Radio Related Links
ARRL Website
Atwater Kent Website

The Crosley Radio Gallery




ARRL WebsiteARRL Website
Hiram Percy Maxim, founder of the American Radio Relay League and the "father of Ham Radio."

The American Radio Relay League was established, under the early leadership of Hiram Percy Maxim and Clarence Tuska, as a fraternity of amateur radio operators who would adhere to common sense standards of operation in the early days of 20th Century experimental radio. A century later, the League has grown to membership approaching three-hundred-thousand members, and it remains a strong and viable organization for the protection and advancement of Ham Radio training, legal intervention, and support of licensed amateur radio "ham" operators.

The League's magazines and educational publications have documented the development of radio over the course of more than a Century, and it has managed to work with the FCC over the years to protect the rights of Ham Radio Operators and the frequencies allocated for the hobby.

John DeMajo and The Museum of Yesterday are proud of our ARRL Life Member status which dates back to 1960 when our founder Mr. DeMajo, as a young teenager, joined the League upon receiving his first FCC radio operator's license. The photo below shows our founder and chairman, who now holds the highest classification ham radio license (Extra Class), and certification as an ARRL license instructor, at the controls of the Hiram Percy Maxim Memorial Radio Station "W1AW" at ARRL headquarters in Newington, Connecticut. It was taken during the 2014 celebration of the 55th anniversary of the issuance of Mr. DeMajo's radio call sign K5HTZ. .


A close-up view of the K5HTZ Radio Ham Shack located in the basement "bunker" at the Museum Of Yesterday. The station's range is confirmed to be approximately 2000 miles with 100 watts of power, and internationally through the Western Hemisphere when the 1200 watt amplifier is in use. Below is a partial listing of states and countries that have been contacted in recent weeks using the above rig. Many of these contacts were made using just 100 watts of power.

9/1/2020 and 10/13/2020
The document above is a sample of a U.S. Federal Communications Commission issued amateur radio license. Obtaining a "ham" license requires the applicant to sit for a series of Federal government issued tests in order to demonstrate his or her proficiency in the technical requirements and knowledge of the rules and regulations required in order to safely operate an amateur radio transmitting station. There are several classes of licenses available. Each "class" of license requires possession of certain skills. The higher the class of license, the more difficult the test that must be successfully passed in order to obtain it.

The device shown above is the dreaded "Wouff-Hong."
This example was an award bestowed at the 1938 ARRL convention. It was recently acquired by The Museum Of Yesterday.

The story of the "Wouff-Hong"

Amateur radio, while under the control of the Federal Communications Commission today, has always been to some extent a "self policed" hobby. Conscientious amateur radio operators pride themselves on operating stations that are clean, safe, well regulated, and which adhere to the law. In the case of those rare operators and hacks who do not adhere to the standards, they are usually called down by their licensed peers even before they come to the attention of the Federal regulators. The FCC imposes stiff fines on wayward members of the amateur radio service, just as it does for those licensees in the commercial broadcast industry.

In the early days of Radio, the radio spectrum had become a playground for experimenters who were operating all manner of spark transmitters and other unregulated radio devices that often impeded critical communications between ships at sea and other public safety and broadcast efforts. Since the government had not yet become the official regulator of the radio spectrum, amateurs, particularly those who subscribed to the standards of the American Radio Relay League, felt that there was a need to present a fictitious symbol of an instrument of punishment for those early hams who didn't operate courteously or in conformance with the law. Out of this early period evolved the instrument of torture known as the "Wouff-Hong." It is believed that league founder Hiram Percy Maxim (pictured above) offered the Wouff-Hong as that very symbol in 1919. That year, Maxim wrote an article in QST magazine, the official journal of the ARRL, in which he offered the Hong as a representation of the spirit of self-policing of the radio bands. Today, the Secret Society of the Wouff-Hong convenes annually at ARRL conventions, and the original Wouff-Hong, presented to the league by Maxim in 1919, hangs in the office of the League's secretary in the Newington, CT. headquarters of the organization.

The manner in which the Hong was to be applied to wayward ham radio operators was never really openly discussed, however in viewing it, it is not hard to imagine how those early wireless operators envisioned it's application. The "Wouff-Hong" shown above, which was presented at the 1938 ARRL Convention, now stands guard over the amateur radio service at the Museum Of Yesterday's communications history collection.



Prior to the latter fifth of the 20th Century, obtaining an amateur radio license required the applicant to be proficient in the International Telegraph Code, which was commonly referred to as "Morse Code." The speed requirements and proficiency of the operator depended on the grade of license for which the applicant was testing, and minimum accurate copy speeds ranged from 5 to 23 words-per-minute. Most license tests were given by FCC field engineers at local FCC offices. Many of us older hams remember getting up early in the morning and traveling to the nearest FCC field office where we sweated out these code tests.

The license preparation for aspiring hams usually involved individual or group practice of sending and receiving code. The same procedure applied to operators in the military or shipboard radio services. In the next few photos, you will see some of the simple tube type code practice oscillators that were used by most people in learning and practicing the code. Bud, T. A. McElroy, TAC, AMECO and others were among the brands commonly found in radio schools and ham shacks across the nation. This section of our site pays homage to the lowly code practice oscillator.

A personal recollection from museum founder and chairman John DeMajo:

The code practice oscillator is certainly no stranger. I was barely learning the letters of the alphabet when my uncle, who was a ham operator, began to teach me the radio-telegraph code, often referred to as Morse Code. We would sit across the table and he would send me simple stories and messages in code, that I would have to decipher. Later, when I was a freshman in high school, the ham radio club would meet at 7 P.M. each Monday evening in the school library, and again we would employ an oscillator like the one shown above, to teach and learn code with the hope that this extracurricular activity would enable members to sit for an FCC license test. These simple sound generating devices also doubled as signal monitors to allow us to hear our own sending when using an actual transmitter. Whether it was individual code practice at home, ham radio clubs, or military training, just about every CW radio operator owes some portion of his skills to these simple code tone generating devices.

As modern technology eliminated the need for CW or code based radio transmissions, for all but the most die-hard hams who still like to operate in the CW mode for sport, the code requirements were dropped from most amateur radio license classes. Similarly, ship-to-shore code stations began to be phased out, and most vessels today rely on satellite communications when at sea.

The Oscillatone, by T. A, McElroy Company, was one of the first commercially packaged one-tube code oscillators. Designed with WW-II military service in mind, the single, dual purpose 117 volt filament tube made it possible to produce an economical transformerless code practice oscillator in a small package. With the introduction of the 117L7-M7GT electron tube, which contained both a half wave rectifier and pentode amplifier in the same glass envelope, a number of wartime and post-war manufacturers quickly applied this tube to these simple code practice oscillators as well as inexpensive portable phonograph amplifiers.
A recently acquired, near mint condition T.A.C. code oscillator manufactured for WW-II use. These units were around in civilian service for several years after the war, and they were found in many 1950s ham shacks.
Cut sheet from 1947Allied Radio Corporation catalog showing the MS-710 above.
By today's standards, the original cost of 9.00 would not even have covered one-third of the shipping costs for the unit that the museum has recently acquired.
During the 1930s, railroad telegraphy expanded as even remote rail stations became the local outlets for Western Union in smaller cities and towns. The Instructograph, an automatic code practice device using punched paper to create code characters, went into wide spread use for training of railroad and Western Union employees. With the onset of World War II, the Instructograph company began manufacturing devices used to train military personnel. After the war, war surplus Instructographs found their way into training schools and ham radio clubs where a new generation of commercial and ham operators were faced with learning to send and receive the code.
Although amateur licenses in the 1930s required code proficiency, this mid-1930s vintage license manual contained all of the study information needed to successfully pass all classes of amateur tests, and at a price of a mere 25 cents. Today, although the code requirement no longer exists, there are separate 1000 plus page manuals for each class of license. The approximate cost for a license manual is now $30. This indicates the technical advances of today that amateur operators must understand in order to be proficient in the hobby.


Beginning in the early 1900s, lists of amateur radio operators were published on a somewhat regular basis. These indexes of licensed radio operators and their call signs, served as verification and location of stations. In the very early years, the "Blue Book" of licensed operators was the official publication. Beginning around 1919, the U.S. Commerce Department began to publish annual lists of amateur stations. Within a few years, a publication was established under the name "AMATEUR RADIO CALLBOOK MAGAZINE". These call books remained as the standard listing until the advent of the Internet at which time the FCC began operating their own on-line database. Today, organizations such as QRZ, the ARRL, and other Ham support groups have made the FCC data available on their web sites as well. For a history and examples of the "Blue Book" and the "Amateur Radio Call book," click this link

Click Here

Thoughts From Our Founder:
In the middle years of the 20th Century, there were no computers, cell phones or video games. Entertainment for young inquisitive minds was limited to radio and later TV, with shows such as "Watch Mr. Wizard," and young electronics enthusiasts turned to Ham Radio as a popular hobby that permitted the expression of electronics competency. Of course things were simpler then from a technical and financial standpoint. Single Sideband, Packet, FM and UHF were just things being talked about. For the average young ham of the 1950s, it was CW in the form of home made transmitters that usually were born from the remnants of old converted receivers, audio equipment, surplus WW-II military gear, and later from scavenged television parts.

In those days, thoughtful and community supportive owners of the "mom and pop" radio repair shops that were still in abundance, often saved old sets and parts which they gladly offered to aspiring amateur radio operators. Many of today's seasoned Hams, got their start with home-made transmitters that used tubes such as 6L6, 807s and old television sweep amplifier tubes. Much of the rewards of the hobby came with the satisfaction of building one's own "rig" and getting on the air thanks to one's own ingenuity.

Today, Ham radio equipment has become much more complex, and many of today's Hams are on a technical level equating to a university trained electronics engineer or professional technician. On the other hand, many Hams are again discovering that same DIY satisfaction through kit built radios, devices such as the Raspberry Pi, and construction of projects featured in present day magazines and web sites.

It is important to be aware that many of today's electronic conveniences began as experiments in the realm of Ham radio. The spirit of ham radio is still very much alive, and this very rewarding hobby is something that today's youth should have an opportunity to rediscover.


"Rock Bound"
Examples of amateur radio, commercial broadcast, and industrial crystals

Prior to the digital age, commercial radio stations, and many amateur radio stations, used quartz crystals as a means of frequency control. The crystal, when cut and ground to size, oscillated at a designed frequency with exceptional stability, especially when temperature remained constant. Many commercial non-broadcast applications also used crystals to produce RF for process purposes such as RF powered ovens in factories. Amateur operators in the "novice" class were restricted to the use of crystal frequency control. This limitation was an incentive for the operator to upgrade to the "General" class license which permitted the use of variable frequency control. A "rock bound" amateur had to possess a crystal for each frequency on which operation was desired, which even at 1950s prices, could get fairly expensive.


A crystal oscillator is an electronic oscillator circuit that uses a piezoelectric resonator, a crystal, as its frequency-determining element. Crystal is the common term used in electronics for the frequency-determining component, a wafer of quartz crystal or ceramic with electrodes connected to it. A more accurate term for it is piezoelectric resonator. Crystals are also used in other types of electronic circuits, such as crystal filters. (Wikipedia)

Above: The inside of a typical modern Quartz crystal. A quartz plate, specially ground to oscillate at a specific frequency, is sandwiched between two plates of conductive metal. As current is applied from the oscillator circuit, the crystal's oscillations govern the flow of electrons, thereby producing RF energy at the desired frequency, or else acting to filter RF signals which are different from the crystal's resonant frequency.

The crystal tray below illustrates one ham's novel way of keeping his crystals readily accessible.

Because of the costs associated with having to purchase a separate crystal for each frequency on which a Ham transmitter was operated, many soon learned how to "grind" their own custom crystals. This "do-it-yourself" crystal kit from Crystal Products, Inc. of Kansas, MO., was one way to beat the high cost of ready-made crystal purchases.

Despite the fact that there are more than 800,000 licensed Ham radio operators in the world today, the origin of the term "HAM," as a metaphor for Amateur Radio Operator, is not that well known.

Its origin can be traced to a group of three radio experimenters and engineering students in the Harvard Radio Club. At the time, radio was in its infancy, and radio station call letters were usually self-assigned by the owner of the particular station. In the case of the three Harvard students, whose names were ALBERT S. HYMAN, BOB ALMY and POOGIE MURRAY, they first decided to call their station "HYMAN-ALMY-MURRAY". Shortly thereafter, as call signs using letters or numbers became the norm, the men changed their call letters to "HAM". For whatever reason, their call letters became synonymous with amateur radio, and the term remains today.
The following photos are of amateur radio related equipment contained in the Museum Of Yesterday's permanent collection. Arranged by manufacturer, the items in this gallery provide a good cross-sectional understanding of the range of equipment Ham radio operators and commercial communications entities had available to them in the mid-20th Century.
Abbott Instruments Company was actively involved in the development and manufacture of what came to be known as "Ultra Short Wave" spectrum radios in the era prior to, and throughout World War-II. In the mid 1930s, frequencies above 30Mhz were mostly uncharted territory. Then came the Cairo Convention of 1938 which opened the 5.5 and 2.5 meter bands to ham operators, while taking away the 40 meter band. HyTron Company, and other manufacturers were introducting tubes, capable of reaching the frequencies above 100 Mhz. Early transmitters for these bands consisted of oscillators which resembled plumbing fixtures more so than electronic devices. With the specter of an approaching war, the armed forces realized that they would need reliable short-range communications on the battle fields of Europe as well as for Civil Defense Agency use at home, therefore, development of VHF transceivers became a priority for companies such as Abbott. Abbott was one of the first companies to deploy the newly developed HY-615 and 2C26/HY-75 tubes in commercially produced transceivers. Shown below are two of the Abbott radios, in the museum's collection, that were around in the period beginning in 1941, and throughout the war.
Above and below: The museum's exceptionally rare World War II vintage Abbott TR-4 "Ultra-Short Wave" VHF transceiver. Following "re-capping" and minor cleanup in the museum's restoration shop, we are pleased to report that this nearly eighty-year-old relic of World War II is fully operational and able to perform just as it did in the year 1941.
Rear view of the 1941 TR-4 showing the vintage HY-615 receiving and 2C26/HY-75 transmitting tubes. It was also one of the first devices to commercially deploy the recently introduced (at the time) "loctal" tube (shown to the right of the HY-615).
The ad above, introducing the Abbott TR-4 as suited for Civil Defense purposes, appeared in the December 1941 issue of QST magazine, just days before the surprise bombing of Pearl Harbor.
By the beginning of World War-II, a second version of the Abbott 2-1/2 meter transceiver had come on the scene. This model DK-3 is a battery powered Abbott transceiver from early 1940s. It was specifically intended for use by the Signal Corps. Unlike the TR-4, the DK-3 combined the transmitter and receiver section into a single stage, thereby eliminating the high voltage demands of the previous sets. After the end of the war, many of these radios found their way to the surplus market. The museum's DK-3 was still being used in the late 1940s, as a mobile field radio, by radio and television station WHHI of Hilton Head South Carolina.
AMECO model "CN" 144 megacycle converter for 2-meter VHF reception on an HF receiver
Note the use of Nuvistor tubes. The Nuvistor, introduced in the early 1960s and intended for high frequency RF applications, was the final technological development in progression of the tube applications, occurring just prior to the end of the vacuum tube era.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

While Ameco's products enjoyed a respectable share of market acceptance, mainly because of their reasonable price tags and build-it-yourself kit inducement, none of their other products have realized the present day nostalgic popularity of their AC-1 Novice Transmitter Kit (shown above).

Far from the value of its 1950s price tag of $15, today almost impossible to find original condition AT-1 transmitters are drawing prices in excess of $300. A "bare bones" rig for budget strapped Novice class operators of that post-war era, the AC-1 was highly advertised in radio magazines. Because of the apparent successful sales and nostalgic significance to today's "baby boomer" hams, remaining AC-1s are highly sought after and at disproportionate costs whenever they do become available.

Currently, there are quite a few articles and You Tube videos available highlighting this simple little transmitter. We have provided a link below to one such video (by Bonnie Ramirez), and you can see the schematic and technical information by clicking the photo above.


The museum's restored AMECO AC-1 CW transmitter powering up into a 7.5 watt dummy load on 40 meters.

AMECO Model TX-62 was a popular late 1950s phone transmitter for the VHF 6 and 2 Meter bands.
In some of the Andy Griffith TV shows from the 1960s, an Ameco TX-62 can be seen on the table behind Andy's sheriff desk.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

Click image to see owner's manual
The AMECO Model TX-62 had an accessory known as the VFO-621. It permitted variable frequency control of the TX-62.
Another amateur radio accessory by AMECO is this PT-2 receive preamplifier and transmitter-receiver relay
The AMECO Model CP5 was sold in conjunction with the AMECO code training course shown below. Unlike many of the World War II and post war units that employed 117 volt filament dual purpose tubes, this oscillator was designed around a 50C5 oscillator tube and a 35W4 rectifier.
In addition to electronic equipment, AMECO also produced educational material for the radio operator. One recent addition to the museum's collection is a recorded course designed to teach radio-telegraph code to hams and commercial operators. It came in the form of a set of 78 RPM phonograph records. A set of these original recordings resides in the museum library.

The Gonset Communicator was a series of vacuum tube VHF AM radio transceivers that were widely sold in the 1950s and early 60s. They were designed by Faust Gonset and manufactured by the Gonset Division of L. A. Young Spring and Wire Corp. Models were built for amateur radio, aircraft radio and U.S. Civil Defense use. The Gonsets were among the first commercial radios available for the post-World War II amateur bands and helped popularize VHF for amateurs.

The Gonset Communicators were packaged in a square box with a carrying handle and a UHF connector for the antenna on top, making them quite portable. Early models had a magic eye tube tuning indicator in front. The configuration earned them the name "Gooney Box." The radios could operate from 110 volt AC mains, or 6 or 12 volt DC from a car battery. A simple whip antenna could be plugged into the antenna connector on top. The transmit/receive switch was on the front panel, not the microphone. The Gonset could also be connected to an external speaker and used as a public address (PA) system.

The Gonset's receiver was manually tuned over the unit's frequency range with an analog dial, while the transmitter frequency was controlled by a crystal oscillator. The original model had a single jack on the front panel for an FT-243 style crystal. A chain of frequency multipliers allowed crystals in the 8 MHz range to be used. Many such crystals were available as military surplus in the 1950s. Later models had jacks for four crystals with a switch to select which one to use. Models were available for the 6 meter and 2 meter amateur bands, as well for as the VHF aircraft air band where they were often used as ground stations at smaller airfields. The civil defense model was painted yellow with CD insignia, and was available for the 6 and 2 meter bands. The 2 meter model was also used for the Civil Air Patrol, and could cover CAP frequencies which were adjacent to the 2 meter amateur band.

The first model, introduced in the November 1952 QST Magazine, sold for $189.90. The model II, introduced in 1954 cost $230. It added the bank of transmit crystals and included knobs for the transmitter tuning controls, which required a screwdriver in the original. The model III was white and had a meter instead of the magic eye. The model IV switched to a lower profile package.
(Cited from Wikipedia)

Below: Original Gonset model shown beside a Model II version of the popular 1950s two meter transceiver.

Above: A rear view of the original 1952 model Gonset transceiver.
These devices were popular with "mobile" hams on a budget

"The Radio Man's Radio"

The Echophone EC-1, popular during World War II as "The GI's Radio."

Hallicrafters purchased Echophone Co. in the 1930s in order to obtain Echophone's RCA manufacturing license. Although the EC-1 series was manufactured during the manufacturing blackout that resulted from World War II, Hallicrafters was able to build and sell these radios, with the understanding that they would only be delivered to active military service persons in order to improve morale among our service men and women on the war front. For that reason, Hallicrafters elected to resurrect the Echophone name despite the fact that they had been manufacturing their products under the Hallicrafters banner for several years preceding the war.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)


This is the Hallicrafters Model S-41 receiver. It is an important addition to the museum's collection because it represents the transition between the Echophone Radio Manufacturing Company and The Hallicrafters Company. Note that it's appearance is very similar to the Echophone EC-1 shown above. It was, however, a transition radio that led to the Hallicrafters S-9 and the Sky Buddy S-19 which is shown below.

The Hallicrafters Company was founded by William J. Halligan, a former parts salesman for McMurdo, who had a desire to build custom fabricated communications grade radios. The exact history of the company, which was intertwined in mergers between Halligan's firm, McMurdo-Silver, Howard Radio and Echophone, is somewhat cloudy. An excellent research paper by Alan Douglas, posted on an Internet chat list in 2007, is the most thoroughly researched document thus far on the history of Hallicrafters. That document can be viewed by clicking on the provided trademark link below.


"At the beginning and the end"

Hallicrafters S-19 "Sky Buddy" was one of the first in a line of hobbyist communications receivers made by the Hallicrafters Company of Chicago, IL. Through most of the Hallicrafters' production, models designated as SX- were high end commercial receivers, often used by police, public service entities, and serious ham radio operators. whereas the S- series was a lower priced version of the same basic design that was intended for short wave listener and hobby use.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

In contrast, at the end of their realm as one of America's top four recevier manufacturers, Hallicrafters released a nostalgic version of the Sky Buddy for a new generation of hobbyists in the 1960s. The Sky Buddy II, also known as the model S-119, like it's 1930s namesake, was a basic multi-band superhet designed around tubes of that era. Because the S-119 is a "baby boomer" nostalgia radio for many, the prices of recently available sets on the antique market are drastically out of proportion with radios from the period.

While the Sky Buddy quickly became a popular receiver with short wave listeners and hams on a budget, the high end "SX" series, was the mainstay of the company's business. Designed for commercial and military service, the SX-11 began what would be a line of high end receivers that were produced throughout the company's history. The SX-11 above, and the 1937 SX-16 below, were two of Hallicrafters' early serious professional grade communications receivers. To see technical info on these receivers, click the photos above and below.
An interesting note about the SX-16 above: In the mid 1930s, it was learned that Germany's fleet of air ship dirigibles were being guided through a network of 50+Mhz triangulated ground stations. As fear increased in Great Britain that these ships would eventually be used for bombing raids on England, the U.S. military was called upon to come up with a means for allowing the British defense agency to track the path of dirigibles that could be headed to a target in Great Britain. The U.S. military called on Hallicrafters engineers to produce a receiver that could tune to frequencies up to 62Mhz. Prior to that request, short wave receivers were limited to frequencies below 30Mhz. The success of the SX-16, and the ability of Halligan's company to quickly custom craft receivers for special and unique applications, resulted in Hallicrafters becoming the U.S. Military's 'go-to' for specialized communications throughout WW-II.
The Hallicrafters SX-24 and SX-25 "Skyrider Defiant" receivers were examples of highly respected Hallicrafters commercial grade radios that were manufactured in the Depression years leading up to World War II. By the beginning of the War, the SX-28 had evolved, from the successful line of SX models, to become Hallicrafters' and the Army's premier wartime receiver.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)
Hallicrafters S-20R "Sky Champion" all band receiver.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)
Similar in appearance to the popular S-20R above, the S-22R was a series string filament set designed for AC-DC and specifically marine use. (click photo for manual).
The SX-28, shown here with matching external speaker, was Hallicrafters most revered receiver. This model saw extensive use in WW-II as the matching receiver to the BC-610 military communications unit.
At left, Hallicrafters' Echophone GI Radio advertising material from the World War II era. At right is a depiction of Hallicrafters founder William J. Halligan (seated). On the credenza behind Halligan's chair is what became known as the Cadillac of short wave receivers. The Hallicrafters SX-28, as illustrated in this Hallicrafters PR piece, has found it's way into the Museum Of Yesterday's Hallicrafters radio collection. The SX-28 became the standard receiver for use by the U.S. Army Signal Corps during World War II, and it was sold as a companion receiver to the HT-4 / BC-610 truck mounted communications center.

Hallicrafters produced a massive amount of advertising material intended to enhance the experience of operating their products. One such example is this short wave listening calculator designed to assist users in determining the best listening times for specific international broadcasts.

An excellent book which covers the history of Hallicrafters, is now available for free download from American Radio History.
Click here . to download a PDF copy courtesy of the author.

Nearing what they knew would be the the final days of the Hallicrafters Company, Halligan's company produced a sales inducing demo recording, featuring narration by popular news commentator Alex Dreier, designed to illustrate the excitement that could be realized by owning a Hallicrafters short wave receiver. A rare copy of this recording exists in the Muerum Of Yesterday library.


Although Halligan's company had distinguished itself even before the United States became involved in World War II, the Hallicrafters name became synonymous with communications radio, during the War, mainly because of the Military-Industrial cooperation that developed the late 1930s. One such cooperative project, which involved a group of ham radio operators, Hallicrafters company engineers, and military officials, took the company's highly successful HT-4 ham transmitter, and modified it for rugged service required for use in the European theater of WW-II. The truck-mounted BC-610 communications van, as it became known, was the Army's single most durable radio transmitter of the era.


The military version of the Hallicrafters HT-4, carrying the military designation of BC-610. (click photo for service info)

You are welcome to download this rare vintage WW-II era film featuring the manufacture of Hallicrafters' equipment including the BC-610.

Inside view of a WW-II SCR-399 communications van that was designed by Hallicrafters for the Signal Corps.

The Hallicrafters SX-42 receiver was the post-war top-of-the-line from the Hallicrafters Company of Chicago.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

From the same post war era, Hallicrafters also introduced the SX-43 receiver, which was a smaller version of the popular SX-42.
After many years of searching, the museum was recently able to locate a mint condition Hallicrafters SX-62 receiver from a nearby owner in Virginia. The SX-62 was a 1950s update on the popular classic post-war era SX-42 model. The newer set had many of the same features, quality of construction, and sensitivity as the rock-stable SX-42, but with a more modern sleek appearance, and an easy to read slide-rule dial. Another significant improvement of the SX-62 over the earlier SX-42, was the addition of coverage for the six meter ham band and the 88-108 Mc. commercial FM band.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)
The Hallicrafters S-86 was one of the company's 1954-1957 era sets made with economy in mind. It used a series filament string, half-wave rectifier, and ballast to avoid the added expense of a full wave power supply and power transformer. To view the manual and circuit diagram, click the photo above.
The Hallicrafters model SX-71 was first introduced in 1949, and was specifically for ham bands through 6 meters. There were three model runs of this receiver, the last having a black face dial as shown above. For technical info on this receiver, click the photo above.
Hallicrafters S-38 receiver
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)
Hallicrafters Model S-53 AM-Short Wave receiver.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

An extremely rare Hallicrafters HT-110 marine radio-telephone
Because of Bill Halligan's personal involvement in the Ham radio hobby, Hallicrafters Company was extremely in touch with the needs of ham radio operators. It was not unheard of for the company to make slight improvements to a particular model while it was still in production. One such case is the S-40 receiver. The two photos below illustrate the slight differences between the S-40A and the later S-40B which corrected some of the slight deficiencies of the earlier model. The later model S-70 also bears striking resemblance to the S-40 series although it utilized more modern tubes and circuit design.
Above, the museum's Hallicrafters Model S-40A receiver is similar in appearance to the later Model 40B which is also in our collection.

The Hallicrafters Model S-40B was an improved version of the S-40A receiver was patterned after the high end SX-42, but with a substantially lower price tag.

Throughout the entire manufacturing run of Hallicrafters' communications equipment, the "SX" series indicated the top-of-the line offerings, while the "S" series was a more budget conscious SWL grade radio. The Hallicrafters Company also built a line of transmitters for amateur, commercial and marine use. The company's transmitter line carried the model designations beginning with the letters"HT."

(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

Not technically advertised as a "Ham" radio, the 1956-57 Hallicrafters S-102 was an economical AC-DC "series string" VHF radio that could be used for monitoring the two-meter amateur band, as well as certain Civil Defense and Military Amateur Radio Service (MARS) transmissions. While it presented a low cost option as a monitor, it's limitations as an AM only receiver made it obsolete once traffic in the 140-150 Mhz range switched to the more efficient FM mode. (click photo for service info)
In the years after WW-II, and all through the 1950s, Hallicrafters had great success with the release of some of the company's most revered radios and even televisions. Toward the end of the 1940s, Hallicrafters was one of the first companies to build home television receivers. An example of a primitive 7 inch Hallicrafters TV, made at a time when Channel 1 was still included in the VHF-TV band, is on display at the museum, and can be seen on another gallery page in communications section of the collection. After 30 years of successful sales, the 1960s brought greater competition from the "assemble it yourself" kit radio market. Also, the introduction and popularity of FM and Single Side Band into the ham radio hobby, presented manufacturers with an ever increasing demand for new designs of equipment. The strains of rapidly evolving new technologies that were placed on established manufacturers forced many companies out of business.

The Hallicrafters SX-140 was one of the later receivers manufactured just prior to the demise of the company. It was a ham band exclusive receiver with more modern styling that was competitive with the later sets made by National Radio Company, Heathkit and Allied Radio, three of Hallicrafters' biggest competitors in the early 1960s. Interestingly enough, this set was also offered in kit form using the name HALLI-KITS. This was an unprecedented move by Halligan's company, and it serves as evidence that the Hallicrafters Company was being forced to respond to heavy competition from Heathkit and Allied Radio. A few years later, in 1966, the Halligan family sold the company, which had by then become mainly a subcontractor to Chicago Musical Instruments in the manufacture of Lowrey electronic organs. Under the new ownership following the 1966 exit of Halligan, radio manufacturing ceased and the Hallicrafters name became just another piece of communications history. (Note that by clicking the photo above, you can see the original manual and kit assembly instructions for this radio.)

The SX-140 is a radio of particular interest here at the Museum of Yesterday because, as evidenced by the photo on page 1 of the communications equipment section, it was the receiver used at our founder's station K5HTZ in New Orleans during his high school years. The station consisted of an SX-140, a Knight-Kit T-60 transmitter, and a Knight V-44 VFO. While the original station is long gone, and the home in which it was located, was demolished as a result of Hurricane Katrina in 2005, an authentic replica of the ham shack, including the station equipment, is now on display at the Museum of Yesterday.

The Hallicrafters HT-40 75 watt Phone/CW transmitter was the companion unit to the SX-140 receiver.
This Hallicrafters Model HA-1 keyer was one of the accessories offered for the later line of the company's ham radio products.
Note: The owner's manual is available by clicking the photo above.


Hallicrafters introduced a number of external speaker styles over the years. In some cases, the speakers were designed with unusual impedances in order to match the audio output of specific receivers. Here are a few of the speakers in the museum's Hallicrafters collection.
The RT-12-T with 2500 Ohm impedance. One of Hallicrafters' earlier external speakers, it was first introduced in the mid 1930s as the companion to the SX-16 receiver. Unlike later types of speakers made by the company, that were all metal, the RT-12 has a wood panel that forms the front of the otherwise metal housing.
The PM-23 speaker was offered as the companion to the SX-28 receiver. Pre-war versions had a chrome letter "h" in the lower right corner of the grill, however, it is believed it was eliminated, as a cost-cutting measure, in later models made for military use during WW-II

The R-42 Reproducer was designed as the companion to the post WW-II SX-42 receiver.

This speaker was marketed as a High Fidelity reproducer with Bass Reflex design features. The SX-42 touted a high fidelity audio system utilizing push-pull 6V6 audio output tubes. The concept of high fidelity sound reproduction was new to the post-war era, and the R-42 included not only a totally enclosed and insulated baffle cabinet, but also a 12" extended range PM speaker with an extremely large magnet.

Hallicrafters R-46B speaker which is the companion speaker for the SX-62 series. A similar model R-46 replaced the brushed metal grill with a painted grill of similar design design.
The model R-48, shown above, was one of the later speakers offered to match the SX-140 receiver.
The R-47 compact speaker was one of the later offerings to match 1960s era radios.
Sold in the 1960s as a match to the SX-122 receiver, this Hallicrafters R-50 speaker is one of the last external speakers offered by Hallicrafters at a time when the company was winding down production. While Hallicrafters products of this era are still valued by collectors, there is an obvious lack of attention to quality over the speakers offered by the company in the 1930s and 40s.

A manufacturer's service manual is available on the above receiver. Click image above to open PDF file.

The Hammarlund HQ-1290X was a popular ham and communications receiver when it was introduced in late 1945. After a long search, the museum is proud to have this excellent example of a Post War HQ-129X in our collection. The HQ-129X was an improved version of the company's HQ-120X, which was a popular pre-World War II product. The new HQ-129X boasted several improvements over the previous set when it first appeared in an ad in the November, 1945 edition of Radio News Magazine. That ad appears below.

Matching speaker for the Hammarlund HQ-129X
Hammarlund HQ-140-X general communications receiver was one of many pre and post WW-II receivers built by the Oscar Hammarlund Co. of New York. Shown are front view (above) and interior view (below) This was a very high-end receiver in its era.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

This is the Hammarlund HQ-170A. It was one of the last Hammarlund models to maintain the basic panel layout that originated with the Super-Pro in the 1930s. Although the 170A was designed around post-war miniature tubes, it was one of the last high end communications receivers to still utilize hand wired point-to-point circuitry.
This item was donated to the museum by Armand Hammel,
Like Hallicrafters, National, and a number of kit receiver manufacturers, Hammarlund supplied matching external speakers for their speakerless models. This Hammarlund S-200 speaker was intended to match receivers in the HQ-100 through the HQ-170 series.

The museum recently acquired this classic 1949 Harvey-Wells "Bandmaster" transmitter. It has undergone full restoration in our shops and is now on display in our ham and short wave communications gallery. This transmitter was very popular with ham radio operators in the early years after WW-II because of it's phone/cw features and reasonable price tag. Improvements were made to the "Bandmaster" in the post-war years, and model numbers, ranging from "A" through "D" indicate into which generation the set falls.

Harvey-Wells produced economical transceivers and transmitters for amateur and commercial use. Some of their most popular offerings were the "Bandmaster" transceivers of the late forties. The company was founded as "Harvey Radio Labs" by Clifford A. Harvey in 1933. Shortly thereafter, Dick Mahler joined the Company. The "Harvey Radio Labs" produced HF, VHF and UHF transceivers and transmitters as a low budget concurrent to Collins Radio Corp. Their equipment has been used by hams and commercial enterprises. In 1940 John Wells joined the company, the name was changed to "Harvey - Wells Electronics Company" in march 1940. They produced equipment used for police communication, civil defense and the Navy.

After the war, within a range of ham band transceivers, Harvey - Wells produced the TBS-50 "Bandmaster". The company didn't make the step to single sideband transmitting technique and numbers of sets sold dropped. In 1957, the company was acquired by "Within Machine Works." The "Harvey Radio Labs" company still existed and became owner of broadcasting stations.

(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

Below are two views of the inside of the TBS50D

Founded as an aircraft company in 1911, Heath Company of Benton Harbor, Michigan began offering electronic equipment in kit form in early 1948. Shortly after World War II, the company purchased a large stock of surplus parts acquired through the U.S. War Assets Administration, a temporary government agency charged with disposing of excess material from the war, with the intent of selling "do-it-yourself" radio kits at substantial savings over factory made items.

Heathkit's first ad for a product appeared in March of 1948 when they introduced the Model K-1 which is a receiver shown below. Heathkit soon became the "go-to" supplier for many hobbyist and ham radio customers, which continued over the life of the company. Originally a strictly mail order operation, the company eventually opened franchised stores in many locations around the country. Their product line included ham radio products, audio equipment, test instruments, computers, color televisions and electronic organs, all in kit form. Having undergone later mergers with first Daystrom and then Zenith, and facing competition from over-seas manufacturers and an ever increasing difficulty in product construction due to advancing technology, the company ended retail sales in 1992.
Heathkit's first kit radio offering, introduced in March of 1948, was the model K-1 all wave radio kit. Designed as an inexpensive hobbyist project, the AC operated K-1 and battery K-2 version were introduced at a cost of $8.75 without case or speaker. The speaker was offered separately for $1.95, and the wood cabinet first became available in the company's 1949 catalog.
Rear view of the Heathkit K-1 120 Volt AC All Wave Radio

The general consensus at the time is that the K-1 was intended to be HeathKit's competitive offering against Allied Radio's popular Knight-Kit "Ocean Hopper" receiver, which had been around since the late 1930s, and which was substantially upgraded and heavily marketed after the war ended. Unlike the "Ocean Hopper," which was a "hot chassis" set that supported headphone listening only, the K-1 featured a safe AC transformer type power supply, and offered an optional 2-1/2" speaker for an additional $1.95.
The Heathkit AT-1 CW transmitter was the Benton Harbor, Michigan company's first entry into the amateur radio market.
To see a copy of the assembly manual for the Heathkit AT-1, Click the photo above.

The Heathkit DX-20 50 watt CW transmitter was designed around a final amplifier tube originally intended for service as a horizontal sweep amplifier in television receivers. The relatively low price and easy assembly of the DX-20 made it a popular CW transmitter in its day for newly licensed "Novice" class hams on a budget. The photo below shows the museum's DX-20 powering a 100 watt dummy load lamp.

(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

Similar in appearance to the DX-20 above is the DX-40, which is a phone/cw version of Heathkit's basic CW transmitter. The DX-40 circuitry replaced the DX-20's 6DQ6 final amplifier with a more rugged 6146 tube, and it included a screen grid modulator section to allow phone operation. Both transmitters still required crystals or an external VFO such as the VF-1 shown below. The museum owns examples of both the DX-20 and the DX-40. Our restored DX-40 is pictured below. Technical info can be obtained by clicking the photo.
The Heathkit VF-1 was a popular companion piece to Heathkit's novice class crystal controlled DX and AT-1 series transmitters. The unit employs a single 6AU6 vacuum tube as the oscillator. Note that the 11 meter option still existed at the time that this unit was made. Later, 11 meters was reassigned as Citizen's Band radio and was no longer available as a ham radio band. Click the photo above for a downloadable copy of the assembly manual for the VF-1.

Heathkit DX-100B 120 Watt phone and CW transmitter from the late 1950s

The Heathkit DX-100 was probably one of the finest pieces of ham radio gear that the company offered. A few of these transmitters can still be found in service seventy years after they were first introduced. Conservatively rated at 120 watts phone/cw, and boasting full plate modulation of the dual 6146 final amplifier, it out performed the Knight-Kit T-150 and other screen grid modulated rigs having 6146 finals.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

The Heathkit "TWOER," often referred to as the "Benton Harbor Lunch Box," was one of a series of portable tube VHF transceivers made in the heyday of the Heathkit company. The "Twoer," the "Sixer" and a ten meter version were available. The "Twoer" found additional use as a communications instrument for Civil Defense, Civil Air Patrol, MARS and other para-military and rescue services. (This item was donated to the museum by Jim Lewis-W8MGZ)
Many 1950s hams, who built their rigs around the Heathkit brand, will also remember this model AM-2 SWR meter.
Heathkit Grid Dip Meter.
Grid dip meters were used to determine resonance of coils and tuned circuits prior to the introduction of computerized test equipment.
Analog phone patch Model HD-15, a ham radio accessory from the Heathkit Company.

(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

One of the last generation of Heathkit "Ham" radio products was this late 1970s HW-99 CW only transceiver.

While Heathkit enjoyed a stellar reputation for their post-war through 1960s product offerings, the mid to late 1970s saw a sharp drop-off in the quality of their equipment. In an attempt to keep up with modern and more complex digital transmitters and receivers for the Ham market, shortcomings were found in their later designs such as the frequency instability for which HW-99 was notorious, and many kits had became complex to the point where average customers could not successfully assemble them. . In addition, the company undertook an ambitious plan to open local sales and service stores for their products in the 1970s, as a way to boost their slumping mail order sales. Many believe that this huge undertaking contributed to their demise. By the late 1970s, most customers knew that the company's days were numbered, and the influx of already assembled and tested amateur radio equipment from Japan and the Far East, eventually sealed the fate of the Benton Harbor, Michigan based electronics pioneer.

The Heathkit HO-10 monitor scope was popular in the '60s era when Single Side Band was replacing AM as the preferred mode of ham voice transmission.


The Howard Model 437-A multi-band receiver was another inexpensive communications radio from the 1930s. There is some obvious similarity between the case style of this radio and some of the earlier Hallicrafters and Echophone sets. This had to do with the connections between Hallicrafters, Echophone and Howard in the years when Hallicrafters did not possess an RCA license for manufacturing their products. Popular belief is that Howard may have made some of the radios sold under the Hallicrafters and Echophone names in the early Depression years.

Howard Radio continued in business through and after World War -II. The company failed to make the transition to the miniature tube and transistor era and they faded from the scene by 1949. (Click image above for service information)

Johnson Viking Model 122 external Variable Frequency Oscillator

E. F. Johnson 6 and 2 Meter VFO
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

The Johnson Viking Ranger CW-AM Transmitter
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)
A Johnson Viking Matchbox antenna tuner was a high-end accessory to round out any Johnson equipped ham shack.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)
Knight Kit electronic kits by Allied Radio Corporation, Chicago, IL
As part of its 1950s line of hobbyist radio and electronics kits, Allied Radio offered three super-regenerative "beginner's" AM/Short Wave radio kits. The three-tube "Ocean Hopper", which took its name of an earlier Allied kit from the pre-WW-II era, was the first miniature tube type kit offered after the War. Band changes were accomplished with plug-in coils which were inserted through a trap door in the top of the cabinet. The "Ocean Hopper" also required the use of headphones for listening. A few years thereafter, Allied introduced the "Space Spanner" which employed basically the same regenerative circuitry as the "Ocean Hopper," however this set had provisions for a loud speaker, and band switching coils were permanently wired onto the chassis and employed a four-position band switch. By the late 1950s, changing styles, and safety concerns emerging from the "hot chassis" design of the "Ocean Hopper" and "Space Spanner" prompted Allied to release the "Span Master." The "Span Master" utilized the latest vacuum tube technology with two tube sections sharing a common glass envelope. The set also employed a power transformer which served to isolate the set's internal wiring from the chassis, thereby eliminating the shock hazard posed by "hot chassis" sets. All three of these Knight Kit sets are in the museum's collection and can be seen below.
The three tube The Knight-Kit "Ocean Hopper"AC/DC AM/Short Wave radio of the post War era.
The three-tube Knight-Kit "Space Spanner" from Allied Radio Corporation was a later "mid-range" regenerative hobby receiver.
The "Span Master" was a later upgraded regenerative tube-type receiver kit offered by Allied. This one dates to 1958.

Allied Radio and Heathkit developed a unique step-by-step assembly procedure for building their products in kit form. To see an example of the assembly manual from a Knight-Kit Span Master radio, click the icon below.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)


The Knight-Kit R-100 receiver

With increased interest in amateur radio by a generation of post WW-II baby boomers who were now coming of age, 1957 proved an opportunity for Allied Radio to address mounting competition from Heathkit, Hallicrafters, and other manufacturers of serious amateur radio equipment. Previously, most of Allied's Knight-Kit short wave receiver offerings were limited to basic regenerative type "experimenter" kits such as the popular "Ocean Hopper" and "Space Spanner." With the introduction of the R-100 receiver, Allied launched into the production of serious short wave and ham radio equipment that was intended to compete directly with Heathkit. This progression of higher end receiver and transmitter kits continued through the 1960s.

Catalog page from the 1958 Allied Radio Corporation catalog introducing the new line of ham equipment including the R-100 receiver.
After World War II, Allied Radio accelerated their development of kit form equipment in competition to the successful Heathkit line. In addition to improved versions of the Ocean Hopper and Space Spanner receivers, Allied answered the demand for an inexpensive HAM CW transmitter. Their first offering in the transmitter market was the T-50. Very similar in appearance and operation to the Heathkit AT-1, the Knight transmitter utilized a 6AG7 oscillator, type 807 final and a 5U4G rectifier. The 807 provided slightly more output than the Heathkit offering which used a 6L6 as the output tube. Allied Radio anticipated that this would make the T-50 a more popular transmitter than the slightly lower power unit offered by Heathkit.

See the complete assembly and instruction manual for the Knight T-50 by clicking the photo above

The Knight-Kit T-60 60 watt AM/CW transmitter
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

After several years of sales of the popular T-50, Allied needed a small AM -CW transmitter to compete with Heathkit's disappointing DX-40 and then the more popular DX-60 transmitters. The Knight T-60 was a sleek screen grid modulated AM rig which used a 6DQ6, originally developed for use as a TV horizontal sweep amplifier, as it's final amp. As seen in a photo on the home page of the communications collection, The Knight T-60 was the transmitter used by Mr. DeMajo at the original K5HTZ station in New Orleans during the early 1960s.

Another popular Allied Radio kit for the ham operator was the Knight-Kit V-44 VFO. For many hams, it provided an economical companion to Allied's Knight T-50 and T-60 transmitters. Upon upgrading to General Class license, a budget minded ham could acquire a V-44 for a mere $29.95, (the 1960 listed catalog price) thereby allowing the T-50 and T-60 transmitters to shed their previously "rock-bound" status. (Click the photo above to see the manufacturer's assembly manual)

(Additional info available...Click photo)

Allied Radio's last major entry into the Ham market was this T-150 transmitter. Obviously designed to compete with the popular Heathkit DX-100, the T-150 also featured built-in VFO frequency control and a 150 watt final amplifier employing two 6146 tubes. Unlike the DX-100, however, the T-150 used screen grid modulation instead of more expensive plate modulation that was standard on the Heathkit transmitter, and there were inherent design problems with the built-in VFO, which was known to cause spurious signals..

While the company continued to offer the matching receiver and several other ham kits as late as the 1970 model year, at which time the company was sold to TANDY Corporation, The T-150's run was short-lived, and it was last offered in Allied's 1965 general catalog.

The Meissner Deluxe Signal Shifter was a self contained low power VFO transmitter-exciter.
(Manual available, click photo)

National SW-3 was a popular basic and affordable 3 tube communications receiver first introduced in the mid 1920s.
With their popularity and simple performance for that era, the SW series receivers were dubbed "Thrill Box" radios.

(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

Above: an ad for the National SW-3 "Thrill Box from an early 1930s supply house catalog.
The $17.70 price tag from 1930 would equate to approximately $275.00 in 2020 dollar value.


National HRO Communications Receiver with Type "G" Coil Assembly and matching speaker.

The HRO dial was a device patented by National Corporation. See a copy of the patent application here- .
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

The early HRO receivers required additional "plug-in" coil assemblies for band changing. Pictured is a set of HRO coils, in their factory supplied rack holders, intended for use with the receiver above.


Above: 1948 National NC-240DT communications receiver with speaker.
Below: 1941 National NC-44 receiver.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

See ad below from 1941 Amateur Radio Handbook covering these two receivers.

The National NC-300 was another top-of-the-line receiver in its day
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

The National SW-54 was a basic SWL (short wave listener's) receiver built with the look and feel of National's higher end "Ham" and commercial communications grade receivers.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

The NC-57 was a post-War receiver intended for the ham and SWL market, but with a more reasonable price tag than the NC-200 and NC-300 class receivers. It was priced to compete with the popular Hallicrafters S-40A and B sets. Click the photo above to see the manufacturer's manual on this set. To follow a detailed documentary on the restoration of this set, click here
In addition to manufacturing a popular line of receivers over the years, National Radio was also one of the most prolific makers of components for the construction of transmitting equipment. Many Hams utilized National's components in their "home brew" projects, and the military relied heavily on National for war-time component supply. The animated 1947 catalog below illustrates the variety of products offered.

This RME 152A "Frequency Expander" was a recent gift to the Museum Of Yesterday from Ham operator Jim Lewis, W8MGZ RME was a company based in Peoria, IL that manufactured communications equipment. This unit permitted reception of VHF bands on a standard short wave receiver. (click image to view for manual)

In 1931-32 Radio Manufacturing Engineers was founded by E.G. Shalkhauser (W9CI) and Russ M. Planck (W9RGH), they started producing their first receiver RME-9 in 1932. In 1943 the company moved to 313-315 Bradley Ave and in 1935 to 306 First Ave., Peoria, Ill.,where the company's most famous set, the RME-69 was produced. After the War, RME merged with Electro-Voice, Buchanan, Michigan; Planck stayed with the company and supervised the design of a new series of short wave receivers under the name of Radio Mfg. Engineers, Div. of Electro-Voice Inc. In 1962 RME Division was been taken over by G. C. Electronics of Rockford, Ill., the name of RME disappeared within a year. (Excerpt from



This 1939 vintage 20 Watt CW transmitter, manufactured by the Thordarson Transformer Company, utilizes a 6L6-G as the RF oscillator/RF output tube, along with a Type 80 full-wave rectifier. Following full restoration, the unit was recently placed on the air for a demonstration, and it still kicks out a mean little signal for it's size.

Click the icon above to view the original 1940 manufacturer's catalog cut for this product

The World Radio Laboratories "Globe Scout"

The art and science of Ham radio was an outgrowth of interest in the new field of electrical engineering. While scientists and researchers were discovering new applications for electricity in those early years of the 20th Century, many amateur experimenters were following the same path in their own garages and basements. Many of the advancements made in radio, throughout the years, were the result of discoveries made by amateur scientists and experimenters.

For the first half of the century, a great deal of ham radio equipment had to be built by the amateurs themselves. Books from that era featured construction articles, diagrams, and workshop practice suggestions mainly aimed at amateur operators who wanted or needed to build their own radios.

This section of the site is set aside for the display of home-made radios and equipment which have found their way into the collection of the Museum Of Yesterday.


In 1935, a group called "The Editors Of Radio" began publication of an annual book of their assembled notes and projects of interest to radio experimenters and amateur radio operators. The publication, entitled "Radio Handbook" was more than likely intended to compete with the ARRL's popular "Radio Amateur's Handbook" which followed the identical basic format. By the time of the release of the Seventh Edition in 1940, the Radio Handbook had become a well accepted guide for experimenters and engineers alike.

The 1940 edition, and possibly previous editions going back to at least 1938 as well, featured a simple two-tube regenerative receiver project which could be constructed on a wood base with a metal front panel. Recently, the museum's acquisitions staff came across such a radio, in an auction, which had obviously been constructed based on that same Radio Handbook article.

Fortunately, we were able to obtain the set, and it is now undergoing full restoration for inclusion in our permanent collection. Shown below are front and rear photos of the receiver as it began the restoration process in the museum's radio shop. By clicking the button directly below, the viewer can also obtain a PDF copy of the referenced original article as it appeared in Volume Seven (1940) of the "Radio Handbook."


(Above and below:) The two-tube regenerative "ham" radio receiver which is believed to have been constructed from an article in the 1940 release of "Radio Handbook."
This is an example of an early 1920s style amateur radio receiver that was built from an ARRL Radio Amateur's Handbook article using authentic components of the era. While this one piece from our collection is not an authentic "antique," it is an example of excellent reproduction work by one of a number of hobbyists who collect original 1920s parts in order to build equipment that lets us experience what early ham radio operators had to deal with in the infancy of radio.

A homebrew 6L6 novice transmitter from the 1950s. The bottom deck of this rig is typical of many "first rigs" that young hams on a budget built from recycled radio and TV parts in order to get on the air after receiving their Novice ticket. The television set power transformer and 5U4GB rectifier tube were likely provided, as an incentive to the young ham who assembled this rig, courtesy of the old set scrap heap at a neighborhood "mom 'n pop" radio and tv repair shop. On the lower deck, the device behind the 6L6 is actually a WW-II military radio crystal in a hermetically sealed 8 pin container that resembles an octal metal tube. The top deck was probably added in order to turn the formerly CW only transmitter into an AM/CW rig. Many novices who couldn't afford new equipment, either built AM modulators for their CW rigs, or used modified Hi-Fi amplifiers as modulators when they upgraded to General.

One manufacturer, Eico, offered a factory built modulator that was essentially a Push-Pull Hi-Fi amplifier with a modulation transformer in place of a standard output transformer. It was intended as an accessory for their novice transmitter, and could also be used with the Heathkit AT-1, DX-20, or the Knight-Kit T-50, which were all entry level CW only transmitters.

The unit above is a 20 watt 6J5 (oscillator) 6L6G (final amp) crystal controlled CW transmitter intended for novice band use on 80 and 40 meters. It dates to around 1935. Note that it uses the older type Bliley circular crystals which were popular prior to WW-II. During and after the war, the smaller dual pin crystals were used in most new equipment designed for Amateur radio use.

Shown above: An early 1950s VHF transmitter.

While amateur radio experimenters had become interested in VHF and UHF frequency operations prior to WW-II, it was actually wartime developments, mainly in the realm of RADAR, that perfected the tubes and hardware needed to successfully operate in the VHF and UHF spectrum. By the early 1950s, ham operators were successfully harnessing the 6 and 2 meter bands for short-range AM communications. Not long after, it was found that FM was superior in these regions, and that opened the door to repeater and portable devices that are still being expanded and refined upon with today's available technology. Pictured above is a typical VHF transmitter from the early 1950s. Tubes which were still somewhat strange to amateur radio, such as the 829 shown in the final amplifier cavity above, became the new tools for operators who wanted to venture into this new territory.


by John DeMajo, museum founder

Back in the days long before the era of foreign manufactured all-band desktop transceivers, every ham dreamed of owning that monster transmitter that could dim the streetlights while radiating enough RF to talk to anyone, anywhere. In the Depression and pre-war years, manufactured transmitters were scarce and expensive, so many Hams built their own transmitters. Radio publications from that era contained a full variety of amateur radio projects that ranged from simple one-tube receivers to mega transmitters that rivaled commercial radio broadcast station equipment. A Ham's success in assembling such equipment, was testimonial to both the mechanical and electrical proficiency of the builder.
Some time ago, the museum came into possession of a large collection of ARRL and other ham radio publications from the era of 1929 through 1960. We decided to see what a pre-WW-II Ham would have experienced in trying to build a large transmitter from the period of about 1938. The Radio Handbook of that year featured a phone/CW transmitter rated at 250 watts, that seemed appropriate for the project. After combing the surplus markets at hamfests and on EBAY, for eighty-year-old parts that were still functioning, we were able to assemble such a transmitter using authentic 1938 vintage parts and construction practices. The following section documents this project with photos and diagrams of that transmitter which now resides in the museum's collection in Virginia.


The transmitter is built in a 19" x 48" BUD rack. The four bays are: (from bottom) the high voltage power supply and line power control section; the 125 watt P-P 807 modulator and speech amplifier deck which also holds the medium voltage power supply for the modulator as well as the power supply components for the oscillator and buffer sections of the RF unit; the RF deck which contains the crystal oscillator, buffer and dual 811 finals; and the top deck is the Pi network type antenna matching unit.


In the late 1930s, the Depression was easing and many serious ham operators were able to purchase commercially built receivers. Transmitters, however, were less plentiful and considerably more expensive. In that era, many hams typically built their own transmitters using laboratory tested designs that were featured in ARRL handbooks and other ham publications. This "pristine" rack mounted 250 Watt CW transmitter-exciter, utilizing a 6A8 oscillator tube, along with a 6L6 buffer and dual 811 finals, was an example of a professional quality well constructed rig from that pre-World War II era.. Below is a rear chassis photo showing the internal construction of the RF unit.

Rear view or the transmitter's RF deck
Above: Schematic of P-P 807 modulator.
Under chassis view of the wiring for the push-pull 807 modulator section.
Below: A photo from the original 1938 Radio Handbook showing the suggested design of the power supply deck, along with a photo of the power supply constructed for our project.
Another article from the 1938 edition of Radio Handbook illustrates the status of VHF communications in that pre-WW-II era. At the time, use of frequencies above 30 Mhz, was virtually uncharted territory for amateur radio operators and commercial entities alike. It was not until the years leading to World War II, and the on-going research for sophisticated military applications such as Radar and Microwave transmission, that tubes and components capable of easily handling these higher frequencies, were developed. By 1936, however, hams recognized the potential for these new VHF and UHF spectra. The 1938 Cairo Convention further expedited this as it removed the 40 meter band from the Amateur spectrum, and replaced it with 2-1/2 and 1-1/4 meters. The following exhibit and accompanying Radio Handbook article illustrate how early VHF experimentation had already begun.

A working model of the oscillator, described in the 1938 Radio Handbook, is on display at the museum.
For four decades, ham radio operators were entertained by the "Jeeves" cartoons as penned by ARRL artist "Gil" (Phil Gildersleeve - W1CJD). The fictitious Jeeves, who was the butler to a Ham, routinely demonstrated who was actually carrying the load of the household association. Over the 40 years of his association with the ARRL, thousands of Jeeves cartoons appeared in QST and other ARRL publications. "Gil" was also editor of the Middletown Press, but most famous for the cartoons he penned over the years for the ARRL. Gildersleeve became a "Silent Key" in 1966.
NOTE: Manufacturers' literature and other reproduced technical information available on this web site are made available under the Fair Use Doctrine of the U.S. Copyright Laws. Material is displayed for educational and historical research purposes only, and is not available for sale or otherwise distributed for profit.
Copyright 2020, The Museum Of Yesterday, Chesterfield, VA USA