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Registered Member #211
Joined: Sun Feb 19 2006, 05:33PM
Location:
Posts: 27
Hello all, Halloween is approaching fast and whether you celebrate it or not, tricks and costumes will be aplenty. My question is, using electronics skills and knowledge, what ideas do you have for a gadget/prop for this eventful night? It does not have to be directly related to the classical theme of witches, cauldrons and such, as most Halloween nights are fancy dress that will accept a wide range of costumes and themes, characters from movies, etc.
Example : Wizard's staff Take a long (slightly taller than yourself) branch of a tree, preferably with some weird knots in. Use a dry piece, or dry it out by whatever means you choose. Bore a hole in the 'top' end, poke in an LED, resistor and leads and seat in with epoxy. If you have a glass ornament, piece of gemstone (Quartz shafts work nicely) embed that on top and also epoxy in place. Cut a groove down the branch for the leads. Carefully make a cutout further down for a battery pack and any control electronics and link up to the LED. Electronics could be a flicker system, colour changer, or a shock switch and latch with timer (so when you slam the staff into the ground, the crystal illuminates). Replace any 'holes' with bark or wood from another piece of the same wood and patch it up seamlessly. You are now Gandalf / generic wizard :P
Example : Twisted pumpkin Hollow out a pumpkin as in the traditional method, but instead of using candles to provide lighting, use power LEDs (Or incandescent lamps for their colour rendition) with some flickering electronics. This will reduce the smell, fire hazard and chance of being blown out! Optional evil : PIR activated sound module.
Idea : Using camera flash boards to make a lightening effect. Clock a decade counter {CD4017B}, rigged to an array of relays, in turn connected to the firing contacts on the flash boards. The boards will need very little modification, maybe just bridging the charge switch.
There's only 37 days left so we'll have to get cracking. Regards, Petezel
Registered Member #567
Joined: Tue Mar 06 2007, 10:55AM
Location: Singapore
Posts: 147
...Or you could have electrivity crackling over the top of the staff. I'm not sure how to fit the electronics in (large number of caps, I guess), but I think it's not too hard... Embed a couple thumbtacks in epoxy and connect them to a few capacitors with different capacitances.
Registered Member #952
Joined: Mon Aug 13 2007, 11:07AM
Location: Finland
Posts: 388
Firnagzen wrote ...
...Or you could have electrivity crackling over the top of the staff. I'm not sure how to fit the electronics in (large number of caps, I guess), but I think it's not too hard... Embed a couple thumbtacks in epoxy and connect them to a few capacitors with different capacitances.
Sounds like a nice idea. Maybe you could use an inverter from a camera flash board and photoflash caps of course Then you would need some sort of a triggered spark gap, which is not hard to make either. If done properly, everything should fit inside quite a thin tube.
Some time ago I found this funny circuit and successfully built it. So the leds would flash when you spoke to the microphone.
Registered Member #1497
Joined: Thu May 22 2008, 05:24AM
Location: Toronto, Ontario, Canada
Posts: 801
Add trigger switches for the flash both in the bottom, and in the handle so you can trigger on command or when you smack it on the ground.
As for the crackling electricity, I don't know if there is a safe way to do it since any discharge with enough power to make a snap/crack is also dangerous, but a weakly driven flyback only makes the slight arc and nothing else.
You could always roll a transparency cap and put it across the output of a flyback in parallel so that charging the capacitor gives the flash tube some more kick...
Registered Member #56
Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445
I am spending Halloween at school so probably not many electronics gadgets; although there are supposed to be epic (talking like people partying in the streets for a week) parties in the adjoining neighborhood... If only I was the party type
Registered Member #952
Joined: Mon Aug 13 2007, 11:07AM
Location: Finland
Posts: 388
aonomus wrote ...
As for the crackling electricity, I don't know if there is a safe way to do it since any discharge with enough power to make a snap/crack is also dangerous, but a weakly driven flyback only makes the slight arc and nothing else.
One photoflash cap should not be too dangerous, and will sure create quite a bang! (Who is asking you to put your fingers in the spark gap anyway? )
Another idea which came into my mind, could an exploding wire also work for the crackling effect? The wire should be kinda thin and short, but you would still need about four photoflash caps at least. It could be triggered with a SCR. Also it would have to be exploded far from faces because of the small pieces of molten metal flying in the air.
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Halloween Gadgetry
Then you would need some sort of a triggered spark gap, which is not hard to make either. If done properly, everything should fit inside quite a thin tube.
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