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Help request for building functioning movie prop sci fi "laser gun"

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Hello.

I am working on one of many projects where I need some tech help in the design.

I have started with a typical handheld barcode scanner (desktop model), which no longer functions, and I am "feinberging" it to make it into a movie prop laser gun with functioning lights.
I have LED's for the "setting indicator" light on the top and for the "emitter", as well as a rheostat to turn the device on and off and to control the speed of the blinking light of the "setting indicator", along with a momentary switch to act as the "trigger" for the emitter lights.

What I want to do is set the device up to do the following:
have the setting light blink at a variety of speeds with multiple emitters coming on at various settings (maximum of six emitters in 3 different colors - red - yellow - green).

Ideally, that is what it would be set to do. One color as the low level, two colors at the intermediate level and all three colors at maximum.

Alternatively, if that is not possible, then simply having the emitters all pulse together at different settings independent of the status indicator light when the trigger switch is depressed, or in synch with the status indicator if it is not possible to make it blink independently on it's own, secondary circuit when the trigger is activated.

My problem is that my skills in electronics are horribly lacking for such a project and I do not wish to go out and buy a bunch of strobe components that may or may not fit in order to make this work (this is a very low budget project). I have the skills to do the assembly, with many decades of model building and my dad teaching me how to solder electronics many years ago, but I lack any functional knowledge of how to make the circuit board layout and all for something as complex as this.

I have a basic (rough) diagram of the device that I am modifying (side and top views - battery pack to be added) and, as I said, it is a commercially available barcode scanner (model LS 2208) that my day job was tossing because it no longer works, so none of the original guts will work for this project anyway.

I plan on powering the device with 4 AAA batteries, so that will give an idea of how much power the system has to manage.

Any advice, circuit diagrams and recommended components would be appreciated.
**broken link removed**
 
.... and for safety's sake I wouldn't use a laser pointer!
 
Here is the rough drawing of what I am starting with. The trigger mechanism will be replaced by a simple push button switch and I plan on adding to the rear to accommodate the battery pack. The current drawing shows the extended front that I plan to add to the original scanner that I am building this prop from.

using a laser pointer is out of the question due to safety issues as well as the fact that this is going to be a movie prop. Laser effects will be added in post production. All I will need is the lights to work the way that I need them to.
 

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I got a little lost on how you want it to work .
An adjustment to fake a power setting indicated by 3 lights?

You understand it correctly.

As I said, this is supposed to be a movie prop to be used in a film project that I have in the works. The three lights will be in the emitter end and the blinking "power setting" light will be separate and change blink speed (or color) as the setting is changed. I currently have two of these, initially as prototypes, and wish to make them both the same with plans on replicating them for the purpose of the film
 
OK, I think I got it.

Here is a 3 position switch:
https://www.mouser.com/ds/2/60/A_Rotary_30juyl14-38283.pdf
This is how I think you want it:
switch setting one - slow blink on a red led in the grip or back of the gun.
When trigger is pulled 1 or 2 green leds turn on.
switch setting 2 - blinks faster, when trigger is pulled green and yellow leds light
switch setting 3 - fast blink rate - all three leds light when trigger is depressed.
Not to hard to do if I understand it correctly.
 
Another safety issue. A blink rate ~6Hz-8Hz should be avoided, since epileptic seizures can be triggered by flashing lights at about those frequencies in susceptible people.
 
Another safety issue. A blink rate ~6Hz-8Hz should be avoided, since epileptic seizures can be triggered by flashing lights at about those frequencies in susceptible people.

I hadn't thought of that. Thanks.
Though, I don't think that will be a serious issue as it is only a small (1/8" x 1/4") indicator light. I will keep your recommendation in mind though, when I set the blink rate of the indicator light.
 
OK, I think I got it.

Here is a 3 position switch:
https://www.mouser.com/ds/2/60/A_Rotary_30juyl14-38283.pdf
This is how I think you want it:
switch setting one - slow blink on a red led in the grip or back of the gun.
When trigger is pulled 1 or 2 green leds turn on.
switch setting 2 - blinks faster, when trigger is pulled green and yellow leds light
switch setting 3 - fast blink rate - all three leds light when trigger is depressed.
Not to hard to do if I understand it correctly.

That is exactly what I need to use and have it do.

I only took a cursory look at the specs for the switch that you recommend, but I did not notice any dimensions on the switch itself. Will it be small enough to fit in the base of a handgrip that is only big enough to accommodate a switch that is about half an inch wide?
I already picked up a rheostat type switch (mini volume control) from Radio Shack that is the correct size, but as I said, it is a rheostat type (not my ideal choice, but I didn't see any like you have suggested). It looks like I will have to return that one and get a different one.

Knowing that, now all I need is a schematic. As I think I said earlier, my schematic design skills are almost nonexistent and while I could go to my dad, a former USAF radar repair tech, his electronics knowledge is about 60 years out of date as he hasn't actually used that tech skill since I was a kid in the 60's.

It isn't that I'm stupid, just that I lack the level of skill required to design the bloody thing. Building is the easy part.

Would you happen to know of anyplace that might have a circuit design already made that can work for this?

Again, any help is greatly appreciated.
 
That one is about an inch in diameter. Let me see if I can find a smaller one. Using the switch make the circuit much easier as it can change the blink rate and set the power at the same time.
Give me a little bit and I can make you a circuit.
Edit:
Having a little trouble finding a smaller one. This is what I was thinking. Do you think it would fit?
About 1" diam for the switch, but the knob could be smaller. I think we could make the thicknes about 3/4 inch.
 

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Yes, 1/2 inch square.

Here is the basic circuit, It still needs work on the component values, but will give you an idea.
Think you can build it?
 

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Yes, 1/2 inch square.

Here is the basic circuit, It still needs work on the component values, but will give you an idea.
Think you can build it?

Wow, that is amazing. I believe that I can make that. Building is the easy part.
I'll need to brush up a little on reading schematics, but I should be doing that anyway.

If this works out I am definitely going to need your info to make sure that you get credit as part of the props team (and payment if I make any money on any project that I use this on).
 
OK. Good. I'll tweek it to get the values right. I just set it up to simulate it. I have honey dos tomorrow, but pretty soon.
 
OK, here we go.
If you want to message me your e-mail I'll make a parts list at Mouser so you can see all the data sheets & pricing and order if you like.
I also attached the simulation file in case someone else has some ideas they would like to try out.
 

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OK, here we go.
If you want to message me your e-mail I'll make a parts list at Mouser so you can see all the data sheets & pricing and order if you like.
I also attached the simulation file in case someone else has some ideas they would like to try out.

Sorry it took so long to get back to you on this. Editing jobs and all.

I tried to look at the .asc file, but I have no programs that can open it.

As to messaging my e-mail, I don't know if it's me, but I cannot find the way to send private messages on here. Maybe I'm just tired, but I have looked all over the site fror it and cannot find it.
 
.asc is an LTSPICE (free) file www.linear.com It's a circuit simulator.

PM's are called Conversations. Hover over your username at the top right of the page. It's in the second column of options.
 
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