Isn't it great how much "better" appliances are now that they added electronic controls? Our house came with a JennAire glass cooktop. We'd trade it in a heartbeat for a good old-fashioned, rheostat-controlled, wire coil cooktop that would last for decades and do a better job of cooking stuff.
rheostat-controlled, wire coil cooktop that would last for decades and do a better job of cooking stuff.
Contrary to popular belief, the control knobs on older coil cooktops are not rheostats.
They are a rather clever device commonly called and "infinite switch" that uses a bimetallic strip. As current flows through it it heats up, bending the strip which then breaks the contact. As it cools off, it unbends and restores the current flow. In this way it continuously cycles power on and off to the heating coil. Adjusting the knob varies the spring pressure on the strip, which changes the duty cycle (on time) of the on-off cycle. All this without any electronics at all!