Edwin Johnson wrote:
On 2015-04-24, Ian Jackson wrote:

See
http://www.allsopp.co.uk/

Those are pretty sophisticated balloons. Bet those are similar to the
aerostats the US uses around the Gulf of Mexico for surveillance purposes.
Those are tethered and go up thousands of feet and are marked on our
aeronautical charts. Prices must be high on those, out of the limits of the
average ham here. hi

73 ...Edwin, KD5ZLB
__________________________________________________ __________
"Once you have flown, you will walk the earth with your eyes
turned skyward, for there you have been, there you long to
return."-da Vinci http://www.kd5zlb.org

What you want is something that is a combination of a kite and a balloon
and is more kite than balloon to avoid having to have a lot of helium.

As it need not be man rated, you could make it from tissue, light wood,
with party balloon fillers.

Or if you are feeling adventurous, use hydrogen making sure there are
no sparks at the end of your antenna.


--
Jim Pennino

On Sat, 25 Apr 2015 14:17:46 +0000 (UTC), Edwin Johnson
wrote:

On 2015-04-24, Ian Jackson wrote:

See
http://www.allsopp.co.uk/

Those are pretty sophisticated balloons. Bet those are similar to the
aerostats the US uses around the Gulf of Mexico for surveillance purposes.
Those are tethered and go up thousands of feet and are marked on our
aeronautical charts. Prices must be high on those, out of the limits of the
average ham here. hi

73 ...Edwin, KD5ZLB

Yeah, but not too horrible. See price list at:
http://www.allsopp.co.uk/index.php?mod=page&id_pag=35
My guess(tm) on the weight of a 1/4 wave 160 meter monopole was 464
grams without the weight of the balloon, insulators, and whatever else
might be needed. Looking at the chart, I could get a "Skyhook" model,
that would lift 800 grams with no wind, for $760 excluding VAT, duty,
and shipping. You decide if having the loudest signal on 160 meters
is worth the expense.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

"Ian Jackson" wrote in message
...
In message , Edwin Johnson
writes
On 2015-04-23, Oregonian Haruspex wrote:
On 2015-04-18 08:38:31 +0000, gareth said:

How about a tethered helium balloon instead? This way you don't have
to worry about powering the thing. Bell wire will handle 100 watts all
day without turning into smoke.

This sounds like a neat experiment, which one of our members tried on
field
day. There are several problems in the electrical side of things, but more
importantly on the physical side. As you rise in altitude the wind speed
will increase, generally speaking, and perhaps change directions. If the
day
is completely calm especialy above the tree line, say 100-200ft, then the
balloon will remain straight up. But launching a balloon in a 10mph wind,
which becomes 15-20mph above the tree line, leads to interesting
developments with the tether wire/cord definitely sloping and perhaps
being
pushed into surrounding objects such as trees, power lines (eh gads!)
which
can cause it to break or other things. So you need plenty of space with
few
impediments for the balloon to catch on as it ascends. You certainly can't
predict a perfectly calm day, so this can be an unpredictable venture. ha

See
http://www.allsopp.co.uk/
Is there any practical way to put back the Helium in the bottle in case of
success
or not too complete failure ?
This will surely lower the cost of experimentation.

On Sat, 25 Apr 2015 16:42:02 +0200, bilou wrote:

"Ian Jackson" wrote in message
...
In message , Edwin Johnson
writes
On 2015-04-23, Oregonian Haruspex wrote:
On 2015-04-18 08:38:31 +0000, gareth said:

How about a tethered helium balloon instead? This way you don't have
to worry about powering the thing. Bell wire will handle 100 watts
all day without turning into smoke.

This sounds like a neat experiment, which one of our members tried on
field day. There are several problems in the electrical side of things,
but more importantly on the physical side. As you rise in altitude the
wind speed will increase, generally speaking, and perhaps change
directions. If the day is completely calm especialy above the tree
line, say 100-200ft, then the balloon will remain straight up. But
launching a balloon in a 10mph wind, which becomes 15-20mph above the
tree line, leads to interesting developments with the tether wire/cord
definitely sloping and perhaps being pushed into surrounding objects
such as trees, power lines (eh gads!) which can cause it to break or
other things. So you need plenty of space with few impediments for the
balloon to catch on as it ascends. You certainly can't predict a
perfectly calm day, so this can be an unpredictable venture. ha

See http://www.allsopp.co.uk/
Is there any practical way to put back the Helium in the bottle in case
of success
or not too complete failure ?
This will surely lower the cost of experimentation.

The cost of Helium will continue to rise. Once used, it is effectively
gone for ever as it will leave planet Earth to mix with the rest of the
Helium in space. What we have now is from reserves that come from nuclear
reactions within our planet, and that is all we have got!

Perhaps it's time for us to be less flippant over using this
irreplaceable wonder element!