J-38 Signal corps key's

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The photographs above are of an unknown maker of the J-38 Morse code key. The oval base of the key has a cut-a-way frame unlike found on Lionel keys which have a solid key base. Numerous J-38 keys will be found with square corners as seen above on the black bakelite base.The J-38 key above rests on a 1/2 thick piece of aluminum which was added many years later and is not original. I call this style of J-38 key a "Two tone J-38" due to the two different colors of the hardware. I wish I knew the actual manufacture of the key as that is how I would reference it. Numerous companies produced J-38 keys and did not place any identifying marks on them.

Please also visit my Lionel J-38 page located HERE.

Where does the J-38 name come from?

The short answer is the black base. Remove the straight key from the base and it is no longer a J-38. According toThe Vail Correspondent #10 January 1995 the proper nomenclature for the Signal Corps closed circuit key alone, without a base, is J-30 and is described as being for "general purpose application". Now for the longer answer. The U. S. Signal Corps assigned their telegraph keys with the letter "J" and then a number. This practice started during the WWI era and ended in the 1950's. According to an article by W1IMQ in the The Vail Correspondent #4 July 1993, before 1943 both the Army and Navy had separate nomenclature systems. In 1943 these separate nomenclature systems gave way to the Joint Army Navy nomenclature system(AN System) for all new equipment. Although existing items continued to be made and marked under the old system. The AN nomenclature is known today(1993) as Joint Electronics Type Designation System(JETDS). Under the JETDS nomenclature keys and other keying devices carry the unit indicator KY. Thus the Signal Corps J-45 leg key became known as the KY-116U and KY-562/U. The Vail Correspondent goes on to note that the J-number keys range from 1 to 51. Excluded in that list are the J-8, J-9, J-13, J-39, J-42, J-49, and J-50. According to the book J-Series Telegraph keys of the US Army Signal Corps by Larry Nutting he states that J-49 seems to be an AC motor driven “Automatic Keyer” used with the BC-751. And he notes that J-13 and J-39 appear in a 1946 Signal Corps listing of type-numbered items, but that further information is unavailable.

Unlike the J-37 key which uses a leaf spring, the J-38 employs a coil spring to return the arm after it has been depressed.

The J-38 CW key has a vast and wonderful history behind it. The J-38 key was used by all branches of the U.S. military. The J-38 key was produced by numerous manufacturers in very large numbers during the 1940's and later. Some of these manufacturers(or at least suppliers) were Bunnell, Johnson, Western Electric, Signal Electric Mfg. company, Waters-Conley, and McElroy Electronics Corporation, American Radio Hardware, Manhattan Electrical Supply Company..

Do not be surprised if you have a J-38 key in your collection without a manufacturers name on it. Many of the manufacturers did not place their name on the keys that they produced for whatever reason. Many collectors try to identify the maker of their J-38 key by the physical characteristics of the key. They use such things as the shapes and physical size of the various components along with the types of metals used on these components. But it is a difficult task. There are differences in style between the manufacturers, and slight variations within lots made by each manufacturer. Some manufacturers were based in the same city as other manufacturers so it is possible that they sold parts to each other and used the same suppliers. K6IX has come up with an interesting way to catalog these keys with no maker marks. Visit his excellent J-38 site HERE .

When the J-38 was used for training, each student's key was secured to a table, and was wired into the training system with two wires. One wire was connected to the "LINE" terminals, while the cans(headphones) wire was connected to the "TEL" terminals. With the circuit closer on the key in the closed position, the student could listen to the practice code that was being sent over the line. When the student wanted to practice sending, he would simply open the keys circuit closer and tap away. More information on how this training system was configured can be found in the February 2, 1942 dated United States manual TM 11-432. Of course the J-38 was used for much more then just training, and the history of these telegraph keys and where they were used can be quite fascinating. Although their main use was for training as the J-38 was designed specifically and solely as a code practice key.

The J-38 can sometimes be found in its original training configuration. But when these items were war surplus and selling for .25 cents each many folks removed the back terminals and connecting strip at the end of the key and tossed them. Some would spray paint the frame and base to put it in mufti. Afterwards they turned the key around on the black base which helped secure it so that it would not tip while in use. Today it is becoming increasingly difficult to find one complete.

The picture on the left is of another unknown maker of the J-38 Morse code key. Sadly, one of the terminal screws on the key base is missing. If you know of a source please me.

The picture on the right is of the bottom of the J-38. The red stamp reads as follows "SC7280A". I believe this is an acceptance stamp applied by the U.S. Signal Corps.

The picture on the left is of the rear of the key seen directly above.

Terminal pin replacement:

When J-38’s were war surplus and selling for .25 cents each many folks removed the back terminals and connecting strip at the end of the key and tossed them. Some would spray paint the frame and base to put it in mufti. Afterwards they turned the key around on the black base which helped secure it so that it would not tip while in use. Today it is becoming increasingly difficult to find one complete. Locating missing parts is near impossible.

The terminals on J-38’s have a small pin on the bottom. This pin is used to align the terminals so that the connecting holes are offset at 45 degree angles. The slot for the pin can be seen in the connecting bar directly below the wire cutters. When the J-38 is disassembled the pins are often lost by those not prepared to watch out for them. I have several J-38's that were missing these pins. My solution was to dig through my paperclip collection to find some that were the same diameter as the pins. Afterwards I stuck the paper clip into the pin hole located on the bottom of the terminal. From there I used a wire cutter to snip the paperclip off at the proper length. The red arrow above points to an original pin. The white arrow is pointing to a magnet that is holding a few dozen homemade pins I just made before taking the photograph.

The picture on the left is what some have called an AWM J-38 key. AWM stands for All White Metal. This term was coined after the extreme difficulty in identifying the manufacturer of J-38 keys. Basically it means that we do not know who made the key and since there are no brass parts on it we'll classify it as AWM. Personally though, I find the J-38's which used both brass and "white" metal parts much more appealing. Anyways as can be seen, the J-38 base is missing some parts and has a few extra holes drilled into it.

The picture on the right is a Speed-X key mounted on a J-38 base thus making it a J-38 key. Actually a "real" J-38 never had such a key mounted on the black bakelite base. The bakelite base is missing a few parts but thankfully it has no extra holes drilled into it. The knob on this key is known as a Navy knob. The “Navy type” knob is fitted with a skirt for both comfort and safety. Back in the days when spark gap ruled the airwaves keys were often connected in the transformer’s PRIMARY section. Some keys could handle as much or more current and voltage then used today in modern arc-welders. Stated another way, it could key the arc-welder. The wood base is not original. I have wood floors in my home along with several boxes full of wood flooring. I pulled out a piece of this flooring and cut it down to size then mounted the Speed-X J-38 on it. It actually looks fairly nice so my next step is to pull out the router and put a decorative edge around the wood. To learn more about this Wm M. Nye Co. Inc. Speed-X model 310-003 key please visit HERE.

The photographs above show both the top and bottom of the Japanese JJ-38 code key without its black base. The JJ-38 in these photographs is an imitation J-38 key. The trunion contains 4 ball bearings on each side that the arm rides in. Although according to the Vail Correspondent #10 January 1995, a Japanese collector told the author that these keys had a connection to the "Japanese Self Defense Force". This key is also known as the "Japan ball bearing key" and also as the "AMECO K-4" key. It was made from the early 1950s until 2010. AMECO states that "Due to production problems at the factory in Japan, manufacture of the AMECO K-4 has been discontinued and the keys are no longer available.

While it does not have the quality of the original J-38 keys from the WWII era, the price also reflected that fact and this key would be perfect for a practice set-up for any one interested in sending Morse code.

These next two photographs show both the left and right side of the JJ-38 straight key. In these pictures, the coil spring that was discussed above can be seen. On the underside of this key, the word "JAPAN" has been cast into the metal base.

While this J-38 key sure is a pretty thing, the reader is reminded that it is a imitation. Further more the reader should be aware that there are other "fakes" out there in which the manufacturer made their own black base. I use the word "fake" loosely as I do not think they built these keys to fool anyone. I guess a better word would be "non-authentic". For example the J-38's made by ARTEC have their name cast into the left side of the frame and the circuit closer is attached under the right side key terminal which will cause the terminal to loosen. The legends(wording on the black base) are silk-screened rather than engraved. Plus the nomenclature is "J38" rather than "J-38".

Furthermore:

In November 2020 a someone made a quick post on a CW forum and referred to this key as a Jap J-38 key. The person making the post was probably in a hurry and simply made a quick reply which consisted of just a couple of sentences. Well three American hams became offended because the poster did not spell out the word Japan but instead used the abbreviated word Jap. One of these keyboard warriors even asked for all prior posts using the word Jap to be deleted. Hmm, I wonder if Australians are offended by the term Aussie, Czechoslovakians offended by the term Czech, Americans offended by the term Yank, Britain's offended by the term Britt's, Polish offended by the term Poles, and on and on, or is it just some Americans that are offended?

Whether you are one that is easily offended and have a need to silence others or think this political correctness stuff has gone to far please DO NOT email me. I am simply the messenger and informing you that you will offend some folks if you are in a CW QSO and shorten the word Japanese to Jap or if you call this Japanese made key a “Jap key”. If you call it a Jap key I will not be offended. Call your key what ever you wish.

The comments of those that became offended are as follows:

“Gentlemen, please. It has been several decades since the term "Jap" has been an acceptable way of referring to persons or products of Japanese provenance. You want to know why youth is not attracted to Ham radio, just consider that fact... The next Ham recruit just might be an American of Japanese descent. Common courtesy in 2020 America is to use acceptably polite terminology in public discourse.

Thank you KI5CAW."

"I think this key should be referred to as a Japanese J-38 key if that is what is intended and prior messages on this thread carrying the offensive term be deleted. Thanks for your cooperation.

73 de W2LCQ, Ed Jones"

"I concur. It's time to join the 21st century.

Steve AI9IN'