, but I would suggest that
it might cause a re-examination of the risks associated with handhelds
(including cell phones). If we hams are going to risk getting into trouble
over this, I damn sure want to drag the cell phone companies right into the
muck with us. At least they have the funding to defend themselves and if
they lose (impossible!), the loss of cell phone conveniences will be
devastating to the general public (which is why they CAN'T lose).
Stan w7ni@teleport.com
>From gswanson@arrl.org (Swanson, Glenn, KB1GW) Tue Aug 13 23:07:00 1996
From: gswanson@arrl.org (Swanson, Glenn, KB1GW) (Swanson, Glenn, KB1GW)
Subject: Call Corr
Message-ID: <m0uqQhH-000fCsC@mgate.arrl.org>
That should be K5IS..
"From a 14-page article by NK5IS and N5UDJ:"
>From gswanson@arrl.org (Swanson, Glenn, KB1GW) Tue Aug 13 23:06:00 1996
From: gswanson@arrl.org (Swanson, Glenn, KB1GW) (Swanson, Glenn, KB1GW)
Subject: balloon verticals
Message-ID: <m0uqQhG-000fCnC@mgate.arrl.org>
From a 14-page article by NK5IS and N5UDJ:
"Balloons: Buying surplus balloons may be a false economy. The Kaysam
balloon has an initial thickness of 0.0035 inch; at burst altitude, it will
be approximately 0.0001 inch. This is extremely fragile. If the age of the
balloon is past the date code, the surface material may have lost
"elasticity," and it can burst whenever or wherever it chooses. It is much
better to work with "fresh" balloons. Be careful to avoid directly touching
the balloon with bare skin, because the body oil from the skin attacks the
balloon material. Soft cotton gloves or surgical gloves are a good choice to
wear while working with the balloon.
Balloons come in a variety of sizes, starting with as little as 30
grams up to huge ones that require 12 bottles of helium to fill. Table 1
lists approximate price and burst altitude. Of the various balloon
suppliers, Kaymont Comnsolidated does not have a minimum order. See the list
of sources for the address.
Table 1:
Toltex size: Price: Burst altitude: Payload weight:
(grams) (US) (feet) (lbs.)
100 $7.50 40,000 1.5
300 $15 76,000 4
800 $28 99,000 6
1200 $45 104,000 over 6 lbs.
Balloon Sources:
Kaymount Consolidated Industries
Box 348
Huntington Station, NY 11746
Kaysam Corp.
Patterson, NJ
Raven Industries
Box 5107
Sioux Falls, SD 57117
(605) 336-2750"
- - - - - - - - - - -
The information above is from an article that appeared in
"Proceedings of the ARRL National Educational Workshop"
(1995 ed.) (Proceedings is available for $12 (plus $4 shipping)
from the ARRL. It contains: "Tips on Recruiting new hams; Teaching
Amateur Radio Courses; Bringing Amateur Radio into the classroom;
and Getting New Hams on the air."
Sincere 73,
Glenn Swanson, KB1GW
Educational Programs Coordinator,
ARRL Educational Activities Department
ARRL Web: http://www.arrl.org/
----------
>From: JBaumgarte
>To: cq-contest
>Subject: balloon verticals
>
>Decided to try this for 160 this season, but have a few questions for
anyone
>who might have tried one.
>
>Picked up some neat "hollow" wire with kevlar liner at Dayton--very light,
>but #14 size. Have the base, radials, etc. pretty well figured out, but
>wonder about the balloon? Local gas supplier wants $35 lease for tank, $35
>for regulator (purchase), and $32 for 121 cu. ft. of helium. (reasonable?)
> Assuming I can find a 3' balloon, how long will one hold the gas?, how
much
>gas is required (simple volume of sphere is not enough--need to know the
>typical pressure), any good ideas on locating a good balloon. Many thanks
>for any suggestions.
>
>John, K0IJL, CAC Dakota Division
>
|