[af024]

Thank you for your further comments. Yes the worm gear is available (well the standard non-stop motion type seems to be), but boy you need patience to fit one and ensure that everything is properly synchronised up again.

Between pins 3 and 4 of the module (everything disconnected from it), using a standard analogue multimeter, I'm 'seeing' circa 650 ohm (one direction).

I also observe (when everything is connected) 0.7 Vd.c. at pin 3 relative to pin 4 when the motor is running and 0.2 Vd.c. when the motor switch is turned to off. This doesn't agree with the voltages marked on the circuit as it states 14Vd.c. 'at projection'.