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Electric gates are recommended to be used in combination with other security features to install a full security system. A few of these features are closed circuits with security cameras, additional gates in conjunction with the main gate, electronic keycards and keypads, security guards. [8]
The electric overhead garage door opener was invented by C.G. Johnson in 1926 in Hartford City, Indiana. [1] Electric Garage Door openers did not become popular until Era Meter Company of Chicago offered one after World War II where the overhead garage door could be opened via a key pad located on a post at the end of the driveway or a switch inside the garage.
Remote controls send a digital code word to the receiver. If the receiver determines the codeword is acceptable, then the receiver will actuate the relay, unlock the door, or open the barrier. Simple remote control systems use a fixed code word; the code word that opens the gate today will also open the gate tomorrow.
A quick demonstration of an electronic door lock. An electronic lock (or electric lock) is a locking device which operates by means of electric current. Electric locks are sometimes stand-alone with an electronic control assembly mounted directly to the lock.
A telephone keypad is a keypad installed on a push-button telephone or similar telecommunication device for dialing a telephone number. It was standardized when the dual-tone multi-frequency signaling (DTMF) system was developed in the Bell System in the United States in the 1960s – this replaced rotary dialing , that had been developed for ...
Apollo Command Module primary guidance system components Apollo Lunar Module primary guidance system components Apollo Inertial Measurement Unit. The Apollo primary guidance, navigation, and control system (PGNCS, pronounced pings) was a self-contained inertial guidance system that allowed Apollo spacecraft to carry out their missions when communications with Earth were interrupted, either as ...
Apollo 13 had drawn heavily on its entry batteries in the first hours after the explosion, and while this new battery could not power the CM for more than 5–10 hours it would buy time in the event of a temporary loss of all three fuel cells. Such an event had occurred when Apollo 12 was struck twice by lightning during launch.
The Apollo/Saturn V Center, located 6 miles (9.7 km) north inside NASA's gates, is a large museum built around its centerpiece exhibit, a restored Saturn V launch vehicle, and features other space related exhibits, including an Apollo capsule. Two theaters allow the visitor to relive parts of the Apollo program.