A TV CAMERA ON THE BELLY OF
A GOELAND

Some
additional informations about our activities:
We used a
seagull, (Jojo) like carrier for our mini video
transmitter on 1255 MHz. The experiment took place only
three times with very variable results. Here are the
reasons:
Jojo is not
completely tamed. I would even say that it is perfectly
wild though very accustomed with us.

1. History
:
Two years
ago, this bird, during its tours used to plunder my
dustbin. It even took food from our hands. After thaty,
it disappeared, and a few days later, returned, always
with the only idea "eating".
A few months
ago, I had produced a very small ATV transmitter on 1255
MHz with 100 mW output power, and a delirious idea came
to me. My dog, a small poodle,wasfrequently running away,
and I had theproject to equip it with a small beacon to
find it. And why not withe the HF camera ?
And more
fantastic, why not equip the seagull too?
It has 1,5
meter of wingspan and can doubtless carry a 1 Kilogram
fish in the airs, then, a fortiori it can take 300 Grams
of hardware very well.

2. First
experiment :
Capture of
the animal with some pecks, and Jojo is equipped with
rubber bands at the first time, to retain the camera, and
it is released. We had to release it several times,
because it had decided to come back to the fishes we had
by us to recover the camera. Good, after many tests, it
endly fly away. To about thirty meters at the beginning.
For the
reception, we used a small parabola 60 cm in diameter,
illuminated by a horizontal dipole, and it was necessary
to permanently point towards the bird. A broadcast
satellite receiver (900 MHz with 2,4 Ghz) and a small B/W
television se. The pictures are excellent, but very bad
at the same time. The antenna on the transmitter is a
small wire 6 cm long, and changes of polarization make
fading on the received signal. We had no video tape
recorder functioning with 12 Volts, but the pictures are
very impressive
The feeling
of flying is very strong but we cannot drive " the
machine "!.
It was
relatively easy to recoverf the hardware,
"Jojo" inevitably returns to us as soon as a
fish or even a simple rag is showed to him. But it should
then be caught, without wounding it, and especially
recover the transmitter. That takes time and patience.
3. Second
experiment :
Obviously,
after the first experiment, we had released our carrier.
It came back a few days later. I was alone, without
anybody to help me. On the other hand I was ready with a
new system for the camera: with adhesive to stick the
camera directly to Jojo's breast making easier
installation and recovery of the hardware.
But Jojo is
suspicious nows, it knows what we intend with it...
The receiver
is in the shack, the antenna is a quarter wave with a
BFR90 preamp and a satellite receiver (Thundered XL 200
C), a PC with a video card is ready for acquisition of
the pictures.
But the
inversions of polarizations are still present.
The pictures
are not sensational, the fields around the QRA...viewfrom
a few meters high. In fact, what can be seen from the
hills in the vicinity.
4. Third
experiment :
Now,everything
is ready, men, hardware, vehicles.
The place:
the edge of sea. The transport of Jojo, in a paperboard
The flight
proceeded well... at the beginning.
Seeing that
there is nothing to eat Jojo get an offing! Horror... and
the hardware? The camera sends pictures (approximately 20
minutes autonomy ) but the bird is very high and the
quality of optics do not make it possible to get high
quality pictures.But it's better than noything. The
recording takes place in an old portable video tape
recorder bought a few Francs in "a deposit sale
" and which failed very quickly. The tape was
crumpled, and had to be cut to extract it, a few
centimeters only will be saved.
The recovery
of Jojo was not easy. We thought it definitively gone.
And then it came back, the camera was wet but always hung
to its feathers.
We had not
thought he could land on the sea...

5. Conclusion
:
The seagull
is undoubtedly an amusing experiment and doubtless
transportable on other types of birds.
A goose or an
eagle for example. At this time, Jojo is absent. It is
laying time for the seagulls and may be were we wrong,
Jojo is possibly a lady what would explain its absence.
Will we rename it " Gigi ", who knows?
I have in
construction a 100 mW transmitter a 10 Grams camera ,
objective included.
The whole,
transmitter, camera and battery, enter in a matchbox.
F6dtl -
George Bellezit
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