In which decade was the ARRL founded?

The first laser was a solid state laser. Solid state refers to any solid material like a glass rod. Diode lasers are very common because they are used to read compact disks and digital video disks in computers, CD players, and DVD players. Before diode lasers, the most common type of laser may have been the helium-neon laser, in which the active medium is a combination of the two gasses helium and neon.

RF is radio frequency. IF is intermediate frequency used inside the TV for processing. AF is audio frequency. SAP is second audio program which may have another language or other soundtrack as an option to the main soundtrack.

JVC (Japan Victor Corporation) and Matsushita (Panasonic) developed the VHS format to compete with Sony which developed the Beta format as the first home video cassette recorder. VHS originally stood for Vertical Helical Scan, but now means Video Home System.

PAL and SECAM are standards used in other countries. RGB stands for red, green, and blue - the colors of light used to create an image in a color tv set and is often used as a format name for computer monitors.

This voltage often remains in storage even if the set is unplugged. Although the voltage is very high it has very low power but it can be dangerous because your body jumps if brought in contact.

The word "laser" is actually an acronym for light amplification by stimulated emission of radiation. Atoms or molecules of the active medium that have been excited to a higher energy level are stimulated by a passing photon to relax to a lower energy level and emit a photon that is indistinguishable from the passing photon, thereby increasing the number of photons like the incident one.