Electronic Projects, forums and more.

Go Back   Electronic Circuits Projects Diagrams Free > Electronics Forums > General Electronics Chat


General Electronics Chat This forum is for general chat about electronics, eg: Dont know what a part does? Dont know how to read a circuit? Want to get an opinion?

Reply
 
LinkBack Thread Tools Display Modes
Old 16th August 2008, 05:08 AM   (permalink)
Default Photo optic event counter needed

Hello,

I'm looking for a counter that will count up, only one count each time a hand goes into a box and touches a meteorite exhibit at a science center.

A counter is needed that will keep its count information even if power has been taken away, yes non-volatile memory. I want to keep track how many times a meteorite has been touch by the public, there is 1.2 million vistors each year. Maybe only 200,000 per year will trigger the counter or more.

If you don't know where I can get something like this. I hope someone will know who will, I really want to make this happen

Please help me in this matter.


Sincerely,
Tim

Last edited by easytim; 16th August 2008 at 11:20 PM.
easytim is offline  
Old 16th August 2008, 05:19 AM   (permalink)
Smile

A 99¢ solar powered calculator fed by a long life battery instead of relying on its solar cells will keep the counting alive for very, very long time.

Introducing the value 1 (one) on memory, if the hand-in-the-box sensing circuit triggers the calculator M+ key, you have a digital counter.

Miguel
__________________
Abolish the deciBel !
Externet is offline  
Old 16th August 2008, 05:44 AM   (permalink)
Angry Warning!

Quote:
Originally Posted by Externet View Post
A 99¢ solar powered calculator fed by a long life battery instead of relying on its solar cells will keep the counting alive for very, very long time.

Introducing the value 1 (one) on memory, if the hand-in-the-box sensing circuit triggers the calculator M+ key, you have a digital counter.

Miguel
The $1.00 calculators I have found lately have NO solar cell, just a picture of one!
But they do have a battery; aren't those Chinese SOB's clever.
Rolf is offline  
Old 16th August 2008, 10:16 PM   (permalink)
Default

Quote:
Originally Posted by easytim View Post
A counter is needed that will keep its count information even if power has been taken away.
So you need a non-volatile memory.

How accurately do you need to read the count? Better than 1%? 5%?
Willbe is offline  
Old 16th August 2008, 10:19 PM   (permalink)
Default

Quote:
Originally Posted by Rolf View Post
The $1.00 calculators I have found lately have NO solar cell, just a picture of one!
But they do have a battery; aren't those Chinese SOB's clever.
A guy at work bought a portable USB charger (to charge USB devices from a battery anywere) that had a few unwired coils and relay things inside to make it look complicated and a piece of rusted metal to add weight.
__________________
NO, that picture isn't me so don't bother asking if we can be friends.

Last edited by dknguyen; 16th August 2008 at 10:20 PM.
dknguyen is offline  
Old 16th August 2008, 10:32 PM   (permalink)
Default

Quote:
Originally Posted by Willbe View Post
So you need a non-volatile memory.

How accurately do you need to read the count? Better than 1%? 5%?
What accuracy do you expect adding 1 + 1 in a calculator?

A calculator is not an estimator.
__________________
Proper Planning Prevents Piss Poor Performance
Boncuk is offline  
Old 16th August 2008, 11:17 PM   (permalink)
Default

Quote:
Originally Posted by Boncuk View Post
What accuracy do you expect adding 1 + 1 in a calculator?

A calculator is not an estimator.

It does not need to be perfect, it would be a cool idea after 300,000 people have touched this counter display be seen by those who come to touch it.

A big read out, digital display for all to see. Maybe a big sign that says you are the 300,000 person to touch this, next person, you are the 300,001 person to touch this.
easytim is offline  
Old 16th August 2008, 11:17 PM   (permalink)
Default

Quote:
Originally Posted by Willbe View Post
So you need a non-volatile memory.

How accurately do you need to read the count? Better than 1%? 5%?

It does not need to be perfect, it would be a cool idea after 300,000 people have touched this counter display be seen by those who come to touch it.

A big read out, digital display for all to see. Maybe a big sign that says you are the 300,000 person to touch this, next person, you are the 300,001 person to touch this

Last edited by easytim; 17th August 2008 at 12:55 AM.
easytim is offline  
Old 16th August 2008, 11:31 PM   (permalink)
Default

Quote:
Originally Posted by easytim View Post
It does not need to be perfect, it would be a cool idea after 300,000 people have touched this counter display be seen by those who come to touch it.

A big read out, digital display for all to see. Maybe a big sign that says you are the 300,000 person to touch this, next person, you are the 300,001 person to touch this
OK.
Non-volatile memory.
Six or seven digit display.
Each digit resolvable (no rounding)
Photocell sensing.

This runs off the wall outlet or batteries?
Indoor environment?
High ambient lighting?
Any adverse environmental stuff - moisture, vibration, etc.?
Willbe is offline  
Old 17th August 2008, 12:43 AM   (permalink)
Default

Quote:
Originally Posted by Willbe View Post
OK.
Non-volatile memory.
Six or seven digit display.
Each digit resolvable (no rounding)
Photocell sensing.

.



This runs off the wall outlet or batteries?
Indoor environment?
High ambient lighting?
Any adverse environmental stuff - moisture, vibration, etc.?


.
It needs to run on 110vac wired to a junction box with a battery back-up.

This counter would work http://www.electronickits.com:80/kit...lec/ck1612.htm with 12vdc but I need a photocell circuit to trigger counting or a touch alarm circuit.

I can do a 12vdc 7 AH lead acid battery with a battery charger to keep battery charged, they use these in home alarms.

That lead acid battery and charger combo I think would work well to power it. Unit will be used in an Indoor environment, not a brightly lighted room, no moisture or vibration.

Maybe I can use this 12vdc touch alarm circuit to trigger counting http://www.uoguelph.ca/~antoon/circ/alarm2.htm

The idea here is when you finger touches the hole where the Mars Meteorite is (around that hole is a small metal ring that triggers a count) it counts up one


.

Last edited by easytim; 17th August 2008 at 01:07 AM.
easytim is offline  
Old 17th August 2008, 01:05 AM   (permalink)
Default

These chinese are something ! Adding scrap metal, useless parts, faking a solar cell...

Seen 11 inch x 8 inch very large digits display/large buttons calculators at the 99 cent store too, perhaps with some luck you can find those ; or ordering on the net.

Like this----> http://www.amazon.com/Digit-Display-.../dp/B000WSL87E

Miguel
__________________
Abolish the deciBel !

Last edited by Externet; 17th August 2008 at 01:08 AM.
Externet is offline  
Old 17th August 2008, 04:30 AM   (permalink)
Default

Hi easytim,

did you notice that the counter you mentioned has only four digits for display? To count up to 999,999 six digits are required.

I suggest making an own design cascading six CD40110 decimal counters. To clock the counter you might use an IR-barrier arranged the way that only hands touching the metorite can trigger the counter.

For display you might use Kingbright 7-segment LEDs of 100mm height. (package height 122mm)

Hans

Last edited by Boncuk; 17th August 2008 at 04:35 AM.
Boncuk is offline  
Old 17th August 2008, 06:06 AM   (permalink)
Default

Quote:
Originally Posted by Boncuk View Post
Hi easytim,

did you notice that the counter you mentioned has only four digits for display? To count up to 999,999 six digits are required.

I suggest making an own design cascading six CD40110 decimal counters. To clock the counter you might use an IR-barrier arranged the way that only hands touching the metorite can trigger the counter.

For display you might use Kingbright 7-segment LEDs of 100mm height. (package height 122mm)

Hans


.



Please read more, you can use two, then it will give it 8 digits. Thats some great ideas you have given me THANKS






.

Last edited by easytim; 17th August 2008 at 06:10 AM.
easytim is offline  
Old 17th August 2008, 10:09 AM   (permalink)
Default

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]!"
__________________

Russ Martin

"Easy to use is easy to say."
RussMartin is offline  
Old 17th August 2008, 10:15 AM   (permalink)
Default

Hi easytim,

I've already designed a schematic and layout for the six-digit-counter. Is the 4-digit-counter built the way that two of them fit together to make them look like one display?

I also have a circuit and PCB-layout for an IR-barrier to be used for object recognition in a can crusher.

This is what the 100mm display looks like. Power supply connector and RESET-button are on the right hand side. The counter & decoder ICs are underneath the display.

Regards

Hans
Attached Images
File Type: jpg counter.jpg (19.5 KB, 9 views)
__________________
Proper Planning Prevents Piss Poor Performance
Boncuk is offline  
Reply

Bookmarks

Thread Tools
Display Modes



Similar Threads
Title Starter Forum Replies Latest
[b]HELP! how to build an event counter... [/b] poch Electronic Projects Design/Ideas/Reviews 10 27th May 2008 05:01 AM
What is Photo Diode & Photo Transistor? Suraj143 General Electronics Chat 9 26th October 2007 11:11 AM
event control timer basb1 Electronic Projects Design/Ideas/Reviews 1 19th March 2006 07:57 PM
Fibre optic talkset tester homebuild circuits needed SecTec Electronic Projects Design/Ideas/Reviews 0 10th January 2006 07:43 PM
Event Counter Revisited... captainkirksdog Electronic Projects Design/Ideas/Reviews 1 30th December 2003 02:44 PM



All times are GMT. The time now is 02:13 PM.


Electronic Circuits  |  Learning Electronics
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.

eXTReMe Tracker