Thanks
cdev but I am looking for something much simpler and much cheaper ... and by the looks of it very non existing
I have a stock of very simple access control circuits and am looking for any possibility of putting them to some use. I know I can buy complete systems but, again, I am looking for a very low cost keypad which would allow me to put the stock I have to some use.
My experience is that outdoor weather is very harsh and soon the sun, rain, dust, etc, take their toll.
I am beginning to get involved more in things mechanical and have thought maybe I could build some keypads by using some weatherproof push button switches but even those are not cheap or easy to find.
Maybe I could use regular push-button switches enclosed hermetically and with a membrane which allowed pushing them. In other words, the outside, visible button just pushes a membrane and behind is the real switch.
Another possibility is to use reed switches but, again, not simple.
Anything made of plastic should probably be protected from the elements by a box with a cover which is only opened when the user is going to use the keys.
Part of the problem is finding switches with numbered keycaps.
It just seems strange to me that this is not something easily commercially available because I think there would have been a need.
I guess I could use keypads recycled from old phones but I don't think they would stand well to the weather.
As I dedicate more time to machining I might attempt making something myself but engraving the key caps remains a problem. Probably not an efficient use of my time either. Oh well. The stock of circuits I have will probably end up in the junk.