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Manual colors with white fusion?

zaery

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I really, really want a manual control on my white fusion, has anyone thought of using varistors instead of buttons? As a side-note, would it be even more cool to make it so that there's a switch that lets you switch between manual controls and FML driven controls?

Edt: i got the wrong name, what's the name for the little thing that looks like a button, like on old TV volume controls, it clicks on, and you can turn it further to make it louder? It should go from 0 to infinite ohms.
 
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zero to infinite??

There called potentiometers (pot) and the highest value they can possibly go is 0-the rated value

100 ohm pot = 100 ohm max, 1K pot = 1K max, 10k, 100k, 1meg=1 meg max.

They are available in "linear taper" meaning a "perfect" linear scale, and "audio taper" optimized for volume and tone controls in amplifiers.

A potentiometer is a manually adjustable resistor. The way this device works is relatively simple. One terminal of the potentiometer is connected to a power source. Another is hooked up to ground (a point with no voltage or resistance and which serves as a neutral reference point), while the third terminal runs across a strip of resistive material. This resistive strip generally has a low resistance at one end; its resistance gradually increases to a maximum resistance at the other end. The third terminal serves as the connection between the power source and ground, and is usually interfaced to the user by means of a knob or lever. The user can adjust the position of the third terminal along the resistive strip in order to manually increase or decrease resistance. By controlling resistance, a potentiometer can determine how much current flows through a circuit. When used to regulate current, the potentiometer is limited by the maximum resistivity of the strip.
 
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You should never adjust a potentiometer on a running laser. Sometimes the wiper comes off the track as it's being turned, and even if it only goes to 0ohms for a hundredth of a second, your laser is toast.

The way the FML driver works is by using PWM (Pulse Width Modulation), where it's constantly turning the laser on and off hundreds of times per second, and by leaving it on for a millisecond longer each time, it controls the overall power of the laser. FML's PWM controller is hacked together out of a prebuilt commercial LED controller, so we don't have the source code, and we can't modify it to do what we want, we're stuck with the programs it comes with. If someone were to rewrite that chip from scratch, we'd be able to control it however we want. I've been toying with the idea of that myself lately, I'm thinking of buying an arduino to practice on. I'd like to make an open source version of the chip used in FML's driver, it's just going to take a bit of work. My assembly language programming is rusty.
 
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You should never adjust a potentiometer on a running laser. Sometimes the wiper comes off the track as it's being turned, and even if it only goes to 0ohms for a hundredth of a second, your laser is toast.

The way the FML driver works is by using PWM (Pulse Width Modulation), where it's constantly turning the laser on and off hundreds of times per second, and by leaving it on for a millisecond longer each time, it controls the overall power of the laser. FML's PWM controller is hacked together out of a prebuilt commercial LED controller, so we don't have the source code, and we can't modify it to do what we want, we're stuck with the programs it comes with. If someone were to rewrite that chip from scratch, we'd be able to control it however we want. I've been toying with the idea of that myself lately, I'm thinking of buying an arduino to practice on. I'd like to make an open source version of the chip used in FML's driver, it's just going to take a bit of work. My assembly language programming is rusty.
That would be awesome! I myself am a bit intimidated by pic programming and don't plan on getting into it any time soon :(.

However the my driver has the colour adjustment pots and can be adjusted whenever you want to make any colour you want (within the colour gamut). Just got to the white marker in the program.
 

zaery

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zero to infinite??

Yup, 0 = fully on, infinity = fully off.

And Pseudolobster, would adjusting a pot really kill a diode? Even if it has a flexdrive? I would never run a laser again without a driver (I did once, it was kipkay's fault, i was young and ignorant)

FML: I want to have manual controls on the outside, instead of buttons, or potentiometers that look hard to turn (looks like they need a flat-head screwdriver?)

A friend of mine says that I'm looking for a varistor, but google images says that they don't have a dial.

Addendum: Like this:
7%20color25.jpg

But with knobs instead of buttons.
 
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Varistors are the same thing as potentiometers, and they come in all forms. Some are sliders, others are dials, they come in all shapes and sizes. The concept is the same for all of them though, it's a conductive wiper that slides across a resistive track, allowing you to choose the resistance.

I'm not sure they'd all have problems, maybe some of them are well built enough that you could reliably use them directly on a laser, but for the most part, they're not meant for high precision electronics... Usually when you turn (or slide) them they introduce noise on the line, and they can even cut in and out as they're being adjusted.. Ever notice on some old radios it would make crackling noises as you changed the volume? Yeah, that would kill a laser pretty efficiently.

FML says though, that his driver already has connections for potentiometers, which will vary the pulse width, safely changing the power of the laser... So it seems like that problem has been solved already. The way that works is instead of the pot directly controlling the output of the driver, it controls the chip which controls the driver.
 

ZRTMWA

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Your best bet would just be to hook the FML driver up with switches first:

dfsaedrgfraes.jpg


Then add pots. It sounds like this is what you are asking for but just with pots that are larger or have more user friendly buttons? Just buy a pot that has a control knob/dial. They can be found here:

Potentiometer.com Stock and Custom Potentiometers
 

zaery

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I was mainly looking for one that would go from 0 ohms all the way to infinite resistance, but I suppose a switch and pot in series would do the job.
 
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Infinite resistance would be an open circuit (disconnected).
 
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Varistors are the same thing as potentiometers, and they come in all forms. Some are sliders, others are dials, they come in all shapes and sizes. The concept is the same for all of them though, it's a conductive wiper that slides across a resistive track, allowing you to choose the resistance.

I'm not sure they'd all have problems, maybe some of them are well built enough that you could reliably use them directly on a laser, but for the most part, they're not meant for high precision electronics... Usually when you turn (or slide) them they introduce noise on the line, and they can even cut in and out as they're being adjusted.. Ever notice on some old radios it would make crackling noises as you changed the volume? Yeah, that would kill a laser pretty efficiently.

FML says though, that his driver already has connections for potentiometers, which will vary the pulse width, safely changing the power of the laser... So it seems like that problem has been solved already. The way that works is instead of the pot directly controlling the output of the driver, it controls the chip which controls the driver.
The pots do directly change the current. It is perfectly safe though, any spikes that may occur are shorted to ground via the disk caps. And if the pot would cut out, the current would go to the lowest possible current. And the driver can't over-drive the diodes with too much current either.
 

csa1

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hi, i am carl inventor, recently i have founded something new , it will be a great hit in lightning world , however since i am only an optics man and not an laserman i am seeking for someone who s willing to participate in my project , what i need is a white laser , the deal will be as follows , you will borough me an working white laser for the project , as i finally sell this invention i will pay you 1 procent of what i get , and that coulfd be somwhere between 1 and 2 million dollars , so you get 10000 to 20000 dollar straight away as i have selled , so who will send me an private mail , whit his proposal , it doesnt stink , you can find me on the espacenet.com under carolus sande , i hear from you .... tnx
 
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Something smells fishy. You expect one of use to build you a white laser which cost hundreds of dollars, and a ton of effort, just to get paid "if" your invention gets sold for only so much money? I can build you one, but I want guaranteed money. You can pm me.
 

csa1

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well , thats not so , as a matter of fact i can explain the reason for all this , earlyer at the end of 2009 , i had a budget for the complete project , 600 dollar for a small white fusion laser , and after i did payed a tyler ( dark) 700 dollars in advance , i did till now heard nothing more from him so the money is stolen from me , so ....no budget anymore for only the laser , thats why i came with this idea , so if someone dears , i will ofcourse pay the shipping coast , and after the project returning the white laser , i think its a fair deal .... carlo
 




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