Search results
Results From The WOW.Com Content Network
A 5-tube superheterodyne receiver manufactured by Toshiba circa 1955 Superheterodyne transistor radio circuit circa 1975. A superheterodyne receiver, often shortened to superhet, is a type of radio receiver that uses frequency mixing to convert a received signal to a fixed intermediate frequency (IF) which can be more conveniently processed than the original carrier frequency.
In double-conversion superheterodyne receivers, a first intermediate frequency of 10.7 MHz is often used, followed by a second intermediate frequency of 470 kHz (or 700 kHz with DYNAS [15]). There are triple conversion designs used in police scanner receivers, high-end communications receivers, and many point-to-point microwave systems.
Block diagram of a dual-conversion superheterodyne receiver. To achieve both good image rejection and selectivity, many modern superhet receivers use two intermediate frequencies; this is called a dual-conversion or double-conversion superheterodyne. [9]
In order to achieve both good adjacent channel selectivity and image rejection, the double-conversion receiver uses two intermediate frequencies (IFs). The incoming radio frequency (RF) signal from the antenna is first mixed with a sinusoidal signal from the 1st local oscillator (LO) to give a high 1st IF frequency. Since the separation between ...
valve single conversion 8 band 15 10 6 1 Kenwood R-300 Hobbyist .17-30 dual conversion AM SSB 2.5 5 0 7.7 362x163x325 7 8 2 no [39] Kenwood: R-600 Hobbyist 1982-1985 .15-30 triple conversion AM LSB USB 2.7 6 5 3 2 [40] Kenwood QR-666 Hobbyist .17-.41, .525-30 dual conversion 30 band AM SSB 2.5 5 0 7.7 362x163x325 7 8 1 no [41] Kenwood R-1000 ...
Superheterodyne transmitter is a radio or TV transmitter which uses an intermediate frequency signal in addition to radio frequency signal. Types of transmitters
In the Direct conversion receiver, the signals from the antenna are only tuned by a single tuned circuit before entering a mixer where they are mixed with a signal from a local oscillator which is tuned to the carrier wave frequency of the transmitted signal. This is unlike the superheterodyne design, where the local oscillator is at an offset ...
Block diagram of a superheterodyne receiver. The RF front end consists of the components on the left colored red. In a radio receiver circuit, the RF front end, short for radio frequency front end, is a generic term for all the circuitry between a receiver's antenna input up to and including the mixer stage. [1]