The early 1950s were a time of uncertainty in the US.   While the WWII soldiers and sailors had returned home and were re-entering the workforce or using their GI Bill benefits to prepare to do so, the Korean conflict had raised new fears:  the Cold War era was beginning.  While the threat of air raids or invasions in the United States became likely during the war, the focus on the Civil Defense Corps, air raid drills, and patrols of the border declined but other efforts continued.    The Federal Civil Defense Administration (FCDA) was organized by President Harry S. Truman on December 1, 1950, replacing it's predecessor, the Office of Civilian Defense which had been  was abolished in June 1945 with the end of World War II.   The demonstration of an atomic bomb by the Soviet Union in 1949 no doubt had a lot to do with that!

One of the first orders of business was to present a new civil defense to President Truman, a 176 page document known as "the blue book".  It outlined and guided US Civil Defense efforts for many years, and included a statement about the role of amateur radio operators:

AMATEUR RADIO OPERATORS

Amateur radio operators and networks will be used in civil-defense
communications. They are licensed radio operators and their radio-
telephone and continuous-wave equipment can be utilized as secondary
services thus providing for maximum flexibility. Under an organized
plan, amateur radio operators will make an important contribution to
civil-defense communications.

We now enter the realm of speculation..but informed by the above and the status of amateur radio at the time...mid-1952.

Given the emphasis that was being placed on Civil Defense and the heightened awareness of recently returned servicemen to international affairs, it was logical that hams and ham clubs would be drawn to CD efforts.    In fact a cornerstone of the blue book approach was to identify skills and resources in each community and find ways to organize and utilize them in support of the CD activities.   Hams had the knowledge and ability to communicate, which was a valuable commodity, but they lacked a cohesive approach and in many cases the equipment needed to provide reliable local communications.    Thus, the early '50s saw a number of construction articles in QST and CQ aimed at civil defense communications, on 10, 6, and 2 meters.

Of the above, 2 meters was attractive for several reasons.   Modern tubes and technology made it easy to put a usable signal on the air, unencumbered by the disruption of skip and less prone to TVI (especially compared to 6 meters).       That's perhaps why one of the first club emergency radio projects appearing in QST in Oct. 1951, was a 2 meter rig that could be built in several configurations, including a vertically-oriented portable package.

The following year saw a similar rig for 6 meters in an article by W1CTW "A 50 Mc Transmitter-Receiver for Civil Defense Use".  Emphasis was placed on making it easy to use this rig in the field with various power supply and antenna options and it too had a vertical arrangement with a carrying handle on top.  Ham ingenuity was clearly converging on what a low power portable VHF communications set should look like.

And commercial manufacturers were taking note.    There were no one-piece portable rigs on the market at the time, but a company that had built a reputation for making compact mobile gear,  the Gonset Company of Burbank CA was one that saw the need and opportunity.  

The much more obscure Deltronic Corporation, also of Los Angeles, was another.

Very little is known about Deltronic, which produced exactly one product:  The CD-144A 2 meter portable transmitter-receiver.     Most of what we know comes by way of Geore Maier  W1LSB who researched and wrote an article in issue #130 of Electric Radio after acquiring a CD-144.    His quest for additional information came up empty, and only one other owner has been identified until 2023 when I acquired one via eBay.    The history of the company and the CD-144 have all but been lost over the years, but it's logical to think that they were hoping to exploit the Civil Defense opportunity.

The Federal Civil Defense Administration had a budget, but one thing they were not going to spend it on is to subsidize hams to build homebrew radio sets.   A commercial source was needed, and as everyone knows now, the Gonset company filled that need with it's famous Communicators with the special yellow CD paint job and sticker on the side.     It's logical to speculate that Deltronic was hoping for the same plum - even incorporating "CD" into the product name, but that was not to be.

A couple of reasons come to mind.   First is the fact that Gonset was an established company with a balance sheet, employees, and skilled management - things no start-up can claim.   The Communicator was also more radio for the same money - with selectable crystal switching, higher output power, a better receiver (based on Georges findings) and a magic eye tuning indicator that in that era was the mark of a higher-end radio set.   The ability to use common 8 MHz range crystals might have also been a factor.   It would seem that having a handle and whip antenna on top was a prerequisite, but both radios certainly looked the part!

In any event, few Deltronic CD-144s were sold, although they were included in the catalog of at least one distributor, Evans Radio of Concord NH.    The Deltronic manual shows drawing dating from mid-1952 and the Evans catalog was for 1954, so the radio probably came out in 1952.   Gonsets first ad for the Communicator appeared in QST for December 1952 and showed a round speaker grille, which was replaced by an image of the production radio with its rectangular grille a few months later.     The race was on and Gonset clearly won...but were they first?

The CD-144 is a neat little rig, as the photo gallery below will attest.  A 3-tube transmitter and 6-tube receiver are squeezed into a compact chassis only 6" square, a 6AQ5 acts as modulator and audio amplifier for the receiver.  While the W1CTW QST article may have provided inspiration, the CD-144 packs everything, including speaker and power supply, into a cabinet roughly the same saize as the W1CTW transmitter and receiver only.     The power supply and output transformer are mounted on the 2nd (lower) chassis, and here some interesting differences can be noted.    

The W1LSB unit contained an AC/DC power supply using a vibrator for mobile operation what in the early 50s was 6 volts.    A separate winding on the transformer allowed for 110VAC used.    However the unit I acquired has a small transistorized inverter instead,  with a lighter socket plug attached.    A quick test confirmed that this CD-144 was intended for 12 volt operation, as the PNP power transistors on the inverter were not available in the early 50s.   Thus the filaments had to also be rewired for 12 volt operation and of course, 110VAC was sacrificed.    Was this done by the factory ?   Or  by a ham owner?

If the latter, it was someone who had pro-grade skills as the quality of construction is equal to most commercial gear.   For example, the sheet metal support brackets cannot be told from those on the top chassis and even small details, such as precisely located clearance holes for the inverter mounting screws sho no sign of "hackery".    The chassis itself is clearly not repurposed, having no extra holes.     It's unknown how many were made but with a serial number of 198, if the number means anything it would appear to be a "late production model".     12 volts became the automotive industry standard in 1955 and the Deltronic CD-144 was in the 1954 Evans Radio catalog, so it would appear to be possible.

In any case, the radio fired right up from a 12 volt supply, and readily heard an AM test transmission from my FT-817.   Impressive for being built in the Eisenhower administration and sitting unused for who knows how long!    Due to the simplified multiplier chain, the usual 8 MHz crystals can't be used in the CD-144, they need to be in the 18 MHz range.   Fortunately one came with the radio marked "147.8".   Not quite the "AM window" but good enough for a test and sure enough the transmitter put out RF, and by plugging a multimeter into the top-mounted meter jacks I could peak the final and other stages.   Power output was only about 1 watt,  which agrees with W1LSB's experience, and is due to the fact that the final acts as a frequency doubler thus operates at lower efficiency.    Still a usable rig for the intended purpose - the Heathkit Lunchbox that was to come some years later produced similar power but was very popular and widely used, in part because a yagi antenna which provided significant gain could be easily built.    

Modulation sounds good and clear even though the output waveform is a  mess, probably due to the doubling and presence of harmonics.   The receiver noise level goes up whenever anything is connected to the antenna - a good sign.   A 3uV 30% AM modulated signal is easily copied, and a 1uV signal would probably be discernable in a quiet room,  as even with the volume at maximum the audio output is pretty anemic.   But it sounds good and even the dial calibration was not too far off, i.e. within a few hundred kilohertz!     The transistorized inverter does produce a fairly loud and annoying whine all the time, which is probably louder than a vibrator would be.     This is probably a function of the transformer used and nothing can be done about it.    On the plus side, power consumption is a fairly reasonable 5A in transmit or receive.   A rear panel slide switch turns on the ANL.

An oddity:   the carbon microphone actually serves as the cathode resistor for the 5763 final amplifier, and the manual cautions not to run the transmitter without a mic plugged in to avoid excess dissipation in the tube.    And while the original design probably worked OK, whoever owned my radio didn't like the heat built-up inside the compact enclosure and punched a bunch of extra holes along the top.   After 30 minutes of operation outside the cabinet the amount of heat coming off proved this wasn't a bad idea.

All in all there is a lot to like about the CD-144, but a "Gonset Communicator, it ain't".   It's definitely a better radio than the Heathkit Lunchboxes due to it's superhet receiver, but sold for 4 times the price the Lunchboxes would sell for.     Since the Gonset was the only other comparable rig on the market at the time, it's easy to see why the CD-144 fell short, especially for the same almost-$200 price.    It could have been a different ballgame if the price had been around half that, but Deltronic couldn't build it and make money, so that outcome would have been the same.   Deltronic may have been first with a commercial VHF portable but Gonset is the company that did so successfully.

Other than George's and my S/N 0198, the only other owner of a Deltronic CD-144 that has turned up is Ray Grimes N8RG who truly deserves the title of "master restorer" for his work on his radio - see before and after pics to see why.    Given the scarcity of this radio it's great that Ray went to the effort rather than just consigning it to the junk bin.  

George plans to rebuild the power supply of his rig one day, and  his article in #130 is a must-read for anyone interested in the origins of VHF portables, and I'll conclude with the same questions George did:

• Was there any connection between the two companies?
• Did Gonset copy the Deltronic idea and commercialize it?
• Did someone leave Deltronic and go to work for Gonset?

Thanks to George for permitting me to link the copy of his manual here - a copy can be downloaded from the "Attachments" section below.