Thanks to you both:

I had a go at banging it while making some bread yesterday, but, wouldja
know, it didn't drop out at all this time. Fraid it's like that: waits for
you to trust it and then ruins your whole dinner party...

I tend to agree that the poor contact somewhere is the probable cause. I
have not had one of these peculiar modern 'decoupled' knobs apart before -
i.e. where you turn it over a lot of 'bumps' but the dial does not feel as
if it's joined to anything. (Not to be confused with the kind as on our
washing machine, where the knob couples to the shaft when you push it in:
the oven ones do push in in order to fit flush when not in use, but they do
not push in to engage.) Presumably there are still some proper contacts in
there somewhere?

Cheers for the suggestions,

S


"John" wrote in message
...
Is the oven temperature dropping - or is it merely the thermostat
switching the input down due to it reaching its target temperature. Does
it cut back in after a while _ try opening the door to loose some heat to
see what happens.