Hey guys!
I'm trying to build a basic lasertag setup w/ tagger and receiver, operating in the 40khz range.
All of the 555 timer based circuits I checked out online specifically for 40khz IR emitters required a potentiometer, which I did not want to use due to tuning and added variation.
So I found an online calculator and played with the values until it displayed 40khz frequency. Here are the parts I wound up using:
capacitors: .1pf, .001pf
resistors: 12K, 12K (separate 10K + 1K + 1K, linked together for each) *
555 timer
TASL6100 Infrared LED
* also a current-limiting resistor between the LED and 555 output
This is operated by a push-button switch. All housed in a SCH. 40 PVC gun. As this is a prototype gun, I have the end set up to where I can swap out couplers and try different diameter (and focal length) lenses. The LED is held in a bezel, which is inside a rubber grommet, which fits very snugly into the barrel.
I have a section of pipe that is marked with the focal lengths of various lenses that I use to slide the LED unit back in the barel, until the line matches where the lens will be.
The target (which is velcro'd to the players hat) is based on the Vishay 40khz demod (receiver), capacitor, and resistor. Output goes to a piezzo buzzer now, but I'm planning to add a pager motor to the scenario for a bit of feedback when the player is hit.
The tagger and emitter work. I've tested it with lenses and currently get decent range (and expect more with different lenses and better focusing).
Here are the questions:
#1 - How do I limit the transmitter to, say, .5 or .25 second pulses? Currently it emits as long as the button is held down. I've looked into 555 monostable one-shot circuits, but they don't provide for specific frequency outputs.
#2 - I'd like to use perhaps a counter circuit attached to the receiver (plan to build several of these receivers and hook together in series... would be worn on a headband) to keep up with hits. After 5 hits or so, the gun wouldn't work (which requires some type of setup between the gun and sensors to disable the gun. Phone line/jack connections or 1/8" audio connections, I'm thinking... just don't know the circuitry side of it)
#3 - I removed the resistor in front of the LED to drive it a bit higher. I figure this is safe since I'm not holding the trigger down (and hopefully can find a solution to question #1), but want to know if it greatly decreases life expectancy of the LED.
This is VERY basic stuff, I know, but we aren't currenty going for the more advanced scoring, player names, game types, etc, etc. and want just a basic 5-hits-and-you're-out last man standing type deal. THEN I want to move into other stuff like perhaps PIC programming and maybe **broken link removed** circuitry.
Just getting my feet wet at the moment.
Thanks for any help you guys can offer!
I'm trying to build a basic lasertag setup w/ tagger and receiver, operating in the 40khz range.
All of the 555 timer based circuits I checked out online specifically for 40khz IR emitters required a potentiometer, which I did not want to use due to tuning and added variation.
So I found an online calculator and played with the values until it displayed 40khz frequency. Here are the parts I wound up using:
capacitors: .1pf, .001pf
resistors: 12K, 12K (separate 10K + 1K + 1K, linked together for each) *
555 timer
TASL6100 Infrared LED
* also a current-limiting resistor between the LED and 555 output
This is operated by a push-button switch. All housed in a SCH. 40 PVC gun. As this is a prototype gun, I have the end set up to where I can swap out couplers and try different diameter (and focal length) lenses. The LED is held in a bezel, which is inside a rubber grommet, which fits very snugly into the barrel.
I have a section of pipe that is marked with the focal lengths of various lenses that I use to slide the LED unit back in the barel, until the line matches where the lens will be.
The target (which is velcro'd to the players hat) is based on the Vishay 40khz demod (receiver), capacitor, and resistor. Output goes to a piezzo buzzer now, but I'm planning to add a pager motor to the scenario for a bit of feedback when the player is hit.
The tagger and emitter work. I've tested it with lenses and currently get decent range (and expect more with different lenses and better focusing).
Here are the questions:
#1 - How do I limit the transmitter to, say, .5 or .25 second pulses? Currently it emits as long as the button is held down. I've looked into 555 monostable one-shot circuits, but they don't provide for specific frequency outputs.
#2 - I'd like to use perhaps a counter circuit attached to the receiver (plan to build several of these receivers and hook together in series... would be worn on a headband) to keep up with hits. After 5 hits or so, the gun wouldn't work (which requires some type of setup between the gun and sensors to disable the gun. Phone line/jack connections or 1/8" audio connections, I'm thinking... just don't know the circuitry side of it)
#3 - I removed the resistor in front of the LED to drive it a bit higher. I figure this is safe since I'm not holding the trigger down (and hopefully can find a solution to question #1), but want to know if it greatly decreases life expectancy of the LED.
This is VERY basic stuff, I know, but we aren't currenty going for the more advanced scoring, player names, game types, etc, etc. and want just a basic 5-hits-and-you're-out last man standing type deal. THEN I want to move into other stuff like perhaps PIC programming and maybe **broken link removed** circuitry.
Just getting my feet wet at the moment.
Thanks for any help you guys can offer!