A high-frequency alternator is an electrical device used for radio communications. It yields high-frequency, periodically alternating current that can go as high as 100,000 Hz for the purpose of producing stable radio waves. The History of High-Frequency Alternators By the first decade of the 20th century, wireless telegraphy was already in place and was no …
The major types of satellite dishes include motor-driven dishes, multi-satellites, VSAT, and ad hoc satellites. Other types include DTH, SMATV, CABD, automatic tracking satellite dishes, and big ugly dishes. A motor-driven satellite dish is mounted on a pole which rotates around an axis to detect and receive various satellite signals in the sky. It is …
Standing Wave Ratio (SWR) meters are used to measure the standing wave ratio in a communications transmission line. The meter can display how much a transmission line and the load are mismatched (normally a radio antenna). It also determines how effective the impedance is of matching efforts. In CB and ham radio circles, the SWR …
Pulse position modulation is a signal modulation technique that allows computers to share data by measuring the time each data packet takes to reach the computer. It is often used in optical communication, such as fiber optics, in which there is little multi-pathway interference. Pulse position modulation exclusively transfers digital signals and cannot be used …
A CMOS (Complementary Metal-oxide Semiconductor) inverter is a device that produces logic functions and is the primary component of all integrated circuits. A CMOS inverter is a field-effect transistor that is composed of a metal gate that lies on top of an insulating layer of oxygen, which lies on top of a semiconductor. CMOS inverters …
dBm is the standard unit of measure for levels of power based on a one milliwatt (mW) reference signal. The dBm measurement is very similar to dB (decibel); however, dB is a relative measure of the power of an input signal while dBm is always an absolute value based on a single milliwatt. If there …
A photodetector is a device that imprints the image of an object or scene onto a material. Photodetectors are made in various ways and can be used for different purposes. Most photodetectors fall into the phototube, thermal detector, or camera category. These photodetectors are used for communication, navigation, and record keeping. Types of Photodetectors Phototube …
The crystal radio is a rudimentary radio receiver that can be made from a few easy-to-obtain and inexpensive parts. It is unique for this type of radio does not require a battery pack, has no moving parts, and can be built using ordinary household materials, yet it actually works. The only power it receives comes …
GPS stands for Global Positioning System. It refers to a system of satellites that constantly transmit a signal, and a GPS terminal that picks up those signals and calculates its position on Earth by measuring the distance between itself and two or more GPS satellites (by measuring the time it takes to receive the signals). …
A pulsation dampener is a device that can reduce or eliminate the intermittent gaps left in a pressurized system during the system’s discharge stroke. Pulsation dampeners are made for a variety of applications and can be used in virtually all pressurized devices to protect hardware, decrease maintenance costs, decrease down time, increase performance, and increase …