h a l f b a k e r yNot just a think tank. An entire army of think.
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A fairly simple device, effectively a microphone with the output modulating a torch/flashlight for sending, and a light detector wired to a speaker for receiving. Could come in both one and two-part form-factors.
Handy for talking to your friends, who happen to be some distance away.
There are
various details, which are all easily dealt with.
The torch is probably LED-based; LEDs seem to be getting very much better and cheaper recently. These are either 'on' or 'off'. But they can switch very quickly, so we can describe the sound as pulses. The encoding is very basic, published and 'open'.
It may help reduce noise if the detector were to be specific to a certain wavelength. The transmitter can then use that to maximise efficiency. There is probably a 'best' colour for this purpose which is a compromise between LED efficiency, atmospheric transmittance and ease of detection. If made with lasers my guess would be green, but using lasers may have safety and regulatory hurdles to overcome.
Alternatively, one could have several different 'channels' utilising different frequencies.
[link]
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It should have an option to translate to and from morse
code |
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if( (detector == camera) && (field_of_view < 10degrees) && (focus ==
AUTO) && (sensor == COLOUR) && (distance < SPITTING) &&
(price_of_camera > YOUR_MONTHLY_INCOME) && (flying_pigs_seen
== TRUE))
{
it_might_just_work = TRUE ;
}
else
{
it_might_just_work = FALSE ;
}
return(VOID); |
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If you could somehow construct a type of thin glass wire which could carry the light straight from the source to the detector, you could dispense with the line-of-sight part. You could be on to something here. |
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//If you could somehow construct a type of thin glass wire which could carry the light straight from the source to the detector, you could dispense with the line-of-sight part. You could be on to something here.// |
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Heh, then we'd have a high-tech version of the two cans & a piece of string toy. |
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//if( (detector == camera) && (field_of_view < 10degrees) && (focus = AUTO) && (sensor == COLOUR) && (distance < SPITTING) && (price_of_camera > YOUR_MONTHLY_INCOME) && (flying_pigs_seen == TRUE))// |
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oh, the hazards of pseudocode. You've just set focus to AUTO. And I can get closer to success by losing my job and taking hallucinogens.
Actually, since one can see even a faint light from a distance, I'm not convinced it's impractical. I'm not even sure the receiver would have to be a camera. |
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//you could dispense with the line-of-sight part. |
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Hmm, just kicking around an idea, if you were to attach a photo-electric cell to a copper wire, then shine the LED on it, then I believe it might be possible to transmit the message quite a long way, possibly? |
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Of course, the more satisfying version would be to shine the LED light into an internally mirrored-surfaced miniature Klein bottle, which is then strapped to a pigeon, the light (and so the speech) to be extracted at the other end. |
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Similar to something baked -- look up "lasercom" |
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//You've just set focus to AUTO // |
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//since one can see even a faint light from a distance, I'm not
convinced it's impractical. I'm not even sure the receiver would have
to be a camera // |
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A simple photocell works on average illumination. The change in
illumination of a single flashing LED is insufficient to change the
signal above the discrimination threshold given all other possible
causes of such a change, unless it's a very dark night. |
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An eye (= camera) is a very different device to a simple photodetector. |
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[8th], did you just use an if statement to test a
boolean value then assign that same boolean value to a
variable? Do you get paid by the line of code or
something? |
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And not only that, but the code doesn't actually do
anything, unless it_might_just_work is a global
variable. Why not just return the result of the test? |
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//A simple photocell works on average illumination. The change in illumination of a single flashing LED is insufficient to change the signal above the discrimination threshold given all other possible causes of such a change, unless it's a very dark night.// |
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Good point. We do need to have a decent solid angle to be able to reliably pickup the feed.
Digital cameras do seem to be pretty cheap now - looking at webcams, for instance. We probably don't need all that many pixels, but we do need a high refresh rate. That probably means it needs to be custom for the purpose. |
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Although... It would still work at night anyway. |
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// [8th], did you just use an if statement to test a boolean value then
assign that same boolean value to a variable? // |
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No, we assigned a global static to an integer, but then tested the
boolean outcome ... where the assignment should actually have been
an equality comparison. |
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// Do you get paid by the line of code or something? // |
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No, by the number of pc's added to the bot-net. |
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// but the code doesn't actually do anything, unless
it_might_just_work is a global variable. // |
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Yes, it is. Do you want us to cut and paste the .h files and the make file
? |
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// Why not just return the result of the test? // |
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Because it's better to reserve the return() lvalue for an error/status
code in case the function is subsequent expanded. |
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You could build the receiver into a pair of
binoculars. Just have the photocell flipped in to
one side of the bins. You could look through one
eyepiece to locate the light source, and the other
eyepiece would act as the detector. That ought
to work. |
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Plus you could modulate the LED at a certain high
frequency and filter the receiver, making it a lot
easier to extract the LED's signal from other
(possibly varying) light sources. |
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Or you could go to Aldi or Lidl and buy a pair of PMR446 handsets for
twenty quid ... they give you batteries, too. |
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Or you could pick up a couple of discarded St George's crosses for
free from the nearest gutter and learn semaphore... |
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Or you could just walk over there and transfer the message using
modulated sound waves. |
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But that might be just a bit too practical. |
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Do the Borg get a lot of party invites, [8th]? |
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Only from you, the Intercalary Twin, and your Uncle-in-law Ko Man
Chu. |
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Plus the usual "New Year Party" one from the boy Branson, but we just
bin those. |
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Very wise. If, just once, he wouldn't get drunk and
whip out his harmonica... |
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By the way, Great Aunt Halva sends her regards, and
said to thank you for the cheroots. |
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Awww, she's such a nice old lady. |
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By the way, is it likely to be "Bring your own goat" again at Samhain
this year ? We felt a bit left out, to be honest, although the bonfire was, as usual, beyond reproach, and the idea of putting live piranha in the
apple-bobbing tub was truly inspired, |
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Tell Sturton to try rubbing it with a mixture of bicarbonate of soda and
female weasel urine, It may not help reduce the swelling, but he is
likely to make some interesting new friends, probably mostly male
weasels, but then in his situation he can't afford to be choosy. |
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Knowing Sturton, he has no intention
whatsoeveratall of reducing the swelling. In fact,
since we share a tailor, I happen to know that he
has had a special bathrobe made to accommodate
it. If possible, avoid being in front of him in
queues. |
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We are doing away with the goat theme entirely
this Samhain. Aunt Halva has agreed to open the
festivities in the nor' nor' east courtyard, and you
know how she is with her allergies. There will,
however, still be the swine-lap and hoop-the-seal.
Bring the usual gear, and tell your loaders to
expect a long night. |
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Possibly something could be done with two small(ish) animals like amoeba and weapon salve? Also needs two microscopes, to see the reactions of the amoeba. |
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Simply lightly stab the amoeba, then switch needles with your contact, then use the smartphone to send a small electric shock to the needle...and so on. |
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Don't forget to label the needles, as it's soooo embarrassing if you swap the wrong ones. |
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bot nets as well as humans. I bet they have plans for
controlling Cthulhu, Hypnotoad, zombiies, and insects
as well just in case. |
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