Calculator-stopwatch converter circuit

Photocoupler

This circuit is suitable for any calculator with automatic constants that can be used as a stopwatch. The 555 timer is adjusted to the appropriate frequency and then connected to the calculator's battery and switch by pushing the switch.

Steel Pole

Steel pole

Steel poles are commonly used to carry several types of electric power lines, distribution lines and lighting system. Distribution lines carry power from local substations to customers. They generally carry voltages from 4.6 to 33kV for distances up to 30 miles, and include transformers to step the voltage down from the primary voltage to the lower secondary voltage used by the customer. A service drop carries this lower voltage to the customer's premises.

Steel Pole,Steel Street Light Poles,Galvanized Steel Pole,Steel Pole Tower

Yixing Steel Pole International Trading Co., Ltd , https://www.yx-steelpole.com