Sunday, April 19, 2015

RCA - Radio Corporation of America

The Professor, Talking Machine, Wireless Becomes Radio, Color Television, Nipper and Chipper and More RCA History at....

The Wayback Machine snapshot of RCA History.

Guglielmo Marconi, an Italian electrical engineer, transmitted the first wireless signal in 1895. By the turn of the century he had formed telegraph companies in England and opened the first wireless office in New York City. In 1901, Marconi telegraphed the letter "S" across the Atlantic Ocean. The U.S. Navy was so impressed that it replaced a flock of carrier pigeons with the "wireless" for ship-to-shore communications.

Two years after inventing the phonograph, Edison brought the world the incandescent light bulb. Thirteen years later, his start-up electric company would merge with the Thomson-Houston Electric Company and be renamed General Electric.

RCA - Radio Corporation of America

In 1929, RCA purchased the Victor Talking Machine Company, then the world's largest manufacturer of phonographs (including the famous "Victrola") and phonograph records. This included a majority ownership of the Victor Company of Japan, or JVC. The new subsidiary then became RCA-Victor. With Victor, RCA acquired New World rights to the Nipper trademark. This Trademark is also the trademark for the British music & entertainment company HMV who now display nipper in silhouette.

In the early 1920s, David Sarnoff publicly speculated on the possibility of "every farmhouse equipped not only with a sound-receiving device but with a screen that would mirror the sights of life." The idea of television was not new, and mechanical systems had demonstrated crude pictures. But it was Sarnoff's historic meeting with engineer Vladimir Zworykin that set the stage for RCA's success at electronic television transmission and reception.

Wikipedia - RCA - Radio Corporation of America

An RCA connector, sometimes called a phono connector or cinch connector, is a type of electrical connector commonly used to carry audio and video signals. The name "RCA" derives from the Radio Corporation of America, which introduced the design by the early 1940s to allow mono phonograph players to be connected to amplifiers.

RCA Connector at Wikipedia

Friday, April 17, 2015

Mains Voltage and Power Circuits

Mains Power means the 230 V AC 50 Hz or 110 V AC 60 Hz in some countries, The lower power line like 5A is used for small lamps and fans. The higher power line 15A is used to drive the High Power Electrical Appliances like Heaters and Motors. This is a single phase supply.

Mains Voltage and Power Circuits

Single phase Supply in layman language means a Live, a Neutral and an optional earth. The earthing is a must in every building along with lightning protection. The Neutral is a close to earth potential, The live can give a shock to a man who is in contact with earth at some part of the human body. So great care has to be taken. This live wire or point can be easily checked by a quality standards approved Neon Tester.

Voltmeter and Ammeter

Three phase supply - there are three Live wires, used in factorys and apartments to power bigger loads and Motors. A 3 phase AC motor is very efficient and economical and most machines like Drills and Lathes are powered by AC Motors. 3 phase supply becomes essential for industry.

The voltage is transmitted and supplied to houses at a high level in comparison to low level of batteries. This High Voltage is not safe but Inevitable, as transmitting at lower voltage means greater current carrying requirements of wires and connectors. That leads to more copper or aluminum usage, more wastage of power due to I2R.

Earthing has to be good, use a Earth Leakage Trip Device. If earth wire gets snapped outside and some appliance is leaking, the metal clad appliances may give shock. Even if no appliance is leaking, the current thru y-capacitors of EMI Filters in Electronic Gadgets like computers are enough to make your Neon tester glow.

The Circuits related to Mains Power

Wednesday, April 08, 2015

The Timeless Performer - 555 IC Chip

The Incredible 555 : Here are some 555 circuits, The most versatile and simple chip of all time !

Some of my 555 Circuits are at my blog - 555-Circuits - delabs Schematics

The best part of the 555 is that it has an voltage detection. It has a Versatile Logic which is defined by voltage comparators. The ability to loop it like an opamp for feedback makes it the first "Programmable" Mixed Chip. In short it make an ideal building block.

555 The most Incredible Chip - At my Learning-Teaching Blog Solderman Basics.

Signetics made the 555, This is one IC that is like a E-LEGO, this along with Op-Amps and other components can make many interesting projects. On some pins like Control Voltage it responds to analog signals and on Reset and Output the signals are Digital like. The 7555 a CMOS version consumes lower power and oscillates at higher frequencies.

555 Timer Circuits at delabs

555 Timer based Circuits