I bought half a dozen car key fob entry thingies from aliexpress
Each signal pin goes hi or lo depending on which button was pushed
Needs 3-5V at 5mA to be on, which is a bit high for batteries, but fine for a mains device
Yes, but that misses out the vital ingredient that I need, something with a numeric keypad that can sit out 'in public'. As I said I have loads of key fob type thingies which will operate the door, but I need a vaguely secure equivalent that you have to know a combination to operate.
Another possibility is to use an ibutton which you can have on a key fob and it just needs touching against an ibutton probe to activate although each i-button has its own unique code you could use software to scan only the unique codes for multiple ones if required.
As I keep saying we have lots of key-fob button devices that work fine. The numeric keypad is needed when you don't have any devices with you and/or (for example) if you want to tell someone else how to get into the garage when you're not there.
That’s when you get your mobile phone out and open it for them. ;-)
Tim
How do I know when they're there? I don't particularly want them to phone me when they arrive there at 3am, or for that matter when I arrive there at 3am and my phone battery is flat.
That’s when *they* get their mobile phone out and let you know they want you to open it. Phones are handy things.
Tim
Yes, when they work. Mobile coverage is decidedly poor by our house.
You can't win! :-)
"keypad programmable entry switch"
eventually led to this and its brothers:
Might be close to what you want. And it has a pinout, so some chance of checking if it might work, and at 3.38 pounds shipped...?
Thomas Prufer
Yes, thanks Thomas, that does indeed look as if it will do what I want and at that price is worth a try. It uses 12 volts which I have available nearby already.
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