Photo optic event counter needed - Page 2 - Electronic Circuits Projects Diagrams Free

Willbe · 17th August 2008, 01:37 PM

If the interval between the first person touching the thing for the first time and the second person touching the thing for the first time
is 10 seconds or so,
you might need a retriggerable one-shot to lock out the counter for this interval.

Mike, K8LH · 17th August 2008, 04:48 PM

Quote:

Originally Posted by Boncuk

Hi easytim,

I've already designed a schematic and layout for the six-digit-counter.......

Who hasn't (grin)...

easytim · 17th August 2008, 05:36 PM

Quote:

Originally Posted by RussMartin

Just curious:

What/where in St. Louis is the place where this would be? I remember visiting a really fine children's science museum there about 25 years ago.

Obviously, there are many ways to accomplish what you are asking about, beginning with cascaded decade counters and going up all the way to--gasp!

--a microprocessor.

I think optical beam interruption (visible light or infrared) may be a better choice than a touch sensor.

You might consider a little bit of delay time (a very few seconds) before the sensor (whichever you use) is able to be triggered again.

There will always be people who will touch the thing repeatedly just to watch the numbers change. Since your sensor can't tell people apart, perhaps the sign should read "This meteorite has been touched [numeric display] times since [date installed]!"

At the St. Louis Plantaruim.

I was thinking of putting a 15 second delay on counter. So it only counts up once every 15 seconds, touch it once then you need to wait 15 seconds for it to count up one more time.
I know now it will be triggered more than once by one person , but it still counts for how many times it has been touched. It still counts for a touch, its not really how many people touched it, but how many times it has been touched that will be counted. Your right a sign that says how many times it has been touched, not how many people

.

.

Boncuk · 18th August 2008, 01:45 AM

Quote:

Originally Posted by Mike, K8LH

Who hasn't (grin)...

Have you?

(100mm LEDs)?

easytim · 18th August 2008, 01:55 AM

Quote:

Originally Posted by Boncuk

Have you?

(100mm LEDs)?

No I do not have 100 mm Leds, I'm looking for those counters that have a 3 volt battery to retain memory built in

Mike, K8LH · 18th August 2008, 04:34 AM

Sounds like a 'fun' project.

If you're considering the 100mm (4 inch) displays, they usually require a higher voltage so source drivers are different. The circuit below should work. Full brightness with PWM brightness control. Add power brick, regulators, and switches if necessary. Battery backup?

If this is a "one off" project you might be able to draft one of us PIC guys to help you with the program and to burn a chip for you.

Regards, Mike

easytim · 18th August 2008, 11:19 AM

I know this may not be a big enough display, but it could fit my needs better, I like the idea of a 3volt battery to retain memory for 6 years http://www.redlion.net/Products/Digi...ing/CUB4L.html

.
I think a copper washer around the hole where a persons finger goes to touch it can be used as the touch plate http://www.uoguelph.ca/~antoon/circ/touch1.html

I'm thinking of adding a capacitor across a small relay to hold the replay in for 15 seconds or more so it can only be triggered once in 15 seconds

Thanks for your Mike and everyone else who has posted ------------- A BIG THANKS

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17th August 2008, 01:37 PM	(permalink)
Willbe	If the interval between the first person touching the thing for the first time and the second person touching the thing for the first time is 10 seconds or so, you might need a retriggerable one-shot to lock out the counter for this interval.

18th August 2008, 11:19 AM	(permalink)
easytim	I know this may not be a big enough display, but it could fit my needs better, I like the idea of a 3volt battery to retain memory for 6 years http://www.redlion.net/Products/Digi...ing/CUB4L.html . I think a copper washer around the hole where a persons finger goes to touch it can be used as the touch plate http://www.uoguelph.ca/~antoon/circ/touch1.html I'm thinking of adding a capacitor across a small relay to hold the replay in for 15 seconds or more so it can only be triggered once in 15 seconds Thanks for your Mike and everyone else who has posted ------------- A BIG THANKS Last edited by easytim; 18th August 2008 at 12:58 PM.