"Andy Cap" wrote in message
...
On Tue, 15 Apr 2008 18:38:04 +0100, "Mr Sandman"
wrote:

the problem is now that if
someone opens the back door with a fob, the front door also unlocks! and
vice versa. I was thinking about using diodes to try to get round this
problem. I'm not sure if I have explained the set up very well..so ask
away
if you have any questions!

If it's a DC sensing circuit, then yes a diode in one leg of each branch
will do
the trick. If it doesn't work at all one way, reverse it.

If it's AC sensing it wouldn't make any difference. I'd guess and you'd
have to
go the relay route.

Be careful though, it's might be mains voltage !!!! Get something
sturdy, 1A
rated at 400v. They only cost pence anyway.

Andy


Hi Andy. thanks for the useful response! Its just 12 Volts DC, so I can dig
a couple of diodes out of an old PCB somewhere I'm sure. Where do you
suggest I put them? one on each of the wires to the power supplies? I'm
sure I can have a play, cant do any harm. I suppose there must be some
electron transfer in some direction across the sensing terminals, I just
need to find out which is positive I imagine?

cheers!

Steve