The Panapet radio is a round novelty radio on a chain, first produced by Panasonic in the early 1970s to commemorate the World Expo in Osaka [1] Two chrome plated dials on the surface are for tuning and volume, and a tuning display is inset on the surface of the ball. The Panapet is AM band only - no FM. There is a jack for a mono earplug. The Panapet came in several colors including red, yellow, white, blue, purple and avocado green.
A Soviet clone of this radio is called Saratov, named after the city where it was manufactured. While being similar externally, it is fully different internally. It is a nine-transistor TRF receiver with transformerless audio amplifier, while the prototype is a six-transistor superheterodyne, and its audio amplifier uses transformers. The clone has no chain, but has metal ring between ball halves instead. A later clone, LW superheterodyne with transformerless audio amplifier by the same manufacturer is called Batiskaf (means bathyscaph), it has chain and dial and lacks metal ring between halves, like in original Panapet. Another later clone, similar to previous one, but without chain, was manufactured in Khmelnitsky, it has the 1980 Moscow Summer Olympics logo on its dial.
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. It was invented by French radio engineer and radio manufacturer Lucien Lévy. Virtually all modern radio receivers use the superheterodyne principle.
A transistor is a semiconductor device used to amplify or switch electrical signals and power. It is one of the basic building blocks of modern electronics. It is composed of semiconductor material, usually with at least three terminals for connection to an electronic circuit. A voltage or current applied to one pair of the transistor's terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Some transistors are packaged individually, but many more in miniature form are found embedded in integrated circuits. Because transistors are the key active components in practically all modern electronics, many people consider them one of the 20th century's greatest inventions.
In communications and electronic engineering, an intermediate frequency (IF) is a frequency to which a carrier wave is shifted as an intermediate step in transmission or reception. The intermediate frequency is created by mixing the carrier signal with a local oscillator signal in a process called heterodyning, resulting in a signal at the difference or beat frequency. Intermediate frequencies are used in superheterodyne radio receivers, in which an incoming signal is shifted to an IF for amplification before final detection is done.
An audio power amplifier amplifies low-power electronic audio signals, such as the signal from a radio receiver or an electric guitar pickup, to a level that is high enough for driving loudspeakers or headphones. Audio power amplifiers are found in all manner of sound systems including sound reinforcement, public address, home audio systems and musical instrument amplifiers like guitar amplifiers. It is the final electronic stage in a typical audio playback chain before the signal is sent to the loudspeakers.
The RCA connector is a type of electrical connector commonly used to carry audio and video signals. The name RCA derives from the company Radio Corporation of America, which introduced the design in the 1930s. The connector’s male plug and female jack are called RCA plug and RCA jack.
A regenerative circuit is an amplifier circuit that employs positive feedback. Some of the output of the amplifying device is applied back to its input to add to the input signal, increasing the amplification. One example is the Schmitt trigger, but the most common use of the term is in RF amplifiers, and especially regenerative receivers, to greatly increase the gain of a single amplifier stage.
A tuned radio frequency 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. Early examples could be tedious to operate because when tuning in a station each stage had to be individually adjusted to the station's frequency, but later models had ganged tuning, the tuning mechanisms of all stages being linked together, and operated by just one control knob. By the mid 1930s, it was replaced by the superheterodyne receiver patented by Edwin Armstrong.
In radio communications, a radio receiver, also known as a receiver, a wireless, or simply a radio, is an electronic device that receives radio waves and converts the information carried by them to a usable form. It is used with an antenna. The antenna intercepts radio waves and converts them to tiny alternating currents which are applied to the receiver, and the receiver extracts the desired information. The receiver uses electronic filters to separate the desired radio frequency signal from all the other signals picked up by the antenna, an electronic amplifier to increase the power of the signal for further processing, and finally recovers the desired information through demodulation.
A push–pull amplifier is a type of electronic circuit that uses a pair of active devices that alternately supply current to, or absorb current from, a connected load. This kind of amplifier can enhance both the load capacity and switching speed.
The term All American Five is a colloquial name for mass-produced, superheterodyne radio receivers that used five vacuum tubes in their design. These radio sets were designed to receive amplitude modulation (AM) broadcasts in the medium wave band, and were manufactured in the United States from the mid-1930s until the early 1960s. By eliminating a power transformer, cost of the units was kept low; the same principle was later applied to television receivers. Variations in the design for lower cost, shortwave bands, better performance or special power supplies existed, although many sets used an identical set of vacuum tubes.
The Regency TR-1 was the first commercially manufactured transistor radio, introduced in 1954. Despite mediocre performance, about 150,000 units were sold, due to the novelty of its small size and portability. Previously, transistors had only been used in military or industrial applications, and the TR-1 demonstrated their utility for consumer electronics, offering a prescient glimpse of a future full of small, convenient hand-held devices that would develop into calculators, mobile phones, tablets and the like. Surviving specimens are sought out by collectors.
In radio, a detector is a device or circuit that extracts information from a modulated radio frequency current or voltage. The term dates from the first three decades of radio (1888–1918). Unlike modern radio stations which transmit sound on an uninterrupted carrier wave, early radio stations transmitted information by radiotelegraphy. The transmitter was switched on and off to produce long or short periods of radio waves, spelling out text messages in Morse code. Therefore, early radio receivers could reproduce the Morse code "dots" and "dashes" by simply distinguishing between the presence or absence of a radio signal. The device that performed this function in the receiver circuit was called a detector. A variety of different detector devices, such as the coherer, electrolytic detector, magnetic detector and the crystal detector, were used during the wireless telegraphy era until superseded by vacuum tube technology.
A reflex radio receiver, occasionally called a reflectional receiver, is a radio receiver design in which the same amplifier is used to amplify the high-frequency radio signal (RF) and low-frequency audio (sound) signal (AF). It was first invented in 1914 by German scientists Wilhelm Schloemilch and Otto von Bronk, and rediscovered and extended to multiple tubes in 1917 by Marius Latour and William H. Priess. The radio signal from the antenna and tuned circuit passes through an amplifier, is demodulated in a detector which extracts the audio signal from the radio carrier, and the resulting audio signal passes again through the same amplifier for audio amplification before being applied to the earphone or loudspeaker. The reason for using the amplifier for "double duty" was to reduce the number of active devices, vacuum tubes or transistors, required in the circuit, to reduce the cost. The economical reflex circuit was used in inexpensive vacuum tube radios in the 1920s, and was revived again in simple portable tube radios in the 1930s.
An antique radio is a radio receiving set that is collectible because of its age and rarity.
The autodyne circuit was an improvement to radio signal amplification using the De Forest Audion vacuum tube amplifier. By allowing the tube to oscillate at a frequency slightly different from the desired signal, the sensitivity over other receivers was greatly improved. The autodyne circuit was invented by Edwin Howard Armstrong of Columbia University, New York, NY. He inserted a tuned circuit in the output circuit of the Audion vacuum tube amplifier. By adjusting the tuning of this tuned circuit, Armstrong was able to dramatically increase the gain of the Audion amplifier. Further increase in tuning resulted in the Audion amplifier reaching self-oscillation.
An AC/DC receiver design is a style of power supply of vacuum tube radio or television receivers that eliminated the bulky and expensive mains transformer. A side-effect of the design was that the receiver could in principle operate from a DC supply as well as an AC supply. Consequently, they were known as "AC/DC receivers".
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.
The National Panasonic Model RE-784A is a vacuum tube AM/FM table radio from the post-war era (1960s) manufactured by National Panasonic. The miniature tube-based circuitry follows the "All American Five" tube design, which allowed a more compact footprint of the radio; suited for sitting atop a fireplace mantle or to be mounted under a kitchen cabinet. One feature of the FM band for this radio is AFC tuning, that allowed the listener to "lock-in" an FM station without having to worry about station drifting or drops in audio volume associated with FM station tuning.
Olimpik — a series of Soviet produced superheterodyne portable radio receiver. The first model was developed in 1977 by the Ukrainian artist Mykola Lebid. The production was timed to coincide with the 1980 Summer Olympics in Moscow. Radio receivers were made at the Svitlovodsk plant Olymp in Ukraine. Some models were also manufactured by the production association Alatau in Kazakhstan.