Thanks H Brunt & JS,
I have a Kenwood Electronic KM200 but I think the speed controller is the same as the a901. I bought the triac
BTA08-600B from Maplin for approx. £1.30. All the other components on the circuit board tested ok. Capacitors were not shorting, and there was not sign of swelling. The diodes tested OK. The triac is described as the speed controller in other forums. I de-soldered the part and soldered in the new one. It worked first time.
I would recommend using a de-soldering tool though. (http://www.maplin.co.uk/Module.aspx?ModuleNo=97040&C=Maplin&U=SearchTop&T=DESOLDER&doy=14m5).
I now have 2 working :) Kenwood chefs - as I bought an A901 and fixed a blown capacitor on that.
Ben
May 2007