Hello everyone,
I ran across this site about a week ago when I was searching for long range IR emitter/receiver circuits. I am senior at Penn State University and we are doing a senior project where a portion of it requires an IR emission and reception. By long range I mean, we need to get at least 20 feet. I have been working and troubleshooting for some time now on this and can't seem to get it.
I am using a LM555CN chip set to output a 38kHz signal with a 50% duty cycle. I know this is the signal being output b/c I can see/measure it on the o-scope. The circuit can be seen in my attachment.
But here's where I run into problems. I am using left over components from a previous senior design project where another team has completed a similar task.
-I don't know the specs on the IR LEDS
-I don't know the specs on the photoelectric receivers. But I do have their old setup (photoelectric receivers, resistors, and capacitors.)
-Their design report says they used a 38kHz signal with 50% duty cycle
-The receivers have the following marking:
19 235
V7000
So can anyone point me in the right direction where to go from here? I've hooked up their old unit and have a logic high, but when I place it in front of the IR LEDS, nothing happens.
Please advise (sorry if this seems like a scrambled message)