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code lock keypad questions....

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eyevancsu

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http://www.electronicsforu.com/efylinux/circuit/jan2000/jancir2.htm

the above link is a project im about to begin just for the fun of it, not intended for security purposes. I have all of the parts except for the IC's which i havent bought, havent found many. Could there be any replacements for these two, as in a part that combines both or just simply on that can adequately replace these? I am not looking for project involving programing chips, (does this circuit have to be programmed with a programmer???). Also, what type of keypad must be used for this, will any pretty much do as long as it has 9 keys?

any help will be greatly appreciated.

regards,

ivan
 

bogdanfirst

New Member
look, i think that circuit is too colmplicated for what it does....i have a circuit for a 7 digit code swith just one IC and it works fine, ...wel i still have to build the pad with the keys, but i have tested it and it works....
it uses a simple 4022 8 stage counter, you can replace it with a 4017 this way you will have a 9 digit code.....
if you are interested i can scan the schematic.....
 

Chippie

Member
To answer the question on the keypad, not any old pad will do!!! Most keypads are arrange din a matrix formation with rows/column addressing.

The kp in the cct is showing one side of each of thes witches as being commoned up.....therefore you will need to assemble your own pk based on that cct.....
 

eyevancsu

New Member
bogdanfirst; i checked the national.com website and saw that the 4022 ic was a discontinued part as well as the 4017. if anyone has any available or knows where i can find some please dont hesitate to post it/them here. I would appreciate it if you could post a copy of the schematic bogdan.

Thanks alot!!!!!
............................Ivan
 

bogdanfirst

New Member
yes, but there are other companies that still produce them....i have no troucle finding them....
i have an idea about the pad....take an old calculator, or but a cheap one and try to brake the copper links on the pcb and then make some holes and reconnect the buttons with wires on the other side
or another one....if you can make your pcb, then no problem will be at all...there are lots of types of buttons you can use...even ones from an old keyboard....also have the numbers on them :D
 

Phasor

Member
4107 and 4022 are definitely not discontinued! You don't have to use National - any brand will do!
 
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