Search results
Results from the WOW.Com Content Network
Projects in Amateur Radio and Short Wave Listening (Newnes 1981) Electronic timer projects (Babani 1981) Beginner's guide to amateur radio with John Earl (Newnes 1982) Integrated circuits for beginners (published by Babani 1982 posthumously)
The term radio receiver is understood in this article to mean any device which is intended to receive a radio signal in order to generate useful information from the signal, most notably a recreation of the so-called baseband signal (such as audio) which modulated the radio signal at the time of transmission in a communications or broadcast system.
The ZN414 is a low cost, single-chip AM radio integrated circuit. Launched in 1972, the part was designed and supplied by Ferranti, but was second sourced from GEC-Plessey. The ZN414 was popular amongst hobbyists, as a fully working AM radio could be made with just a few external components, a crystal earpiece and a 1.5 V cell.
It is accomplished by a circuit called an envelope detector (see circuit), consisting of a diode (D) with a bypass capacitor (C) across its output. See graphs. The amplitude modulated radio signal from the tuned circuit is shown at (A). The rapid oscillations are the radio frequency carrier wave.
A radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna. Radio waves are electromagnetic waves with frequencies between about 30 Hz and 300 GHz. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the ...
Radio-frequency (RF) engineering is a subset of electrical engineering involving the application of transmission line, waveguide, antenna, radar, and electromagnetic field principles to the design and application of devices that produce or use signals within the radio band, the frequency range of about 20 kHz up to 300 GHz.
The crystal radio receiver is the simplest kind of radio receiver or tuner, and was the basis for the first commercially successful type of radio product design. Inexpensive and reliable, it was sold in millions of units and became popular in kits used by hobbyists, and was a major factor in the popularity of radio broadcasting around 1920.
This circuit can be programmed for step up, step down, positive, negative, voltage and current regulation. Robert Frostholm 51/2 February 1980 Not just another digital clock [2] 5 + 1 ⁄ 2-inch high single-digit LED readout makes this clock unique. John D. Warobiew 51/2 February 1980 Automotive burglar alarm [3] Build it for less than $20.