where should i press to start it??

Question

http://www.electronics-lab.com/projects/oscillators_timers/014/index.html

i use to construct this circuit. however when the supply connected i realize that there are no start button to make the stopwatch start counting up. i actually tought that when the supply is given, the stopwatch will start counting. however it is not. please anybody help me...

Answer 1

I've only made a cursory study of the circuit design, but have found that the ground connection is missing on the schematic for all but one of the microcircuits. Pin 8 (Vss) on each device must be connected to ground. When power is applied, the oscillator should be running and the circuit should be counting down.

Data sheets for each of the microcircuits is available on the link below. Do a search by the part number, omitting the leading and trailing letters, for example, "4060".