Hi John and others,

> There appears to be some kind of data bus to communicate between a central 
> control unit and sensors 

It's CANBUS. It's used as a communication system around vehicles and controls 
all sorts of things as well as bringing data back from sensors. When Robin 
G8DQX and I were over with you, we got a chirruping on the LF Rx when the doors 
were opened or closed. When we were doing nothing with the controls, with the 
ignition off, we didn't notice any interference.

73,
Chris G4OKW

-----------------------
Dr Chris Trayner
School of Electronic & Electrical Engineering,
The University of Leeds,
Leeds LS2 9JT, United Kingdom
Tel: +44 113 34 32053
Fax: +44 113 34 32032