For information on McElroy models, serial numbers, etc, see this page.
All items are subject to prior sale, so e-mail me before paying to check that what you are interested in is still available, to confirm shipping cost, or to ask questions. In the winter we may be out west in our trailer and might not have your item with us (although we can place a hold on an item to reserve it for you). Our email address is
We accept US payment by paypal.com (made to any of our email addresses), by money order, or by personal check with your shipping address imprinted on it. Foreign payment may be made by paypal or by international postal money order. If you pay by mail, let me know and I will hold your item for you.
Shipping costs are not cumulative. If you are interested in different items, I will provide shipping cost. Some small items will ship with a bug at no added cost. But others may be best shipped separately; for example, it is cheaper to ship a few knobs (first class mail) separate from a book (media mail) since knobs cannot be included with media mail.
Shipping in the USA of any BUG KEY on this page is $13.00 and of any HAND KEY is $7.00 (unless otherwise stated). Elsewhere, inquire.
Telegraph Apparatus Company (TAC) is included on this page. TAC is commonly said to have been "one of Ted McElroy's companies." More precisely, it was a partnership ("not inc." as the nameplates read) set up in Chicago by Ted McElroy and his friends and business associates Joe Goode and Frank Bascomb. It produced civilian keys and code instruments during WWII, while McElroy's Massachusetts operation was busy making equipment for the Signal Corps.
Please note: Keys are generally original, complete and operable except as noted, and may need cleaning (usually, simply washing to remove dust). Other electrical and electronic items have not been used or tested, and are sold as found, unless otherwise noted.
For general information on all of the McElroy bugs, click here.
For recent additions to this page, you can click on the small photo for a larger photo.
Equipment is listed below in this order:
McElroy Signal Corps J-38 keys (if we have any) will be on the J-38 keys page.
#912EOY John McElroy key
In the 1960s, John McElroy, Ted's son, decided to offer the professional quality telegraph keys that his father sold in the 1930s. He started to advertise the "professional model key" with flyers in 1965. Three years later, an ad appeared in QST (November 1968). He received a feworders, and finally started shipping them in early 1969.
The main lever is stamped with McElroy Electronics Corp. The key came in a plastic case, accompanied by a plastic McElroy clutch-back key pin. A metal plate on the box lid would be stamped with your name or call. In the early 1990s John told me he was disappointed with the sales, and guessed that he sold maybe 100 of them.
For some reason I cannot close the case lid, the key parts are too high ... same story with the one in my own collection (the only two complete sets I have found in twenty years). I must be doing something wrong. Displayed, of course, the lid would be open anyway.
I polished the main lever of the key a bit (using nevr-dull magic wadding) but the key does need cleaning. The case has a small chip in the back.
All the items.
Close-up of key.
Another view of the key.
$395.00 (S&H = $10.00)
The "Mac straight key" was McElroy's first hand key, appearing in 1937. It is an open circuit key with a cast iron base measuring 2-5/8 x 5-1/8 inches. It has two small holes at the back where an optional "hummer" (3-volt mechanical oscillator) could be mounted; a larger hole at the back was for the hummer wires. The two holes at the front are for additional wire terminals (perhaps used to select hummer or regular key operation, or for headphones, which McElroy said could be used for practice).
Since the key has no identification on it, it is often bypassed as nothing special - but it is a scarce McElroy key. It also makes an interesting and unusual hand key for an amateur radio operating desk. Our Mac straight keys are shown below.
#M607CGR Mac straight key.
This Mac straight key once had a hummer on the base. The lever plating on this key is pitted and has surface rust; the finish shows its age (this is one key where the base would benefit from a good scrubbing and oiling).
$65.00 (S&H = $8.00)
#413BTH Straight key
A very unusual McElroy first hand key -- copper stripes show through the base finish, as though Mac was trying out a tiger-stripe finish (found on many Bunnell Barclay relays).
$69.00 (S&H = $8.00)
#912COR Straight key
This one had a hummer on it, and it still has the extra terminals near the front contacts. It is in excellent as-found condition.
$89.00 (S&H = $8.00)
#912COR Straight key
This one appears to have been originally purchased simply as the key (without hummer). It is in excellent as-found condition.
$85.00 (S&H = $8.00)
#810TTP Straight key with hummer
The McElroy straight key is scarce; to find one with the hummer is rare. McElroy described the hummer as a 1000 cycle mechanical oscillator for operation on 3 to 4.5 volts DC; one flyer states that it can be used with headphones (perhaps the reason for the added terminals on the key).
The two black hummer wires show continuity; I have not tested it further. The finish on the key is in unusually good condition; the hummer shows some wear. This is a great addition to a McELroy collection.
$295.00 (S&H = $12.00)
#205BER black early Streamkey
This is the first style Streamkey, but with a black wrinkle base and without the triangular nameplate. It was never advertised. Based on the pivot hardware (similar to that on McElroy's 1937 "hand key") this may be his first cut of the Streamkey. Another possibility is that it is the last of the first model, sold when he ran out of nameplates and then made a "standard" version. In any case, this is complete, original, and rare.
$175.00 (S&H = $8.00)
#404BSX McElroy first Streamkey.
This is the first model "streamkey" offered in ads by Ted McElroy, dating from 1938. Unlike later teardrop hand keys which have a bulbous pear shape, this scarce early model has a relatively flat base, and a triangular metal nameplate (the only Mac hand key with a metal nameplate).
One of the nicest I have seen: Excellent condition, slight wear on the top of the knob, the screw holding the circuit closer lever has light patina, but there is no wear at all on the CC lever.
$345.00 (S&H = $8.00)
#1112CAY model BB-300 Stream key
Some collectors consider the second type deluxe Streamkey (the chrome plated model 300) to be the most beautiful of McElroy's hand keys. And this one is the scarcest of the model 300s: the BB-300 with ball bearing pivots. Note the ground pigtail from the lever to the wire terminal.
The spring appears to be a replacement; the lever seems to be bent down toward the knob (see photo). The chrome is in excellent condition and the circuit closer has no marks (appears never to have been used). If you want just one late model Streamkey, this may be it.
With the ball bearing streamkeys, be forewarned: if you disassemble it. do so over a container (those bearings will roll away), and you will need three hands to reassemble it!
Photo of bearing.
Side view for lever.
Photo of ground pigtail.
#310BGE model BB-200 Stream key
A BB-200, indicating it is the second style Streamkey with a black wrinkle base and ball bearing pivots. It includes a circuit closer and a ground pigtail on the lever, but has the simpler type terminals. A nice heavy key that stays where you put it (although it does have screw holes available in the base).
The spring is not the usual thin conical shape but I believe it is original to the key. This scarce model is in very good condition and appears to have had little use.
Photo of bearing.
$145.00 (S&H = $8.00)
#M606CBD TAC zinc Streamkey copy.
Here's my opinion on what some have called a "fake McElroy" key: I believe it was a hurry-up job for the Signal Corps during WWII by Telegraph Apparatus Company (a McElroy partnership located in Chicago). The base is cast zinc, which tended to warp when cooled, and to lose the painted finish. The base on this wobbles slightly (can be smoothed or screwed down), otherwise it operates well. This key is original and complete and (apart from the warp) in very good condition. An interesting collectible.
$49.00 (S&H = $7.00)
#M491CEG TAC cut-off key
Telegraph Apparatus Company (TAC, a McElroy partnership in Chicago) "cut-off" key. This key was used in the 1940s inside the TAC code practice oscillators; the cast iron base was shortened so that the lever could protrude from the front of the panel. These models are scarce to find either in or out of an oscillator.
From the solder on the terminal lugs, this was probably removed from an oscillator. The chrome lever is freckled, and the screws have surface rust. Larger photo.
#MAC-S100A plastic hand key
This is the scarce black plastic model S-100 or "Professional" Stream Key. This has the chromed parts and circuit closer. Cast into the base at the back is "radio telegraph transmitting key," and at t he front is "Stream Key, manufactured by T.R. McElroy, Boston Mass. USA." The key offered here has all knurled hardware but for the terminal nuts. It has a burnish in the plastic and a small crack at the back (beyond the gap adjust screw), and a smaller burnish in the plastic at the front - see the photos.
So, where are the wire connector terminals on the early Mac-Keys? Not until the model 1936B (type 2 lever: flat levers with separate pivots) did McElroy deign to accomodate amateurs and put terminals out in the open on the base. Prior to that, the terminals were simply a part of the hardware used to mount various pieces of the key. In this photo Jim, W0EB, shows us where they are on an early 1936A bug.
#414TTO 1936A Mac Key.
If one of the many models and variations could be considered the "typical" Mac-Key, this might be it: The 1936A with cast pivot assembly and small aluminum nameplate. This one is serial number 8215. All of the upper parts, brass and steel, are cad plated. It has both of its original large weights, and unlike many bugs this one will operate at a low (18 - 20 WPM) speed.
This Mac-Key is in excellent condition; the base finish is one of the best I've seen. If I had to find a flaw, I would say the knob may be an old replacement. All of the other parts are original, right down to the pendulum clip (so this bug can be tipped on its left side and operated as a straight key).
This would be a fine addition to any key collection, or for your operating desk.
Left side view.
Right side view.
#893TGY 1936A Mac Key with pendulum extension.
The most common way to slow down a bug is to add more weight, but the best way is to place the weight further out on the pendulum. Pendulum extensions have been around for a century or more, but most were aftermarket devices. Ted McElroy seemed to consider this solution for his 1936 bug, but I know of only two Mac Keys that incorporated it. This is one of them.
This rare 1936A (serial number 7305 on an aluminum plate) has a threaded insert at the end of the pendulum. The 1-1/4" extension has a tapped hole, and screws onto the pendulum. (When I obtained this bug it was missing the extension, so I had one made to match the other known extension.) With the single weight, it slows down nicely and generates beautiful Morse. This key also has the original pendulum clip, so that you can lock the pendulum, turn the key on its side, and use it as a straight key.
I have had this key in my personal collection for oever 20 years. It is in excellent condition. The brass upper parts are cad plated; the base has no chips or flaws.
The threaded pendulum insert.
The extension again.
Bottom cast legend.
#499MI ... 1938A Deluxe Mac Key.
The rare first Marbleite finished Mac-Key, and the last Mac to have the separate pivots for the dot and dash levers. Less than a dozen 1938A models are known; all are Deluxe. Only two have a four-digit serial number; this one is 1730.
I obtained this as shown: There is a plastic ring on the damper wheel, perhaps placed there by a previous owner to quiet the bug. The U-bar holding the fixed contacts has been cut, and re-connected with a wire; this may have been a "factory fix" -- perhaps the slot in the bar was too short, or the assembler couldn't get it to line up in the cast supports. McElroy was known to resort to such "gimmicks" on his keys.
The key looks like it should work, but there is a short somewhere -- maybe in that U-bar fix! I leave the repair to the buyer. The Marbleite base finish is very good (most early Marbleite was poorly applied, perhaps a learning process) and there are no chips. The nameplate does, however, have some paint loss (see photo).
The separate lever pivots.
The cut U-bar.
$245.00 (S&H = $12.00)
#MAC325 1938B Mac Key
This is a model 1938B Standard bug. The large nameplate seen here was first used on the 1938 models, and the 1938B is the first use of the common-pivot levers (compare the 1938A above). It is complete, original, and in excellent condition. There are a couple of small chips in the black wrinkle finish on the left side, and barely noticable ones at the ends of the T-bar. Otherwise it is one of the finest of this model you will come across.
#MAC301 1939 Deluxe Mac Key.
The most beautiful bug ever made ... the 1939 McElroy Deluxe, with its improved T-bar, Marbleite base and chromed parts. The unique finish on this key was first used on the 1938 Deluxe model; by 1939 McElroy got it right.
This bug has two large weights with the knurled screws (fillister head screws were also used in 1938 - 39), and ground pigtails on both the dash and main levers.
Condition: Other than a small chip at the back right corner, the finish is flawless (see photo below; I actually did not notice this little defect on the key until I examined the photo); the nameplate is perfect; the paddle is not original. I doubt you will ever find a prettier bug for your operating desk.
Another view. Nameplate and back corner view. Front view.
#493ABX ... 1939 Standard Mac Key.
While the Deluxe 1939 had a circuit closer (and the beautiful Marbleite finish), the Standard did not. The 1939 Mac Keys were that last to carry a serialized nameplate; this one is 6775 (the 5 appears to have been stamped over a 4). It has one original weight, and non-original paddles. The black base finish is excellent; an application of gun oil would really make it stand out. The nameplate has no paint loss; it may clean up very well.
Yet another view.
$245.00 (S&H = $12.00)
#0407CHY McElroy No. 500.
This is the No. 500, the last of the large T-bar bugs, with the standard black wrinkle finish and no circuit closer (although they had the screw-hole for the lever). This one does not have the decals - they were either not applied (perhaps an end-of-the-line bug) or an early owner washed the key, destroying the decals. One of the paddle screws is incorrect, the knob is a replacement, and it has but one weight. Thus a low price for this impressive Mac Key. (Click on the photo for a larger view.) Another view.
$175.00 (S&H = $12.00)
#137 McElroy S-600 Streamspeed.
T.R. McElroy's famed "teardrop" bug, one of the last made by McElroy (1941). This variation is the one with three mounting holes in the base. This one is complete and original, it has both weights, and an excellent nameplate. There are two small freckles in the chrome (see second photo, they are on the base next to the reflection of the weights); the rest of the chrome will polish up nicely. Overall a scarce and beautiful model in unusually good condition.
#MAC465A model P-500 Mac Key
This is a model P-500 from 1941. It is the first Mac Key to use the small, no-number nameplate (the photo is of this plate). It is complete, original, and is in excellent condition -- so good it may in fact be unused. The circuit closing lever looks like it has never been closed! You will not find a better P-500. A bit dusty, needs cleaning. Second photo
#161 McElroy model A-400.
This bug is the "missing link" between the T-bar frame bugs and the P-500 model. Note the lack of protruding T-bar tabs on the frame, and the fixed contact posts. This scarce model was produced briefly in 1941 and is the first to carry the small, non-serialized nameplate. The black wrinkle finish on this one is in excellent condition with no chips. The lever stop screws are of the knurled type (on some A400 bugs slotted-head screws are used). This is original and complete, with both weights, except one weight screw is incorrect.
TAC was a WWII Chicago partnership that included Ted McElroy and a couple of his friends. The company made two models of bugs, which were advertised from 1944 through 1946. One was the "hole in the wall" type that came as the model 510 (standard, painted base) and the model 810 (deluxe, with chrome base). The other bug was similar to the Vibroplex Original style, and used a cast base like that on the McElroy P-500. This was offered as the model CP500 (standard, with painted base) and CP800 (deluxe, with chrome base).
TAC also made code practice equipment, continuing the line of Oscillatones with new models (while McElroy in Boston was busy making Morse tape equipment during the war). Tac offered code training equipment to the Signal Corps, incorporating J-38 keys made by others (Lionel and American Radio Hardware).
#TACBOX Signal Corps training set box
This is the wood box, part no. CC350, for the AN/GGQ-1 code practice set made for the Army Signal Corps in 1943. This was made by Telegraph Apparatus Company, a partnership created by Ted McElroy during the war. It contained an oscillator ( Oscillatone ) with a built-in hand key, two spare vacuum tubes (117P7GT OR 117N7GT), wires, and five J-38 keys. A picture of the complete set is shown below.
This is the wood case for the set. It measures about 16-3/4" wide x 8-1/2" deep and 8" high. It has a latch on the front and a carrying handle on the right side.
It is used, there is some paint loss on the left side, and a split in the cover at front left. I have a few, most better than this, same price. Email me.
A great item for the military communications and J-38 or McElroy collector to complete your collection. Note that this is only the case, no other parts are included.
From the manual.
$65.00 (email for shipping cost, with your zip code, may be $20 - $30.)
#907TAC042 TAC model CP500 bug
This was TACs first key; it was advertised in early 1944. Cast into the underside of the base is CP500. The base shape is similar to the previous McElroy P-500.
The design of the pivot frame and damper is a direct copy of the Vibroplex Original. The damper wheel, however, includes a rubber O-ring or bumper (missing on this key, but available at your local hardware store). This is a scarce model; the TAC 510 and 810 (hole-in-the-wall) bugs are more commonly found.
Complete with both weights and in good operating condition. The paddle is chipped (as usual) on the small end, and the main lever stop screw is broken (see photos). The gray wrinkle base finish shows some rubbing. The nameplate is nicely readable but shows some light rust areas.
$195.00 (S&H = $12.00)
McElroy oscillators and other code practice items will be found on the code practice instruments page.
#MACRECORDS McElroy Morse code records.
A scarce, complete unused set of McElroy Electronics Corporation code records. This was the company owned and run by John McElroy, the son of Ted McElroy world's champion radio telegrapher. McElroy Electronics was the successor to McElroy Manufacturing Corp.
These are three, 12-inch, one-sided discs identified as "record set MC-209, code aptitude test." There were undoubtedly made for the U.S. Army Signal Corps. From the size, I believe the records are 78 RPM, and I have not listened to them; I assume they include Morse code.
The records appear to be in excellent, unused condition; the outer package shows age and wear.
Second photo. ... Third photo.
$50.00 (S&H = $7.00)
#MACCAT McElroy catalog.
Catalog from the company founded by Ted McElroy, world's champion radio telegrapher - McElroy Manufacturing Corporation. This catalog is dated 1953 and measures 8-1/2 x 11 inches, has stiff paper covers, and 30 pages, fully illustrated with photographs. It shows and described the company - buildings, machine shop engineers and office personnel... and the telecommunications equipment and products such as ink recorders, paper tape keyers, Wheatstone telegraph tape converters, perforators, and more.
Good condition, complete, unmarked. Several of the pages have dog-ear folds at the bottom corner. A scarce addition to your communications library.
Second photo ... Third photo
$125.00 (S&H = $6.00)
Large McElroy Chart of Codes and Signals. Click on the photo for a larger view.
Ted McElroy, world champion telegrapher during the 1920s and 30s, created his famous Chart of Codes in 1943. It was printed on a cloth backing and measured 25 by 38 inches.
The chart contains codes in five languages, Continental and Morse, Q and Z signals, etc. When first presented at the February 1943 Veteran Wireless Operators of America (VWOA) meet, the Secretary declared it to be "the most complete and authoritative work of its kind that has ever been published."
Today, original charts are rare and often in worn condition. The chart here is a copy of a near-mint chart from our personal collection, professionally reproduced in high resolution on a heavy canvas poster. Our chart is actually 50% heavier than the original and is identical to the original in size and appearance. At over 2 x 3 feet, this is a great display item for the telegraph instrument collector or amateur radio operator.
$119.00 postpaid priority mail in the USA. Due to size foreign shipping must be priority mail, inquire for rate.
Small McElroy chart
As above, but smaller 11 x 17 inch size, printed in full color on heavy paper card stock. Just right to pin to your wall or suitable for framing. Makes a geat gift to a key collector or amateur radio Morse code (CW) operator. Shipped in a heavy mailing tube.
$9.95 postpaid in the USA (foreign shipping add for Canada $3.00, other foreign $6.00)
Original McElroy Chart of Codes and Signals.
812CGY ... An original McElroy chart in very good used condition.
$175.00 ppd priority mail in USA
#MACAUTO McElroy tape reader.
McElroy's famous photoelectric code tape reader. The paper tape, punched Wheatstone fashion with Morse code training messages, would be run through this reader in a Signal Corps radioman's school for teaching the code.
This unit is very clean but lacks the tubes, and does not have the tape reel holder on top where you would normally expect one. Nevertheless, a nice McElroy display item, see all the photos. Second photo. Third photo. Fourth photo.
$50. (S&H = $15.00)
#MACPULLER McElroy tape puller.
One of several machines developed by McElroy for use in the Signal corps radioman's schools during WWII for teaching Morse code. This basic device pulled the code-punched paper tape through a reader.
Lacks the long spring connecting the pulleys (similar to one found on a home film projector), and the nameplate is unreadable. Second photo.
$50. (S&H = $15.00)
Spartan paper tape.
SOLD OUT -- this is for information only.
Paper tape for Wheatstone Morse code perforators such as Kleinschmidt, Creed, Teletype, McElroy and similar perforators. It is oiled paper, 15/32 inch wide; the roll is 8" in diameter with a 2" center hole (I believe each roll is 400 feet). Here is the tape shown on a McElroy head.
This is oiled paper tape and not the plain paper tape designed for RTTY or ink recorders, though it might be OK for display on those machines. For example, it is nearly the same width as the tape used on the TG-34 reader.
For your information, the usual standard sizes of paper tape are:
Perforator tape is oiled paper, 15/32" wide.
5-unit RTTY tape is 11/16" wide, not oiled.
Typical ink recorder tape is 3/8" wide (although some is 5/16" or 15/32") and is not oiled. The TG-34 Signal Corps practice oscillator uses 3/8" tape supplied on 16mm film reels.
Western Union TWX model 33 tape is oiled paper, 1" wide (we may have some of this on this page).
TG-34 inked tape on reel
McElroy 3/8" inked tape on 8-inch 16mm reel. This was used for code practice by the Signal Corps on the McElroy and other automatic keyers such as the TG-10, TG-34, and Long-A-Tone training oscillators.
Note this is the reel of inked tape only, it does not come in a tin can housing, nor do I have empty take-up reels available.
This tape is over 50 years old and is in average used condition, but is good for use or display.
$10.00 (S&H=$9.00 for one reel; inquire if ordering more)
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