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Light Saber Bug Zapper....

Osh

Sep 22, 2012
7
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Sep 22, 2012
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Ok, noob here.... Back story: My folks gave me this tennis racket looking thing that is essentially one of those old back yard bug zappers. Press the button and 5K+ Volts energizes the screens and anything that goes between them is in for a nice surprise. It does wonders to the mosquitoes in the back yard. :D

Anyway, talking to a friend and she mentions would it not be cool if it made light saber sounds... Long story short, I picked up an Ultimate FX Light Saber from a local big box store, did some disassembling and testing and am now down to a dilemma. How do I activate the light saber sound effects? Here's what I've got...

bug zapper: 2 AA batteries, and a momentary push button switch. Push it, the screen is energized. Release and it harmlessly discharges.

light saber: 3 AA batteries, and a momentary push button. Press once and it energizes the blade and starts the sound effect. Press a second time and it shuts everything down. I unsoldered the blade (row of LEDs) and tested it with two AA and the sound is just fine. Also, there is a second 3-way slide switch that turns it off/demo/on.

What I'm looking for is a circuit that when I press the button on the zapper, it sends a momentary signal to the saber (turn on). Release the zapper button and it sends a second momentary signal to the saber (turn off). That signal is a momentary ground on a specific pin on the board. I'm not opposed to replacing the current switch with a SPDT. One issue that could come up is a quick press/release of less than about one second. It takes about that much time to energize the light saber. Any signal to the light saber faster than that is ignored.

Any help would be most appreciated. :)
 

Raven Luni

Oct 15, 2011
798
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Oct 15, 2011
Messages
798
In principle it seems simple enough: when something gets zapped it bridges the connection between the 2 plates. If you can trigger a monostable 555 or something similar that would give you a pulse with length of your choosing to activate the sound.

BUT

You mentioned the voltage was upwards of 5kV. Most circuit components will go the same way as the bugs at those levels. Since you will never be guaranteed a constant or consistent voltage, the only safe approach I can think of is to use an over-engineered resistor divider, probably multi-stage, with some high values to ensure that the voltage is reduced to a very very tiny (practically useless) level which you can then amplify to saturation with a series of transistors (or maybe a single darlington). This will give you safe and level voltage for your trigger.
 

Osh

Sep 22, 2012
7
Joined
Sep 22, 2012
Messages
7
Ohhh, I think I may have explained incorrectly.

When I press the button to energize the screens, I want to sound to start. When I release the button, the sound should stop. So the press should send a pulse and the release should send a second pulse.

I'm not sure what kind of circuit should do that, though a 555 might be in there. I found one circuit, they called it a one touch pulse (attached), but they were touching the wires with their finger tip, so that resistance could be part of it. But when I tried plugging it into Qucs and running a simulation, I either have it wrong, or it doesn't work. The NAND gates were listed as a CMOS 4011, but Qucs doesn't differentiate other than it being a NAND gate.

I'm sure I can figure out some logic with the extra NAND gates on that chip or something else (inverter?) to get the extra pulse when it's released. But the other issue is ensuring the second pulse is at least one second after the first, and a new first pulse (press) is at least one second after the previous second (release).

onetouch.png
 

Osh

Sep 22, 2012
7
Joined
Sep 22, 2012
Messages
7
Clarification, my assumption was that the sound circuit would be separate and isolated from the zapper circuit, except for the power supply. I was hoping to come up with some circuit that would essentially replace the existing (momentary) switch in that light saber with something that was triggered by the same switch from the zapper. If I need to replace the zapper switch with a spdt, I am ok with that, assuming I can find a suitable replacement.

One other possible solution that may work if it tidies things up is some sort of power cut off that activates when the switch is released. This is based on pressing it will send a pulse, and releasing will send a separate pulse, but if the second pulse is quicker than about 1 sec, it is ignored and the sound would just continue when it should be off. Besides the pulse, I am having a problem wrapping my head around that 1 second wait time....
 
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