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AMERICAN MILITARY TELEGRAPH KEYS - - - - - - - - - - - - (8001-9000)

These keys were used by the American Armed Forces in WW-I and WW-II.

(The instruments are in approximate chronological order: Oldest first.)
* = (Items no longer owned.) ** = (Items in other collections.)


Worn Case(15KB) labeled: Signal Corps, U.S.Army. Field Induction Telegraph, Order No. 80191, Date 1918. Mfd. By L.S.Brach Supply Co. Newark, N.J.U.S.A. This set contains a polarized sounder and induction coil and apparently detects the very small voltages induced into the ground by the high voltage transients from the induction coil.

8010b A closer view of the components:(30KB)

8010c A closer view of the telegraph key:(29KB)

8010d A closer view of the schematic diagram:(22KB)

8020 U. S. ARMY WWI FIELD TELEGRAPH SET: (16KB) In well worn brown leather case marked "SERVICE BUZZER, SIGNAL CORPS U. S. ARMY, MODEL 1914. Manufactured by Stromberg Carlson Tel Mfg Co., Rochester, NY IN 1917. A tiny Telegraph key is integrated into the unit and can be pressed with the cover closed in mud and rain through a thin leather area on the cover. Includes the original headphones and hard-to-find adjusting tools.


8021, a, b, * Same as above but mfg in 1918:(35KB) Less headphones & adjusting tools.

8040 * WWI FIELD TELEGRAPH/TELEPHONE SET: (18KB) Enclosed in a nicely finished wooden box, this set contains the same style of key that is found in the WWI 1914 service buzzer set. The handset hangs on a hook which folds out of the case and there is a ringing magneto with folding crank handle and battery compartment for "D" cells. Manufactured by KELLOGG SWITCHBOARD SUPPLY CO., Chicago, U.S.A.

8040a A view with the cover open: (13KB)

8040b A closer view of the telegraph key: (17KB)

8040c A view of the schematic wiring diagram: (22KB)

8040d A close view of the label: (17KB)
8042 * Same as above.

8090 * LEAD MINIATURE NAVAL TELEGRAPH SIGNALERS:(16KB)This set of miniature sailors holding telegraph semaphore signal flags was probably used for training purposes.

8090a A closeer view of a miniature sailor:(13KB)

8120 U.S. ARMY WWII TG5A FIELD TELEGRAPH SET:(16KB) J41A Olive drab metal box with electronic components, swing-down front with special J-41 key which is similar to a J-37 but with extra contacts.

8120a J-41 KEY:(17KB)This key is identical to a J-37 but it has an extra set of normally-closed contacts at the far end for use in the TG5A field sets.

8121 * U.S. ARMY WWII TG5A FIELD TELEGRAPH SET:(12KB) Similar to 8120.

8130 * SCR-578 'GIBSON GIRL' EMERGENCY TRANSMITTER / SOS KEYER:(20KB)This is the standard emergency transmitter used throughout WW-2 for sending out distress signals from lifeboats. It consists of a hand cranked transmitter which sends out automatic SOS signals or hand-sent code messages with a built-in key. The transmitter is a nearly exact copy of the earlier German NG-2 NOTSENDER. It is shaped to fit between the operator's legs and to be strapped in that position as the operator turns the crank. The box is shaped somewhat like the female figure and this is apparently where it got its name.

These devices were supplied with a long-wire antenna on a built-in reel:(20KB)

The Front Panel contains a very simple push-button telegraph key for manual signaling:(20KB)

There are detailed Instructions on the operation of the unit:(20KB) printed on the top.

The hand crank is stored in a recess on the rear of the unit:(20KB)

When I was a young ham radio operator, these radio sets could be bought for $ 5.00 on Radio Row in downtown New York. They came with a wonderful kite as well as a number of large balloons and hydrogen generators for filling the balloons which were used to raise the long wire antenna several hundred feet into the aid. We used to fill the balloons with hydrogen by immersing the generators in water. We would then send the balloons up with a postcard asking the finder to mail the card and tell us where the balloon came to rest. We sent up a total of 8 balloons but no postcards were ever returned... This was a big disappointment for a young boy...

8140 * RT-6 SPY TRANSMITTER WITH TINY BUILT-IN SWING OUT KEY.Tiny transmitter part of a complete clandestine radio set. 2E26 pwr amp & VY tiny telegraph key which folds out from case.Traded to Joel Kosoff, W3ZT

8150 * RS-3 SPY TRANSMITTER WITH TINY BUILT-IN TELEGRAPH KEY:(35KB) This transmitter is part of a complete clandestine radio set and the tiny telegraph key is so nicely designed that it is sometimes removed from the transmitter and mounted on a base of its own.

8150a * Close-up view of the tiny Spy key:(20KB)

8160 VERY UNUSUAL AIRCRAFT KEY:(9KB) Tiny key on 2-1/8 x 1-3/16" parallelogram base Pivoted knob. Removed from WWII bomber. Extremely unusual. Unknown function. Looking for more information.

8180 THE MOST UNUSUAL MILITARY KEY I HAVE EVER SEEN!!:(13KB) This is an exceptionally unusual key with what would have been the back portion of the frame mounted above the front portion of the frame. I suspect that this was done to allow the key to be mounted against a vertical panel such as you would find on a radio set. The fact that the key has no shorting switch is further evidence that it is a radio key and not a land-line key. I am looking for more information on this weird key.

8200 VERY EARLY EXPLOSION-PROOF KEY: (19KB) This very unusual all plated key integrated onto a wooden base has its contacts sealed by a rubber diaphram in a 1-1/2 inch diameter metal cylinder to prevent sparking in explosive atmospheres. It was typically mounted on the front of the BC-9 Transmitter.

8201 * EARLY EXPLOSION-PROOF KEY FROM BC-9:(16KB) This example of the key shows the mounting hinges for the BC-9 panel.->W2PM

8211 ** J-2 WORLD WAR I MILITARY KEY: This WW-I Spark key has the familiar oval nickel plated frame with coil spring running into hole in frame near the HEAVY DUTY 1/4" unscrewable contacts. No Shorting lever. Key mounted on a 1/2" thick 5-1/2 X 3-1/4" bakelite base with all wires totally sealed in base. Marked: "SIGNAL CORPS, US ARMY Order No. 40416, Type No. J-2" on top of bakelite base and stamped SC105A in red ink on side of base. It was made by MESCO (Manhattan Electric Supply Co.) as indicated by the stamped 'MESCO' on the oval frame. Photos courtesy of Collector K8OMO.

8211a ** A closer view of the lettering on top of the base:

8211b ** A closer view of the MESCO label on top of the oval frame:

8211c ** The bottom of the base of the J-2 Key:

8210.gif Another J-2 World War I Military Key:(15KB)

8212 * J-2 MILITARY KEY:(12KB) Similar to 8210 but made by Signal Electric Company with company name stamped into base.

8220 J-6 L.S.BRACH MILITARY KEY: (25KB) Incorrectly advertised and sold widely as a J-3, this key has a straight, heavy 1/2 X 3/8 X 5-1/4" brass lever with typically- British design pull-down spring at far end of pivot. The base is 1/2" thick, 4" long, and 1-3/4" wide and tapers down to 5/8" wide from pivot toward knob.

The lever is stamped(20KB): L.S.BRACH SUPPLY CO. Newark, N.J. U.S.A. The Bottom of the base has a 1 X 1" painted square with A-12 and an upward-pinting arrow inside. The wires are sealed inside the base.

8230 * J-3 WORLD WAR I MILITARY FOLDING KEYS:(42KB) These keys are often found with either Fahnstock clips or screw-in terminals. They have a lever that swings to the side. The keys were used inside a field set that I am still trying to locate and identify.

8235 ** J-4 SILENCED INSTRUMENT KEY / SET:(9KB) This unusual key is silenced by placing rubber bunpers on its contacts and adjusting screws. It was probably used as a practice key and the clicks were eliminated to avoid bothering nearby students in a large classroom. An alternative explanation comes to mind since this one is mounted on a board with a light. It may have been used to train operators to copy light signals and the silenced contacts prevented them from copying the sounds, forcing them to concentrate entirely on the light signals. (This key is in the Pete Malvasi - W2PM collection.)

8240 FLAME PROOF KEY AND WINKER: (34KB) Type C.Q.1140 Serial No. (blank) mfg by INTERNATIONAL RADIO TELEGRAPH COMPANY. This set consists of a flameproof key similar to the J-5-A mounted on a black bakelite base along with a metal- enclosed light socket. I have been told that this set was used in aircraft to give the radio operator visual feedback when he pressed the key to overcome the high noise levels in early aircraft. Socket missing.

8244 FLAME PROOF KEY AND WINKER: As above with J-5 key Manufacturedd by General Radio. 8248 FLAME PROOF KEY AND WINKER: Slightly smaller version of #8240.

8250 AIRPLANE FLAME PROOF RADIO KEY:(14KB) Similar to J5A below but all brass with cover labeled: Airplane Flame Proof Radio Key Type CAG 1169. Made for Navy Department BU of SE. General Radio Co. Cambridge Mass.

8250a A closer view of the nameplate/cover:(31KB)

8260 FLAMEPROOF KEY J-5-A:(17KB) Round cylindrical sealed key with large doorknob style knob. Cover marked: SIGNAL CORPS. U. S. ARMY. FLAME PROOF KEY J-5-A. Order No. 583-Phila-42. Made by L. S. Branch Mfg. Co. Newark, N.J.
8262, 8264 * Same as above. Order Number 2670 NY 41.

8266 * FLAMEPROOF KEY J-5-A:(20KB Same as 8262 above IN ORIGINAL BOX.

8270 U.S. ARMY J-12 KEY:(18KB) This brass key is riveted to a rectangular metal base and stamped J-12.

8272 * U.S. ARMY J-12 KEY ON ROUND BASE: This brass key is mounted on a round metal base that allows it to rotate. The key is stamped "TELEGRAPH KEY J-12". These photographs were sent to me by another collector.

8272a * Another view of the round-based J-12 key

8272b * A close view of the stamped lettering on the round-based J-12 key

8272c * A view of the bottom of the base of the round-based J-12 key

8280 U.S. NAVY FLAMEPROOF GENERAL PURPOSE KEY XXX-26003A:(38KB) This is the widely used navy key with the "Navy Knob", a doorknob style knob with flat base under it. Made for the navy by several manufacturers whose code letters precede the model number. For instance, CJB-26003A was made by J. H. Bunnell. CTE-26003A was made by Telephonics. CMK-26003A was amde by McElroy, etc. It was apparently copied from the German Luftwaffe Key of very similar design (See German Keys.).

8280 Another view of a CMI-26003A Navy key:(16KB) The CMI indicates that it was made by the Moulded Insulator Co.
8282,8284 * Same as above CTE-26003A.
8286, 8288 * As above - not labeled.

8290 * SWITCHBOX MOUNTED NAVY FLAMEPROOF KEY:(16KB) Same as 8280 above but mounted on large shipboard style grey box with label: GENERAL ELECTRIC SIGNAL KEY Cat 8259229G2 Type CMI-26003A with capacitor.

8295 UNUSUAL VARIANT OF THE NAVY FLAMEPROOF GENERAL PURPOSE KEY:(15KB)This key carries no identifying marks of any kind. It is very similar to the American and German keys of similar design but the rounded protrusions on either side are different.

8298 NAVY CLT-26001B GENERAL PURPOSE KEY:(23KB) This key was made by the Lundquist Tool and Manufacturing Co. of Worcester, Mass in 1942 as shown by:

The Label on the original box:(8KB)

8310 "LIONEL" MILITARY BUG (Semi-automatic key) J-36. (See # 7920)

8315 RARE McELROY MILITARY J-38 STRAIGHT KEY:(16KB) This is the key that McElroy Electronics Co. built for the U.S. Military. The only known example was in the McElroy collection until a small number of them showed up at the 1999 Dayton hamfest.

This is another view of the key:(16KB)

This is a close-up view of the M in the work McElroy as it appears under the hot contact strip:(23KB)

This is a close-up view of the narrow clearance between the shorting lever screw and the gap adjusting screw:(35KB)

8320 "LIONEL" MILITARY GENERAL PURPOSE KEY J-38:(12KB) This is the straight key which was manufactured for the military by the Lionel Toy Company during WWII. It has a solid black cast metal base which carries the (L) symbol and is marked "The Lionel Corporation, New York, N.Y. in the center of the top. Most examples have brass hardware and shorting levers and a steel lever and are mounted on a black bakelite base which is inscribed J-38 and includes "Line" and "Tel" terminals. The bottom of the base usually has

a large letter "L" cast into it.(13KB)

This is the label on the end of the Lionel J-38 box:(42KB)

This is the logo on top of the Lionel J-38 box:(30KB)
8322, 8324, 8326. * Same as above in varying conditions. 1 with base missing.

8340 MILITARY GENERAL PURPOSE KEY J-38:(23KB) This is a widely used WWII military key. Nickel plated key with shorting lever mounted on a black bakelite base with squared corners inscribed J-38, & with "Line" and "Tel" terminals.
8342, 8344, * As above with brass shorting lever & screws. Some w/o base.

8350 UNUSUAL VERSION OF THE MILITARY GENERAL PURPOSE KEY J-38:(23KB) This key appears to be made of Stainless Steel. Unfortunately, it is not possible to identify who made it or why they used a hollow base and stainless steel.

8360 MILITARY GENERAL PURPOSE KEY J-37:(16KB) This is probably the most widely used of the WWII military keys. The key has a black ovoid plastic base inscribed J-37 & either brass or plated screws. The levers are plain laquered, nickel plated or black anodized steel & the keys are either unmounted or mounted on black bakelite bases.
8362, 8364, 8366. * Same as above with no base plate.

8368 J-37 KEY ON CODE PRACTICE SET BASE:(18KB) This key was used with a military code practice set and its base allowed the wire to be wrapped around the center of the base for storage.

8370 J-44 KEY SET:(16KB) This set consists of a J-37 key mounted on a J-44 base with a switch for "voice" or "telegraph" modes.

8380 MILITARY LIGHT SIGNALLING KEY J-46: (14KB) Very unusual small rectangular based strap type key in original 1942 box. Used for light signalling. Mfg by Winslow.
NOTE: The Navy Code designation for the Winslow Company is CAKU.

8390 MILITARY GENERAL PURPOSE KEY J-47:(33KB) This is a J-37 on a black base marked J-47.
8392, 8394. * Same as above.

8420 J-48 SIGNAL CORPS FIELD RADIO KEY: (24KB) This is an oval-based metal key mounted on an olive drab wrinkle finished base w/matching cover.The cover has a clip for the PL-55 1/4 inch phone plug. This key was used with many of the field sets such as BC-654.

8420a A view of the J-48 key with cover removed:(21KB)

8460 WW-2 MILITARY STRAP-ON-THE-LEG KEY: This is a special J-37 key with profile narrowed by placing pivot adjustment screws locking collars on the inside of the support posts. The key is enclosed in a steel box with galvanized base and black painted cover. Two leg straps are attached to the bottom of the box and used to attach the key to the leg of the aircraft or tank radio operator. Cotton covered electrical cable with PL55 at the end.
8462 * Same as above.
8464 * Same as above with leg straps and wire missing.

8470 BUNNELL WW-2 MILITARY STRAP-ON-THE-LEG KEY:(25KB) This is an unusual variation of the above key. The metal box is somewhat larger but the key is entirely different. It has a doorknob style knob and looks like a very large version of the British 8 Amp key. It is all brass integrated onto the black plastic base which is marked "J.H.Bunnell & Co. New York, USA". The knob is marked: KEY AND PLUG ASSEMBLY NO. 9.

8470a View of the key with the cover removed:(23KB)

8470b Close-up view of the Bunnell Label:(14KB)

8470c Close-up view of the knob showing the ID marking:(14KB)

8520.gif MILITARY CLIP-ON-THE-LEG KEY TYPE J-45:(40KB) This is a standard J-37 key screwed to a black painted steel plate which is hinged to a large clip which is clipped to the leg of the WWII aircraft/tank radio operator.

8520a MILITARY CLIP-ON-THE-LEG KEY TYPE J-45 IN ORIGINAL BOX:(28KB) This is a standard J-37 key screwed to a black painted steel plate which is hinged to a large clip which is clipped to the leg of the WWII aircraft/tank radio operator. As you can see, the box label indicates that it was made by General Electric in Schenectady, NY.

8520b Closeup of Label on Box for J-45 KEY:(32KB)
8522, 8524, 8526. * Same as above.

8540 MILITARY SIGNAL LIGHT KEY J-51:(34KB) This is a hard-to-find key which consists of two strips of metal which are held in the hand like a gun or scissors, and brought together to make contact and send a light signal with an external light gun. The key and light gun and tripod and other accessories and carrying cases constitute the SE-11 Signalling set. The key is supplied with a long wire cord so that the operator can stand FAR away from the light gun while sending signals. The light gun is obviously a tempting target for any enemy and therefore the long cord was literally a life-saver. Most of these keys are painted olive drab and engraved J-51. Other models are painted black.

8540a The J-51 Key with Original Packing and long cord and pictures of complete SE-11 setup:(30KB)

8540b The technical manual illustrations of the complete SE-11 set:(38KB)

8540c All of the individual parts of the SE-11 Light Signalling kit laid out on a table:(31KB)

8540d Two of the carrying bags for SE-11 Light Signalling kits laid out on a table:(27KB)
8542, 8544, 8546. * Same as above.
8550, 8552. * Same as above but black.

8620 TINY WEATHERPROOFED MILITARY FIELD KEY:(19KB) 1-1/2 inch cube with key and send receive toggle switch enclosed in a slightly disintegrating rubber cover. Olive-drab wrinkle finish. Bottom of cube stamped CAY-26013.

8630 * TINY UNUSUAL TELEGRAPH KEY IN BOX FOR WW-II BC-451 RADIO SET:(39KB) This tiny key is constructed in a very unusual way. Its knob is at one end of its lever which is totally enclosed inside a spring. The other end of the lever has the electrical contacts. The key is integrated into the control box for the BC-451A radio set. It is in a parallel circuit with the external key jack so either an external key or this internal key may be used. The label indicates that it was made by Western Electric in New York and it carries serial number 1821.

8630a * A view of the back of the box showing the key mechanism:(40KB)

8630b * A closer view of the unique mechanism of the tiny telegraph key:(35KB)

8640 LIGHT SIGNALLING KEY IN CAST ALUMINUM BOX:(17KB) This key was used for blinking the ship's lights from the bridge. It has a round lever sticking out of a cast aluminum case which is painted grey. Two metal knurled adjusting knobs on top of the case are labeled "GAP" and "TENSION". The key was used on the SB-315 B/U Control Panel in Essex Class Carriers. They were made for the Navy Department by Dittmore - Freimuth Corp in Milwaukee, Wisconsin under contract number N126-03948A. A later model was made for use on the Triton Atomic Submarines. Its Federal Stock Number is FSN 5805 608 0129.

8680 MILITARY KEY:(14KB) This key is mounted on a bakelite base that carries the number D165581 on the bottom. Often mistaken for a Navy key, the key was mounted and used on a large and heavy Telegraph/Teletype terminal set. Since most keys were removed from the rather useless sets, it was only recently that I was able to purchase a complete set. (See 8680a).

8680a MILITARY TELEGRAPH/TELETYPE SET:(43KB) Contains key number 8680 above.

8700 XXX-26012A MILITARY KEY:(15KB) This key is mounted on an oval bakelite base with a slot in the left side for the insertion of a wedge connector for a bug. Its left trunnion support is labeled "GND".

8705 * McELROY CAPH 26012B MILITARY KEY:(10KB) This must have been one of the very few model CAPH 26012B keys which were made by Ted McElroy's company: TELEGRAPH APPARATUS CORP in Chicago. McElroy CAPH 26012B keys are VERY hard to find. The code CAPH is the Navy code for keys manufactured by McElroy: The key is in new condition and is complete with it's original box which shows the manufacture date of 1944. The all brass key is mounted on an oval bakelite base with a slot in the left side for the insertion of a wedge connector for a bug. Its left trunnion support is labeled "GND" in very light stamping.(Traded to: Tom French W1IMQ ''The McElroy Collector''.)

8705a The label on the original CAPH 26012B box:(21KB)

8705b The CAPH label on the base of the key:(12KB)

8705c A Left side view of the CAPH 26012B key:(11KB)

8705d A Right side view of the CAPH 26012B key:(11KB)

8810 * LARGE NAVY FLAMEPROOF LIGHT SIGNALING KEY:(10KB) This huge key was used for keying the external lights on a Navy ship. Its contacts are enclosed in a large metal drum both to protect them from salt water and to ensure that any sparks made by the contacts will not cause an explosion. The label reads: MIL-C-24174/3-001 SIB. Date of Manufacture, 1977. Further down the line, there was typically another switch that prevented accidental 'showing of a light' during night operations.

8810a Another view of the flameproof key:(11KB)

8810b A close view of the telegraph key lever:(15KB)

8810c A view of the spark suppressing network inside the key:(21KB)

8810d Another view inside the key showing the contacts:(17KB)

8840, 8842 MILITARY CLIP-ON-THE-LEG KEY TYPE KY-116/U: This is a much more recent version of the J-45 set with a modern J-37 key.

8860 RECENT MILITARY GENERAL PURPOSE KEY: An all nickel plated key patterned after the Bunnell "Triumph" design. Lever is inscribed WINSLOW TELE-TRONICS INC. 66150. The Plated cast base is inscribed 26001-C and 66150.
NOTE: The Navy Code designation for the Winslow Company is CAKU.

8870 MILITARY "BRELCO" KEY:(14KB) This recent key was mounted on a leg clamp or directly on a transceiver. It carries a label which reads: CAQZ-26026. Nxsr-60008. 9471.

8875 RUBBER ENCLOSED AND SEALED MILITARY KEY:(23KB) This recent key was mounted on a leg clamp or directly on a transceiver using exactly the same base as number 8870. The entire key is enclosed in a soft rubber boot.

8875a Disassembling the key:(56KB) reveals a classic bunnell-style triumph design key complete with contact strip for wedge connector to a bug. Since the key is entirely sealed, this connection could not have been used.

8880 VERY LIGHT STRAP-ON-THE-LEG KEY:(34KB) This all Nylon? key is very light and has two velcro straps to hold it to operator's leg. 5 pin plug on coil-cord. Base marked KEY KY-605U, ELECTRO VOICE, INC CONTR DAAB07-76-C- 0363. As contract number shows, it was manufactured in 1976. Very unusual.

8900 ** AN / GSC-T1 CODE TRAINING SET:(19KB) This set was designed to provide audio code practice tones sent by an instructor and to allow up to 10 students to send code. It consists of a tube-type audio oscillator and amplifier contained in a heavy metal and wood case. The cover swings upward and stores a total of 10 J-37 telegraph keys mounted on special plastic bases which are notched to allow the connecting wire to be wrapped around the key and base for storage (See
Key number 8368.) (Pictures are from the Derek Cohn - WB0TUA Collection.)

8900a Close-up view of cover showing keys:(21KB)

8900b Close-up view of oscillator/amplifier:(18KB)

8905 SPECIAL J-37 KEY ON PLASTIC WIREHOLDER BASE:(19KB) These keys were mounted on these special bases to allow the wires to be wrapped around the key and base for storage inside the cover of the (number 8900) GSC-T1 code practice set above.

8920 ** TG-34A TELEGRAPH TRAINING MACHINE:(16KB) This set was designed to automatically send audio tone dot and dash signals at varying speeds for students to practice copying by hand or on a typewriter. A variable speed motor pulled a paper tape past a photoelectric tube. A light on one side of the tape shined through the tape unless it was blocked by black ink marks on the tape. The ink marks determined when the oscillator would be keyed to make the tones. (These pictures are from the Derek Cohn - WB0TUA Collection.)

8920a Close-up view of the motor and audio panel:(23KB)

8980 U.S.ARMY M-108 POCKET-SIZED BURST CODE KEYER:(25KB) This is a very small telegraph burst encoder set which can easily be concealed in a pocket. It is used to send extremely high speed bursts of ciphertext messages in the international Morse Code. These extremely short and fast messages are difficult for an enemy to receive since they are only on the air for a very short time. The short duration of the message burst also makes it difficult for the enemy to use direction finding radios to pinpoint the location of the transmitter. The coding unit (on the right) punches morse coded holes in a tape which is then sent in a short, high speed burst, by the spring driven sending unit (on the left).

8980a A view of the other side of the coding unit:(17KB)

8980b A view of the Alpha code wheel:(46KB)

8980c A view of the Morse code wheel:(45KB)

8980d A view of both units with covers open:(38KB)

8980e A closer view of the spring wound burst sending unit:(36KB)

8980f A closer view of the Morse coding unit with cover open:(45KB)

8980g A closer view of the Morse coding unit with cover open and sub-cover removed:(51KB)

8980h A different perspective view of the Morse coding unit:(48KB)

8980i Another different perspective view of the Morse coding unit showing both coding wheels:(38KB)


Professor Tom Perera
Montclair State University

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