Counter for coils, rpm, etc

[Trivo]

after finding how hard it was to count 12 coils of 40 turns with out loosing count i decided to find a better way.

i have found a counter module kit at dick smith (tandy electrical) that has three digits and expandable to 30. it can be activated by an magnetic reed switch, like in security systems, so you can put a magnet on a drill and every time it goes past the sensor it counts , or stick a magnet on a winder or on a prop blade or anything and it counts the turns or rpm so you can get accurate speeds of your prop by counting the turns per minute all i have to do now is build it

Trivo

[Norm]

 Here you go...a lot cheaper 8 digits...by

the time you get up to 99999999 you will

probably be thru winding coils for the day anyway

     I haven't updated my website(2nd link on this

posting. So I'll explain what I've done to my $.88

 counter.....

   I took it apart... on the printed circuit

where the button makes a path across the

gap,I taped (with a very small piece of transparent

tape) a short wire/s onto each side....drilled 2

very small holes at the bottom edge of the case,

right underneath the = button, brought the 2

wires thru, put a dab of hot glue.

   To be perfectly honest I didn't even think of

the reed switch until you mentioned it in your

posting here....

   Well that's it ...buy a reed switch from our

hosts and hook it on to these 2 wires and you're

in business!

http://www.fieldlines.com/story/2003/12/21/17710/268

 http://www2.suite224.net/~peppysue/Projects.html

    Oh....I almost forgot to mention this calculator

also comes with AA battery included that can be

replaced....some of the newer ones are even Dual Powered

(solar cell) and transparent case )...only drawback

they all have this automatic shut-off that shuts the thing

off along with the memory and the +1 pre-program that

you punched in.....Oh Well Whaat did you expect for

 a $buk!

                 Have Fun Trivo

                ( :>) Norm.