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The Crosley Radio Gallery



You are in Gallery 6 of the Communications Collection...Please continue on your tour.

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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 encouragement of Hiram P. Maxim, as a fraternity of amateur radio operators in the early days of experimental radio at the beginning of the 20th Century. A century later, the League has grown to membership approaching two-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 educational publications have documented the development of radio over the course of the 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.

The Museum of Yesterday is proud of our Life Member status that dates back to 1959 when our founder Mr. DeMajo, as a young teenager, joined the League upon receiving his Novice Class FCC radio license. Below, a recent photo of our founder and chairman, who now holds the most advanced classification of ham radio licenses (Extra Class), at the controls of the Hiram Percy Maxim Memorial Radio Station "W1AW" at ARRL headquarters in Newington, CT, in celebration of the 55th anniversary of the issuance of radio call sign K5HTZ. .

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.

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. Of course things were simpler from a technical and financial standpoint. Single Sideband, Packet, FM and UHF were just things being talked about. For the average young ham, 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 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 budding amateur radio operators. Many of today's seasoned Hams, got their start with home-made transmitters that used tubes such as 6L6, 807s and such. A great deal of the rewards of the hobby came with the satisfaction of building your 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 that equates to a college trained engineer or professional technician. On the other hand, many Hams are again discovering that same satisfaction through kit built radios, devices such as the Raspberry Pi, and so forth. Remember 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.

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 operators had available to them in the mid-20th Century.
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).

Despite numerous attempts over the years, the museum was only recently successful in obtaining this mint condition Ameco AC-1 Novice class CW transmitter for our permanent collection. The transmitter, which represented a "bare bones" rig for budget strapped Novice class operators during the late 1950s, sold for around $15 (in kit form) at the time. The AC-1 was highly advertised in radio magazines during that era, and because of their apparent nostalgic significance to the golden era of ham radio, today remaining units, in unmodified condition, are selling for upwards of $300 whenever they become available.

Today, 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. Like a few other relics of the great era of radio development, the AC-1 now enjoys the same kind of skewed price value as the Zenith Walton radio, Atwater-Kent breadboard radios, and other iconic pieces of our past.


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
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.
This device was popular with "mobile" hams on a budget
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..
(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.


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.)

Advertising material from the World War II era. At right is a depiction of Hallicrafters founder William J. Halligan (seated).

The Museum Of Yesterday recently acquired this Hallicrafters SX-24 "Skyrider Defiant" receiver. This radio was the epitome of short wave receivers in the years leading up to World War II.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

Shown below is the Hallicrafters PM-25 which was the matching speaker for most pre-WW-II Hallicrafters receivers. It contains a 12" Jensen permanent magnet type speaker and a transformer to match the 500 ohm audio output found on most of the early Hallicrafters sets from this era.


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.)

Shown below is the Hallicrafters R-46B speaker which is the companion speaker for the SX-42 series. It was released following World War-II, along with the company's line of early post-war receivers.

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.
Hallicrafters S-38B 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.)

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 Allocates' 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 Allocates 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.)

Hallicrafters Sky Champion all band receiver.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)


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 HT-4 ham radio transmitter into the BC-610, 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.

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


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.

Shown above, along with the R-47 speaker, 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.


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

The Hammerlund 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.

Hammerlund HQ-140-X general communications receiver was one of many pre and post WW-II receivers built by the Oscar Hammerlund 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.)


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

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.

(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 reguired 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 Cituzen'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
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)
Many 1950s hams, who built their rigs around the Heathkit brand, will also remember this model AM-2 SWR meter.
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 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.)

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, designed as a TV horizontal sweep tube, as it's final amp.

As shown in the original DeMajo ham shack photo on the home page of the Communications Collection, the Knight T-60 was the first transmitter of Amateur Station K5HTZ. It featured screen grid modulation of a 6DQ6 final amplifier, and allowed for crystal or VFO frequency control.
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 Genral 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 previouly "rock-bound" status. (Click the photo above to see the manufacturer's assembly manual)
National SW-3 was a basic and affordable communications receiver from the early 1930s "Depression era"
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

National HRO Communications Receiver with Type "G" Coil Assembly and matching speaker.
(Manufacturer's manual or additional technical information is available on this item. Click image above to access.)

Above: National NC-200 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

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"

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 Handbok 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 hobbysits 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.
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.
Another popular design for the Ham who was able to "homebrew" a "rig," was this "MOPA" type transmitter employing the popular Type 807 final amplifier tube which became readily available to Hams of that era in the form of surplus from remaining World War-II stock. This design, which is right out of the 1950s ARRL Handbook, uses a 6AG7 master oscillator tube which drives the 807 power amplifier (MOPA). These transmitters were able to kick out a reasonable 50-60 watts on CW, which satisfied most Novice operator requirements, and some hams even went so far as to modulate them for AM operation when they upgraded to General.
NOTE: Manufacturer's 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.
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