xpyttl wrote:

Looking at the Dave Benson schematics is a good suggestion ... I would
also look at Elecraft who also has manuals online with schematics. I would
also
look at the hfpacker amp (www.hfprojects.com). This was a project ran a
couple years ago to build an amp to basically take the QRP rigs in the 2.5
watt range to 30 watts or so. The design actually could do it with a watt
of drive but they put an attenuator in the front to allow flexibility with
different rigs that didn't have completely adjustable output power.

But I also have to ask the same question Tom asks. 80 is a noisy band,
and
one that demands large antennas. To get past the noise you need power,
and
that adds a lot of weight. Don't forget, you not only have the amp to
carry around, but you gotta carry the DC to run all this, too.

If you are line of sight, then you can go very high in frequency, but
certainly in the higher parts of the HF spectrum, the antennas are more
manageable and the bands are quieter, which means power is less of an
issue. You could even go to VHF but then the whole construction thing
becomes more challenging.

But then, if you are looking for a 100-200 mile path, then 80 probably is
the ticket, but you're going to have to constrain your playing to days
when
the A index is low. Indeed, I would suspect you would want to be
balooning
in the daylight - precisely when 80 is very noisy. So you better be
paying close attention to the propagation reports if you want to hear your
baloon.

..

"Tom Bruhns" wrote in message
m...
Shouldn't be too difficult to come up with the brute-force answer, but
I have to ask: Why?

I was a little distracted by the main path of the conversation that we were
having so I didn't ask at that time why they wanted 80 meters for a beacon
from that high. I also realize that it is going to take a fair amount of
battery to keep this thing going for any period of time.

These people do a lot with GPS. Maybe they are hoping to pass GPS location
data to the ground crew after the payload lands so that they can go right
to it and pick it up. I have no idea what they are doing with antenna ideas
or anything like that.

Now, what was his phone number? :-)

In the mean time thanks for the information. I will get to looking at it
and pass it on.

Al Butler
ka0ies