I've seen them on tanks and feel they are a must for airsoft. What is the best way to install and operate a laser pointer into the turret? I've read of a couple using disassembled laser pointers with a seperate switch and AA battery packs, but is it possible to use the pointer connected to the tanks battery pack and power it on and off using your controller? I'm hoping to do this to a 1/24 VSTank Tiger I.

TANKS in advance for your input!

I always thought that you could tie the laser pointer to the firing mechanism so when you fired (and it takes several seconds for the gun to compress the spring) you would identify your targert. This way you don;t have to have a separate power source and you don't have it on all this time *just when you have the tank firing.

Laser diode's need to be current limited to prevent them frying. If you google for "laser pointer power supply" you may find some tips. Apparently the current required to actually "lase" is relatively close the current at which they die.

Most of the cheap laser pointers I've seen limit current with a resistor which is set for the specific number of batteries in the pointer. I think they also count on the fact that the little watch batteries can't supply much current as well (like the cheap LED keylights).
You may be able to get away with a direct swap to AAs, but that may be a little too much and cause the diode to die early, as the AAs can supply more current if the resistor is too low or as temperature varies.

But, you won't be able to hook it up to the tank directly without a good stable voltage regulator to limit the voltage to the same (or ideally slightly below) as the original batteries, and with minimum voltage ripple.
You could also build a current regulator, but I'm not sure how stable it would have to be effective.

Cheers,
D.

You could use a 4 pin- micro relay to separate the high and low power circuits.

I use 3 AAAs to power my laser pointer and use a pico switch on channel 6 of my tx to turn it on or off.

Hello Ern,
Laser pointers vary in voltage requirements. You can easily determine by looking at the batteries that power it. For mine I measures about 10 mA of current draw during operation so you can simply use a resistor to drop the voltage down from the 7.2 V that your battery pack provides to that which the laser requires (mine needed 5 volts). Heres a link I posted about 200 years ago on here.
Perry

http://www.rcuniverse.com/forum/m_58...tm.htm#5841956

To avoid frying the actual Diode Junction, The do NOT drive them with DC. You supply (usualy 3 to 6 ) volts to a very smal pulse circuit which actually drived the diode. It's not like a regular, or high output, LED. Run em on DC without the pulse circuit, or cryogenics, and you will hear a little 'POP', your diode will turn a grey/brown color, and you'll be shopping for another Laser Diode....
Don't ask how I know, or how stupid I am for having to go through it more than once before I put an oscilloscope on my pulse circuit (turned DC converter).......

You can, if you can find them, buy small laser dot assembllies, housed in a brass cylinder, with the pulse circuit inclosed (the brass cylinder makes a nice heat sink). Supplied power is not an issue, as the pulse driver limits what goes to the diode. I've run mine off a 12V carbattery and off a pair of AA batts. Got mine from a parts house in Dallas TX (BG Micro??), but Google is your friend.

Aligning the laser to the gun's point of impact will be a fun project. Remember that laser's light goes in a straighe line from point A to point B. The BB from the Airsoft doesn't.....

Be interresting to see how you come out. Good luck with it.
Splat

Lots of good info...

Thanks to all - eBay has some for a decent price that might work - and they are not in a "pointer" that you have to disassemble.

http://cgi.ebay.com/LASER-DIODE-650-...QQcmdZViewItem

That looks a whole lot like what I have. Becarefull with the power leads to the circuit. I had some trouble with wire breakage. No real problem, but tight soldering!

When you get it/'em (I' suggest one more than the one for each application/tank), hook up power, lay on a flat surface (table), with the dot hitting a dark, flat surface about a foot or more away, roll the diode housing forward and backward and look for the dot's trace drawing a circle. Mark the high point on the front of the laser housing with a sharpie. It will help later when you mount and try to collimate (align or aim) the laser to the canon bore.

good hunting!

Splat

Hey! Good idea splat - Thanks. How do you power yours? Seperate batteries? How switched?

Thanks again