Radio hat

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The June 1949 issue of Radio-Electronics showing the "Man-from-Mars, Radio Hat," modeled by a 15-year-old Hope Lange Radio Electronics Cover June 1949.jpg
The June 1949 issue of Radio-Electronics showing the "Man-from-Mars, Radio Hat," modeled by a 15-year-old Hope Lange

The radio hat was a portable radio built into a pith helmet that would bring in stations within a 20-mile (32 km) radius. It was introduced in early 1949 for $7.95 as the "Man-from-Mars Radio Hat." [1] Thanks to a successful publicity campaign, the radio hat was sold at stores from coast to coast in the United States.

Pith helmet

The pith helmet, also known as the safari helmet, sun helmet, topee, sola topee or topi, is a lightweight cloth-covered helmet made of sholapith. Pith helmets were often worn by European travelers and explorers, in the varying climates found in Africa, Southeast Asia, and the tropics, but have also been used in many other contexts. They were routinely issued to European military personnel serving overseas "in hot climates" from the mid-nineteenth to the mid-twentieth century.

Contents

The radio hat was manufactured by American Merri-Lei Corporation of Brooklyn N.Y. The company was a leading supplier of party hats, noise makers and other novelty items. Its founder, Victor Hoeflich, had invented a machine to make paper Hawaiian leis while still in high-school (1914), and by 1949 the company shipped millions of leis to Hawaii each year. An inventor and gadgeteer, [2] [3] [4] Hoeflich continued to develop and even sell machinery that manufactured paper novelty items. [5] [6]

Party hat

A party hat is generally a playful conical hat made with a rolled up piece of thin cardboard, usually with designs printed on the outside and a long string of elastic acting like a chinstrap, going from one side of the cone's bottom to another to secure the cone to the person's head. Its name originates with its use: Party hats are worn most often at birthday parties, especially by the guest of honor, with a significant minority being worn for New Year celebrations. In Britain the hat is made of paper and is the shape of a crown, and is most typically worn during a Christmas dinner. The party hat has its origins in the dunce cap worn by misbehaving or poorly performing schoolchildren from the mid-19th century to the early 20th century, with its festive decoration and society's positive attitude toward the wearer indicating a relaxation, abrogation, or even reversal of certain social norms: During the occasion in question, the wearer is permitted or encouraged to engage, rather than discouraged from engaging, in frivolous and foolish behavior for which the required wearing of the dunce cap would in other situations constitute a punishment. Party hats have originated in England

Battery-operated portable radios had been available for many years, but Hoeflich hoped a radio with innovative packaging and a publicity campaign could be a runaway success. The transistor had just been invented, but was still an expensive laboratory curiosity; the first pocket transistor radio was still 5 years away. This radio would have to use the existing vacuum tube technology and the tubes would be a prominent design feature. The loop antenna and the tuning knob were also visible. The hat was available in eight colors: Lipstick Red, Tangerine, Flamingo, Canary Yellow, Chartreuse, Blush Pink, Rose Pink and Tan. [7] [8]

Transistor radio portable radio receiver

A transistor radio is a small portable radio receiver that uses transistor-based circuitry. Following their development in 1954, made possible by the invention of the transistor in 1947, they became the most popular electronic communication device in history, with billions manufactured during the 1960s and 1970s. Their pocket size sparked a change in popular music listening habits, allowing people to listen to music anywhere they went. Beginning in the 1980s, however, cheap AM transistor radios were superseded by devices with higher audio quality such as portable CD players, personal audio players, boomboxes, and (eventually) smartphones, some of which contain radios themselves.

Vacuum tube Device that controls electric current between electrodes in an evacuated container

In electronics, a vacuum tube, an electron tube, or valve or, colloquially, a tube, is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied.

Product introduction

The radio hat interior; the headphone could be on either side. Radio Hat Interior.jpg
The radio hat interior; the headphone could be on either side.

In March 1949, Victor Hoeflich held a press conference to introduce the "Man from Mars, Radio Hat". Hoeflich knew a picture would tell the story so he had several teenagers modeling the radio hats for the reporters and photographers. Soon pictures and news stories appeared in newspapers coast to coast. [9] [10] The articles typically included a photo of a young lady wearing the hat and a six-paragraph story. The radio hat also received widespread coverage in magazines. This included do-it-yourself magazines such as Popular Mechanics, [11] Popular Science, [12] Mechanix Illustrated, [13] and Radio-Electronics. There was also coverage in general-audience magazines such as Life, Time, [14] Newsweek, and The New Yorker. [6]

The radio hat was sold in department stores and by mail order. [1] A Van Nuys, California service station chain sold the hats as a promotion item to customers who purchased gasoline. [15] The massive publicity did not lead to lasting sales. Advertisements for the radio hat stopped in early 1950. In a 1956 interview, Hoeflich said the company still got orders for the hat even though it was long out of production. [5]

Hugo Gernsback, the Editor of Radio-Electronics, was impressed with the radio hat and the June 1949 issue had a two-page article describing the circuitry and construction of the radio. The cover photograph shows a 15-year-old Hope Lange wearing a Lipstick Red hat. [8] She went on to become an award-winning stage, film, and television actress. She was nominated for the 1957 Academy Award for Best Supporting Actress for her role as Selena Cross in the film Peyton Place. [16] [17]

Hugo Gernsback Luxembourgian American inventor, writer, editor, and publisher

Hugo Gernsback was a Luxembourgish-American inventor, writer, editor, and magazine publisher, best known for publications including the first science fiction magazine. His contributions to the genre as publisher–although not as a writer–were so significant that, along with the novelists H. G. Wells and Jules Verne, he is sometimes called "The Father of Science Fiction". In his honour, annual awards presented at the World Science Fiction Convention are named the "Hugos".

<i>Radio-Electronics</i>

Radio-Electronics was an American electronics magazine that was published under various titles from 1929 to 2003. Hugo Gernsback, sometimes called by Americans as The Father of Science Fiction, started it as Radio-Craft in July 1929. The title was changed to Radio-Electronics in October 1948 and again to Electronics Now in July 1992. In January 2000 it was merged with Gernsback's Popular Electronics to become Poptronics. Gernsback Publications ceased operations in December 2002 and the January 2003 issue was the last. Over the years, Radio-Electronics featured audio, radio, television and computer technology. The most notable articles were the TV Typewriter and the Mark-8 computer. These two issues are considered milestones in the home computer revolution.

Hope Elise Ross Lange was an American film, stage, and television actress.

Circuit description

The circuit was on a flexible liner that fit inside the hat. Radio Hat Chassis.jpg
The circuit was on a flexible liner that fit inside the hat.

Radios at this time usually were powered by the AC mains. They used vacuum tubes that had a 6 or 12 volt filament supply that heated the cathode; and a 100 to 300 volt anode (or B+) supply. The technological advances in World War II for mobile radios produced inexpensive low power vacuum tubes. The radio hat had an external battery pack that provided 1.5 volts for the filaments and the 22.5 volt B+ supply. These were much safer voltages for use in a hat, especially since the full plate voltage is dropped across the earphone. This technique was commonly used in many simple radios, some having ninety or more volts present across the head or earphones. The battery pack would power the radio for up to 20 hours.

The radio received the AM broadcast band (540 kHz to 1600 kHz) and was tuned by a knob between the two tubes. (Table top or console radio receivers of the day used 5 or 6 tubes to provide better performance.)

Schematic

The 1S5 vacuum tube converted the radio signal to audio and the 3V4 amplified the audio for the headphone. Radio Hat Circuit.jpg
The 1S5 vacuum tube converted the radio signal to audio and the 3V4 amplified the audio for the headphone.

The 1S5 tube functioned as a regenerative detector. Audio detected by the 1S5 was resistance-coupled to the 3V4, where it was amplified and supplied to the earphone.

The detector was provided with a cathode feedback level well into the oscillation range by the 330 pF capacitor. The received carrier blocked the oscillations, allowing strong local stations to be received clearly. In addition, the loop antenna was part of the resonant tuning circuit, resulting in near-unity coupling between the antenna and the detector, which helped provide a high enough level of carrier for the blocking function. A regenerative detector operated in this mode is sometimes called a superregenerative detector, but in this circuit there was no separate quenching oscillator. The blocking signal was ideally at the same frequency as the oscillation, as opposed to the usually lower frequency employed in a true supperregenerative detector.

The regenerative detector in the radio hat had adequate sensitivity to receive stations much more distant than the stipulated twenty-mile range, but distant stations would not have had a strong enough carrier to block the oscillations and so would be received with an objectionable heterodyne, audible as an astable squealing noise. Furthermore, the loop antenna was somewhat directional. This was a limitation for a portable radio; the signal level could vary when the listener turned their head. If the target station was accidentally nulled, the carrier signal could fall below blocking level, resulting in an annoying squealing heterodyne similar to that present on stations outside the normal range of the radio.

Related Research Articles

Superheterodyne receiver radio receiver; uses frequency mixing to convert a received signal to a fixed intermediate frequency which can be more conveniently processed than the original carrier frequency;virtually all modern radio receivers use the superheterodyne principle

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 US engineer Edwin Armstrong in 1918 during World War I. Virtually all modern radio receivers use the superheterodyne principle.

Transmitter Electronic device that emits radio waves

In electronics and telecommunications, a transmitter or radio transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating current, the antenna radiates radio waves.

Crystal radio

A crystal radio receiver, also called a crystal set, is a simple radio receiver, popular in the early days of radio. It uses only the power of the received radio signal to produce sound, needing no external power. It is named for its most important component, a crystal detector, originally made from a piece of crystalline mineral such as galena. This component is now called a diode.

In electronics, an avalanche diode is a diode that is designed to experience avalanche breakdown at a specified reverse bias voltage. The junction of an avalanche diode is designed to prevent current concentration and resulting hot spots, so that the diode is undamaged by the breakdown. The avalanche breakdown is due to minority carriers accelerated enough to create ionization in the crystal lattice, producing more carriers which in turn create more ionization. Because the avalanche breakdown is uniform across the whole junction, the breakdown voltage is nearly constant with changing current when compared to a non-avalanche diode.

A continuous wave or continuous waveform (CW) is an electromagnetic wave of constant amplitude and frequency, almost always a sine wave, that for mathematical analysis is considered to be of infinite duration. Continuous wave is also the name given to an early method of radio transmission, in which a sinusoidal carrier wave is switched on and off. Information is carried in the varying duration of the on and off periods of the signal, for example by Morse code in early radio. In early wireless telegraphy radio transmission, CW waves were also known as "undamped waves", to distinguish this method from damped wave signals produced by earlier spark gap type transmitters.

This is an index of articles relating to electronics and electricity or natural electricity and things that run on electricity and things that use or conduct electricity.

Regenerative circuit

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 so as 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.

Tuned radio frequency receiver

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.

Radio receiver radio device for receiving radio waves and converting them to a useful signal

In radio communications, a radio receiver, also known as a receiver, wireless or simply 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.

Grid-leak detector

A grid leak detector is an electronic circuit that demodulates an amplitude modulated alternating current and amplifies the recovered modulating voltage. The circuit utilizes the non-linear cathode to control grid conduction characteristic and the amplification factor of a vacuum tube. Invented by Lee De Forest around 1912, it was used as the detector (demodulator) in the first vacuum tube radio receivers until the 1930s.

Neutrodyne

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". to prevent parasitic oscillations which caused "squealing" or "howling" noises in the speakers of early radio sets. In most designs, a small extra winding on each of the RF amplifiers' tuned anode coils was used to generate a small antiphase signal, which could be adjusted by special variable trim capacitors to cancel out the stray signal coupled to the grid via plate-to-grid capacitance. The Neutrodyne circuit was popular in radio receivers until the 1930s, when it was superseded by the superheterodyne receiver.

Radio receiver design includes the electronic design of different components of a radio receiver which processes the radio frequency signal from an antenna in order to produce usable information such as audio. The complexity of a modern receiver and the possible range of circuitry and methods employed are more generally covered in electronics and communications engineering. 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 which modulated the radio signal at the time of transmission in a communications or broadcast system.

Crystal detector

A crystal detector is an obsolete electronic component in some early 20th century radio receivers that used a piece of crystalline mineral as a detector (demodulator) to rectify the alternating current radio signal to extract the audio modulation which produced the sound in the earphones. It was the first type of semiconductor diode, and one of the first semiconductor electronic devices. The most common type was the so-called cat whisker detector, which consisted of a piece of crystalline mineral, usually galena, with a fine wire touching its surface. The "asymmetric conduction" of electric current across electrical contacts between a crystal and a metal was discovered in 1874 by Karl Ferdinand Braun. Crystals were first used as radio wave detectors in 1894 by Jagadish Chandra Bose in his microwave experiments. who first patented a crystal detector in 1901. The crystal detector was developed into a practical radio component mainly by G. W. Pickard, who began research on detector materials in 1902 and found hundreds of substances that could be used in forming rectifying junctions. The physical principles by which they worked were not understood at the time they were used, but subsequent research into these primitive point contact semiconductor junctions in the 1930s and 1940s led to the development of modern semiconductor electronics.

In electronics, motorboating is a type of low frequency parasitic oscillation that sometimes occurs in audio and radio equipment and often manifests itself as a sound similar to an idling motorboat engine, a "put-put-put", in audio output from speakers or earphones. It is a problem encountered particularly in radio transceivers and older vacuum tube audio systems, guitar amplifiers, PA systems and is caused by some type of unwanted feedback in the circuit. The amplifying devices in audio and radio equipment are vulnerable to a variety of feedback problems, which can cause distinctive noise in the output. The term motorboating is applied to oscillations whose frequency is below the range of hearing, from 1 to 10 hertz, so the individual oscillations are heard as pulses. Sometimes the oscillations can even be seen visually as the woofer cones in speakers slowly moving in and out.

Magnetic detector

The magnetic detector or Marconi magnetic detector, sometimes called the "Maggie", was an early radio wave detector used in some of the first radio receivers to receive Morse code messages during the wireless telegraphy era around the turn of the 20th century. Developed in 1902 by radio pioneer Guglielmo Marconi from a method invented in 1895 by New Zealand physicist Ernest Rutherford it was used in Marconi wireless stations until around 1912, when it was superseded by vacuum tubes. It was widely used on ships because of its reliability and insensitivity to vibration. A magnetic detector was part of the wireless apparatus in the radio room of the RMS Titanic which was used to summon help during its famous 15 April 1912 sinking.

Electrolytic detector

The electrolytic detector, or liquid barretter, was a type of detector (demodulator) used in early radio receivers. First used by Canadian radio researcher Reginald Fessenden in 1903, it was used until about 1913, after which it was superseded by crystal detectors and vacuum tube detectors such as the Fleming valve and Audion (triode). It was considered very sensitive and reliable compared to other detectors available at the time such as the magnetic detector and the coherer. It was one of the first rectifying detectors, able to receive AM (sound) transmissions. On December 24, 1906, US Naval ships with radio receivers equipped with Fessendon's electrolytic detectors received the first AM radio broadcast from Fessenden's Brant Rock, Massachusetts transmitter, consisting of a program of Christmas music.

Detector (radio)

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 had only to distinguish 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.

Reflex receiver

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.

Autodyne Wikimedia disambiguation page

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.

Optical heterodyne detection is a method of extracting information encoded as modulation of the phase, frequency or both of electromagnetic radiation in the wavelength band of visible or infrared light. The light signal is compared with standard or reference light from a "local oscillator" (LO) that would have a fixed offset in frequency and phase from the signal if the latter carried null information. "Heterodyne" signifies more than one frequency, in contrast to the single frequency employed in homodyne detection.

References

  1. 1 2 "Ad for radio hat". Popular Science. Vol. 155 no. 4. Popular Science Publishing. October 1949. p. 89.
  2. Hoeflich, Victor T., "Machine for making convoluted structures of flexible materials", US Patent 1888197, issued November 15, 1932.
  3. Hoeflich, Victor T., "Method of manufacturing noise", US Patent 2280582, issued April 21, 1942.
  4. Hoeflich, Victor T., "Mouthpiece for sound-producing devices", US Patent 2607162, issued August 19, 1952.
  5. 1 2 Soule, Garner (January 1956). "He puts the noise in New Years". Popular Science. Vol. 168 no. 1. pp. 132–135, 254–256.
  6. 1 2 Gill, Brendan (April 16, 1949). "The Talk of the Town, Revolutionary". The New Yorker. p. 19.
  7. "Radio Hat advertisement". Radio Electronics. 2 (11): 75. August 1949.
  8. 1 2 "The Radio Hat". Radio Electronics. 20 (9): 4, 32–33. June 1949. Cover description: The Radio Hat, posed by Hope Lange. page 4 "The Radio Hat is made in such gay colors as canary yellow, lipstick red, turquoise, chartreuse, tangerine, lavender, blue, and cerise for teen-agers, and in tan, gray, green-gray, and blue-gray for adult." page 33
  9. "Radio Goes on the Hair in Your Hat". Kingsport News. March 25, 1949. p. 23. This Newspaper Enterprise Association (NEA) wire service story was printed in many newspapers, including these: Ames Daily Tribune (Ames, Iowa on March 28) 1949; The Daily Mail (Hagerstown, Maryland on April 1); The Lima News (Lima, Ohio on April 11); Lowell Sun (Lowell, Massachusetts on April 7) The Brownsville Herald, (Brownsville, Texas on June 3).
  10. "Wired for sound through his new Radio Hat". Jefferson City Post-Tribune. March 25, 1949. p. 6. This Associated Press Wirephoto featured a boy, Ed Donegan of Brooklyn NY.
  11. "Radio and Electronic Hints for Today". Popular Mechanics. Vol. 91 no. 1. Popular Mechanics Company. July 1949. p. 224.
  12. "Sun Hat Has Built-In Radio". Popular Science. Vol. 154 no. 6. June 1949. p. 119.
  13. Peterson, West (September 1949). "GADGETS Can Make Your FORTUNE". Mechanix Illustrated. 41 (5): 55–57, 162–166.
  14. "Ben, Joe & the Kiddies". Time. Vol. 52 no. 12. March 21, 1949.
  15. "Craig Stations Introduce Unique Radio Headwear". Van Nuys News. June 13, 1949. p. 18.
  16. Polgreen, Lydia (December 22, 2003). "Hope Lange, Versatile Actress And Emmy Winner, Dies at 70". The New York Times. p. 7.
  17. "Hope Lange: Sensitive actress nominated for an Oscar for her role in Peyton Place". The Independent. December 23, 2003. Retrieved March 3, 2009. She was also in the 1974 film, Death Wish.