Manual RGB Color Control For TTL DPSS Lasers $150

[markerney]

I need a custom built circuit for my laser projector. I need to be able to push one of (7) push button switches or pads on my control panel to select each color. I already have the ability through my laptop and DAC but I would like manual control also for live ques. Do you have it or can you build it? It should be a fairly easy circuit to design. THERE IS NOTHING LIKE IT ON THE MARKET I CAN FIND! I have been searching for months! Opportunity is knocking! It could definitely be sold to laser hobbyist on ebay! I want the board built with the 7 switches or pads connected (12" wires on each please) with R G B and ground 5v TTL outputs for the lasers. I have the 5v regulated power. I am trying to get something built for about $150 or less but if it looks complicated I will work with you. You make the board and supply only the components and switches or pads. I can mount it in my control panel and connect 5v regulated power to it. The design will belong to you. All I want is the FIRST one for my projector. Simple fact is I need it and do not have the time to design and build it myself. I may just HAVE to build it myself but I am giving this a try first. Let's start making it right here in the USA again! Thank you sincerely for your time and consideration. Mark Erney

[dar303]

You can build it for way less than 150$!
It just takes 7 buttons and some diodes (1N4148) to do it!

Just connect +5V to one contact of the buttons and the diodes to the other.
Red button - diode to R
Green button - diode to G
Blue button - diode to B
Yellow button - diode to R and diode to G
White button - diode to R, to G and to B
...you get it!

You dont need a circuitboard to do it, a box with hole mounted switches and point-to-point wiring for the diodes would work. Then just connect the output wires to a 25 pole DSUB accordning to the ILDA-pinout.

[White-Light]

Excuse me for being thick here as I know little about DMX, but doesn't DMX enable this? I always thought with a DMX board you assigned a slider to each colour so you could do fades through the colours. Surely with TTL or if you assigned a button you'd just get a straight on or off for each?

[markerney]

I do not understand how the diode scheme will work. What will deactivate the previously engaged switch? Wouldn't it work without the diodes? Do they somehow deactivate the previously activated switch? I am definitely an amature when it comes to circuits, components and calculataions. That is why I am offering to pay somebody. A simple solution to my question is a gang of (7) switches that dis-engage any that are depressed when another is engaged but it is almost IMPOSSIBLE to find so far. I have been searching ever since you posted this reply.

As far as the DMX controller .... I am trying to incorporate this into a custom built control panel that will control solenoid and color effects. My computer and DAC controls my galvos. I basically just need the circuit that I can install in my control panel. Thank you again for the help and thank you sincerely for your time and consideration.

Mark Erney

[mixedgas]

You just need a old school laserist to explain.

If you use a DMX output board and a DMX console, its easy, but expensive, you use a receiver like this from Northlight Systems,

http://home.att.net/~northlightsystems/dmx512decoder.htm


I'm sure DAVE here might sell one as well,

I try to be fair to all vendors on things like this

The reason you will not find such a switch are called "SNEAK PATHS". Ie if you have no way of preventing reverse flow back through the switches, you will get combinations of shorts that will defeat you. look at the RGB bus in the picture I have attached and if you can see how it would short out and turn on all three lasers if they were not there.

You would need triple pole, singe throw ganged switches, to do it without the the diodes, and those don't exist. And 8 of them, because blanked lasers are all off, so black becomes a color. IE 3PST would be the notation to describe the switch, and you will NOT find ganged 3PST anyplace. Not a common part

Laser shows are the only thing that use 7 color systems anyways, there is no market, and since it is a simple function, the tradition is to buy your own or let X29 or Pangolin do it for you in software.

The attached circuit is what you need to do what you want manually. YOU WILL NEED THE DIODES, or any button pushed will give you white.
The 470 ohm resistors are for certain low cost lasers that do not have input pull downs and blank when pulled low, not pulled high.
Do not exceed 5V input, PSU not shown.

The term you are looking for is ganged pushbuttons, but with the diodes you don't need them

Some examples:

http://www.surplussales.com/switches/SWPushB-2.html

PArt number SWP) SCH8I is a example of what you would want. Buy bunches of them, because ganged switches wear out fast compared to easily replaceable pushbuttons.

Steve

[Laser Ben]

I like that diagram! One thing I am wondering is if it could be possible to use a set of switches like those used on some devices where you push one in and all of the others pop out.

[-bart-]

Although it's a nice schematic to force the output to certain colors, it is not capable of forcing a displayed frame to be recolored. Al blanking information is destroyed that way. And you lose some intensity because of the voltage drop over the diodes.

I would suggest using the intensity output instead of +5v

[markerney]

Awesome Steve! I am going to breadboard it and see how it acts. What happens if (2) buttons are pushed at the same time? Thank you so much for the replies! This forum is awesome! I really appreciate your time and consideration. I will return the favor to anybody who has any question I may be able to answer concerning satellite communications (my occupation). Thanks again!

[mixedgas]

Although it's a nice schematic to force the output to certain colors, it is not capable of forcing a displayed frame to be recolored. Al blanking information is destroyed that way. And you lose some intensity because of the voltage drop over the diodes.

I would suggest using the intensity output instead of +5v

In my defense, He asked for a beam table style controller. I also did not know if he has TTL lasers, TTL that uses the pulldown to blank, or analog, so I went simple and conservative. Ie no analog multipliers and current sources and recoloring matrix. Besides, he can add three surplus DPDT relays and a comparator and get switchover between graphics and manual with blanking.

Later on, he can add blanking using the circuit below, as a start. Please note I draw simple pictorials for beginners to save them time, for the professional world I use Eagle PCB.
Steve

[mixedgas]

Awesome Steve! I am going to breadboard it and see how it acts. What happens if (2) buttons are pushed at the same time? Thank you so much for the replies! This forum is awesome! I really appreciate your time and consideration. I will return the favor to anybody who has any question I may be able to answer concerning satellite communications (my occupation). Thanks again!

nothing, other then possibly adding a third color.

Steve