Many years ago I roasted using a yellow pop-corn popper. I drilled a
small hole in the top and stuck a thermometer through a spacer so that
it just reached down to where the beans were. I also added an
additional switch so I could control the heating element and fan
separately! My experience back than was I could do a better job than
the roaster I purchased the fresh beans from and always having freshly
roasted beans was a treat. I have no recollection of the timing of my
roasts but I remember sitting next to it watching the color and the
temperature and turning the heating element on and off to control the
roast and then I'd just turn off the element at the end to cool the
beans. I always wanted to get a thermostat and make it automatic, now
that I program microcontrollers for a living so if I ever start
roasting again I'll probably make something to control the popper.
Ira