Hello again. Since this is my second instructables, I think that be a little better!
The circuit I describe here, and a simple counter of objects, which contain up to 99 objects (most forward and teach the ability to extend counting).
The circuit is based on three blocks, and the sensor, circuit and display.
Lock the pictures:

Step 1: Take the Parts

The circuit uses few parts, all at low cost. For this project you will need the following pieces:

-1 Infra-red LED
-1 Photo-transistor
-1 Double red LED display (common katode)
-2 IC CD4026
-1 10K resistor
-2 1k resistor

So. In the next pictures you have the tracks, of the up side and down side (because you need use de double-face PCB).
I test my project in one protoboard.
And that. Good luck in your assembly and until the next
<p>I need to install 10 counters, but I need a total counter to get the final score from the 10 counters! It that possible?</p>
Yes, it is. Just put the sensors in parallel
<p>I need to install 10 counters, but I need a total counter to get the final score from the 10 counters! It that possible?</p>
<p>Hi, </p><p>Can this counter 1+1 =2: 2+1= 3...........</p><p>Can make this counter 2+2=4 ; 4+2=6 ...........</p><p>Can make this counter 3+3=6; 6+3=9 ...........</p><p>Can make this counter 4+4=8; 8+4=12..............</p><p>What thing I need to replace to make work like that?</p><p>I will need to buy 10 units</p>
So, does this use a broken infra-red beam to count objects, like those moving on a conveyor belt? Can the input be changed for a manually operated push button? Could there be a second push button that would reduce the count, too? I was a secret shopper at a movie theater. I had to count the patrons. They would come in, but then leave after a few minutes to get popcorn, etc. I tried to do the count in my head, but it meant adding and subtracting simultaneously.
Yes, It's possible to add a push button, just put it instead of Photo-Transistor, but, to decrease the number, this IC doesn't support this feature. I may do a circuit, but only with microcontrollers. Ok?
Thank you. I no longer have the responsibility of being a secret shopper in a movie theater.