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AF6MQ
07-25-2009, 11:45 PM
Hi, just wanted to share a little success i had recently.
i've designed and built a transceiver that uses Fire to
signal in Morse Code. The "receiver" part was not sensitive
enough for the show, so whats missing in the video is
the telescopes and light sensors to see and decode.

main page at http://1sky.com/af6mq/cwir.html

the transmitter part worked well after some timing tweaking,
turns out Fire has a long decay, and i had to adjust the normal
spacing of 1-3-5-7 into 1-5-9-9 or therabouts. but i think
you can get the idea from this,

http://www.youtube.com/watch?v=yVrTZW0hn2s

comments and/or suggestions on light sensor modules or
other options are appreciated.
i was using an OPT101 (pin diode with integrated opamp)
from TI they sampled for free.
the telescope can succesfully "light up my hand" held in
front of the objective lens, but appears to be a very low energy quantum.

anyways, thanks for looking,

73,

AF6MQ

NS8N
07-26-2009, 12:18 AM
I saw a whole lot of dits....but not any dahs....neat project though. Innovative!

AF6MQ
07-26-2009, 05:16 AM
yes, the dahs are only marginally longer than the dits.

in "proper" style, dah = 3 x dit, yes?

in "dont burn all my propane too quick" style,
i tweaked it to more like dah = 1.5 x dit.

overall, the dit length is about 30wpm,
but the spacing was stretched to about 5wpm.

this was so there was more "space" between the fireballs.
mostly i wanted distinct "light" and "dark" in what the
telescope sees. but propane flame has a very slow flame front
and thus a very long "decay" time.

i will be tweaking it more in the future,
to balance between "proper" code and the
above mentioned propane consumption issue.

(too fast draw and the tank freezes dropping the
available vapor pressure to 10 psi, which makes
for very wimpy poofs)

N7IC
07-26-2009, 03:13 PM
Those are some serious smoke signals. :D

KY5U
07-26-2009, 03:23 PM
Can you put on a demo inside my house? I'm behind on my payment and it's well insured.




Disclaimer:

Dear Nationwide,

This is a joke. I am not behind on payments. I like my house. Please laugh. Ha Ha Ha? Ha Ha? Ha? Oh sh#$!

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