Search results
Results from the WOW.Com Content Network
A tuned radio frequency receiver (or TRF receiver) is a type of radio receiver that is composed of one or more tuned radio frequency (RF) amplifier stages followed by a detector (demodulator) circuit to extract the audio signal and usually an audio frequency amplifier. This type of receiver was popular in the 1920s.
Today's radios are usually uneconomical to repair because mass production and technological improvements in numerous areas have made them so inexpensive to buy, while the cost of human labor and workshop overheads have increased greatly in comparison. Typical insides of an antique radio, showing the vacuum tubes.
English: Block diagram of a tuned radio frequency (TRF) receiver, the simplest type of amplifying radio receiver circuit. It consists of one or more tuned RF amplifiers, each consisting of a tuned circuit which functioned as a bandpass filter followed by a radio frequency (RF) amplifier; a detector (demodulator) to extract the audio waveform from the radio carrier wave; followed by an audio ...
English: Block diagram of a tuned radio frequency (TRF) receiver, a type of radio receiver circuit invented in 1916 by Ernst Alexanderson and widely used in the vacuum tube receivers of the 1920s.
A prominent Beaver Falls building is on the market as owners of a historic antique shop go virtual.
"Today, we're going to give it an insurance valuation of $150,000 to $200,000," said appraiser Allan Katz on "Antiques Roadshow." "That's extraordinary," said the tooth's owner. Ain't that the tooth!
The Neutrodyne radio receiver, invented in 1922 by Louis Hazeltine, was a particular type of tuned radio frequency (TRF) receiver, in which the instability-causing inter-electrode capacitance of the triode RF tubes is cancelled out or "neutralized" [1] [2] to prevent parasitic oscillations which caused "squealing" or "howling" noises in the speakers of early radio sets.
The Neutrodyne receiver, invented in 1922 by Louis Hazeltine, [133] [134] was a TRF receiver with a "neutralizing" circuit added to each radio amplification stage to cancel the feedback to prevent the oscillations which caused the annoying whistles in the TRF.