The Tappan Deluxe has two different versions of clocks.
The first is the Telechron Clock, generally found on non-CP stoves. It functions as a clock and has a timer that buzzes. Pretty simple.
There appears to be a few different versions of this clock. Mine has large red numbers on a face plate (and does not say "telechron" on it), but I have seen older stoves with smaller numbers with intervals for timing. If anyone has more info. on this, I'd be interested in hearing it.
The second style is the Time Control Clock. This is the clock style found on CP stoves. It has three knobs on the right side (black, red and metallic or white). It functions as a clock, but it also works as a timer to turn the oven on and off. Tappan advertised that you could set this clock with your full meal int he oven and then leave the house. I don't think I'd be brave enough to try that, but a handy feature nonetheless.
P.S. I realized that I had the blog comments accidentally set so you had to register in order to comment. Oops. That has been fixed. If you tried to comment before and it was a huge hassle, I apologize.