Door bell timer using 555 IC?

[Yorkie]

I think from what you say Keith, It's back to the drawing board! I'll perhaps redesign the PCB layout for a circuit to incorporate a transistor to drive the relay and etch a new PCB.

I've cobbled together such a circuit based on bits from internet offerings, which I've attached. Don't know how that looks! Any suggestions as to a suitable commonplace NPN transistor to drive the relay please? As I've noted on the drawing, the relay coil is 280 Ohms,. so at 12 V would pass 43 mA or thereabouts for maybe 5 secs or so when the doorbell button is pressed. (I'll most likely make the 22k resistor on pin 6/7 a pre-set to enable the 'on' time to be varied).

As to NVCF, yes, I'll be there with my wife, Jennifer, and I know that Gary will be there so I'll look out for you when 'doing the rounds'. I usually hover around the bring and buy at 12 noonish for an informal chat with any forum members should the mood take them, but it's  invariably a bit hit and miss because everyone seems to gets a bit engrossed in their hunt for 'unobtanium'  

I'll have my little 'Yorkie' badge on, and though the years are taking their toll, I still have a passing resemblance to my avatar pic, taken six years ago on my 70th birthday!

Hope to see a few forum members to pass the time of day with.