[I'm a bit at a loss as to what to do considering we already have many projects in progress but this is the start of the blog ... I was thinking that any previous updates will end up on the site, or on their own page, but that doesn't really make sense (mostly because I'm trying to fully transition over to the blog).]
I guess a recap will have to do.
- Stage 0 was working up the initial idea to make the lasertag project
- Stage 1 was mainly a proof of concept by me to see if we could get a 30kHz receiver working with a 555 and IR LED
- Stage 2 was...something. Probably adding in the monostable pulse circuit.
- Stage 3 was for range testing, I guess. We set up the receiver and transmitter on different breadboards.
- Stage 4 was testing with a LED bar graph and counter
- Stage 4.5 was testing with a 7-segment LED display instead of the bar graph
Currently, we're on Stage 4.5.
On the transmitter side, we have a LM556, with one half generating a short pulse when triggered, and the other half modulating the pulse to ~30kHz.
On the receiver side, we had the 30kHz detector, with its output leading to the "Down" input on a "74192 up/down decade counter" IC. The counter's BCD outputs connected to a "4511 BCD to 7-segment display decoder" IC. (alternatively, you can use a 7447 decoder IC if you use a common anode LED display versus a common cathode display)
We had some weird fading between numbers going on, probably because of electrical noise. We hope to eliminate that by using ICs with higher noise immunity. Something else we hope to add is another 555 timer circuit, connected to the "Up" input on the counter; we have yet to find a way to stop the separate 555 when the count has reached its maximum.
