The Telegraph Office
A Photographic Reference for Wire and Wireless Telegraph Key
by Neal McEwen, K5RW
Last Updated 16 August 2004
Copyright © 1996 - 2004 Neal McEwen
Office Main Page | Wireless
Gallery | On-Line
The Photo Gallery consists of photos of telegraph keys, bugs,
and related wire and wireless telegraph artifacts for identification
reference purposes. Where known, the maker and approximate date
manufacture are given to assist in identifying similar items.
All photos are copyrighted. Non-profit organizations and
may link to them, given proper recognition to The Telegraph
Those parties with pecuniary interests must seek permission to use.
Table of Contents
-- Spark keys typically carried the high voltage and high current of
primary of the spark transformer. Spark technology was largely gone by
the early 1920s.
Radiotelegraph keys --Radiotelegraph
keys were used with CW transmitters and were usually in the cathode
or keyed a low level stage. They did not need the voltage and current
of the spark key.
-- Horace Martin introduced the semi-automatic
'bug' as it is more commonly called in, 1905. Many worked around the
patents with their own design, while other copied the design in
of the patents.
Pre-1925 Martin -
Bugs -- Horace Martin introduced many
models during this period. This section
Much more to come!
Pre-1930 Bugs --
Making bugs was a profitable endeavor; many makers joined in, some with
their own unique features.
L. Boulter: c. 1914. Predecessor of the Vibroplex Lightning bug.
'Dinger': c. 1909. Made in Cleveland. Very unusual. Tension
on pendulum adjusted like a telegraph relay.
- Mecograph right angle bugs
- A-to-Z bugs made by the A-to-Z Electric Novelty
in blatant violation of Martin Vibroplex patents.
Telegraphic Transmitter Co. Auto-Dot bug: c. 1912. Notice the
bug: c. 1912. Windup bug; from the Wm. Sutter Collection, very rare.
c. 1910. Vertical dot maker for hand key; from the Wm. Sutter
Thomas bug: c. 1910. An illegal Vibroplex clone. Very uncommon.
- Dunnduplex bugs, made by Thomas J. Dunn of New York.
on top for alternate means of making dots and dashes.
bug: c. 1912. Sold by Van D. Liggett of Tyler Texas.
an A-to-Z bug re-labeled. Resembles the Martin 'X-model.'
More makers entered the market, many targeting radiotelegraph
World Champion code operator Ted McElroy was one of them.
bug: by the Ultimate Transmitter Co: c. 1925. Designed for
telegraphers. Shown with adjusting tools and wedge.
1928. Made by Electro Mfg. Co. of San Francisco and Fresno, California.
The electromagnet was in series with the telegraph line and helped to
Jr.: c 1928. This is the same Electro-Bug without the magnet and
made for the amateur radio market.
- Bunnell Gold Bug made by J.H. Bunnell of New York.
was very attractive but very poor handling. They were difficult to sell
and some were even given away by a radio house with a $15 order. About
1200 were made.
Electric 'Sematic': c. 1928. Combination bug and sideswiper. Only
ever made by Signal Electric.
'Triplex': c. 1922. Right hand bug, left hand bug and hand key made
by Precision Thermometer and Instrument Co. of Philadelphia.
view: Note symmetry of dot and dash parts.
post - 1940 Bugs
The last days of the bug before the popularity of electronic keyers and
the disappearance of American Morse landline telegraphy.
- McElroy Bugs -- Made by the Worlds Champion Radio
T. R. McElroy in Boston.
- Standard Radio Bugs Very heavy duty bugs most likely
1930s. Came with japanned, red, green and chrome bases.
c. early 1930s. First or four Go-Devil models by Al Emory. About 400
bug: c. late 1930s. Made and sold by Radio Shack of Boston. (Not
bug: Model 501, c. 1939. Made by Les Logan.
Metal Stamping Co.: c. late 1930s. BMS also made as J-36 for the
Rapids bug: 'Professional' model, c. late 30s to 50s. Only bug ever
sold in kit form. $2.97 post paid in 1939! Made by Electric Specialty
of Cedar Rapids, Iowa.
"Blue Racer": c. 1938. Used by a sparks on Cities Service oil
Military Bugs --
W.W. II created a demand for more bugs and keys than could be produced
normally. Lionel (of toy train fame) and others filled in.
- Dow-Key bugs, made by the same people who made
'Valiant': c. 1939 - 1950. Fully Automatic bug. Dual Pendulum,...
for dots and one for dashes. Only several hundred made by Melvin E.
view: There are 17 adjustments on this bug!
- Telegraph Apparatus Co. (TACo.) bugs. This was
plant and second go at making keys.
c. 1944. Note Vibroplex like construction and hollow base
c. 1945. Commonly called 'hole-in-the-wall' design. Many of these bugs
of label: Note 'not incorporated.' All TACo bugs had this.
c. 1945. The Chrome based version of the 510.
c. 1951. Limited production right angle bug by Breedlove. Beautifully
and handles very well.
Apex: prototype with engineering drawings, c. 1963. Dwight Hunter
an old time commercial sparks.
'model-U': c. 1958. A combination bug and sideswiper. The last
model made by Al Emory. Very Uncommon.
- Bunnell-Martin bugs, a marriage of J. H. Bunnell and
pre -1915 Landline Keys
-- These keys were used to send American Morse
iron or copper wires. Typically the current through the contacts was
than a tenth of on ampere.
KOBs -- KOB
is an early abbreviation
Key on Board. Usually this refers to a key and sounder or a key and a
relay on a single board.
Sounders and Resonators
-- Sounders are electromechanical devices that
dot and dash sounds for landline American Morse operators. Resonators
or directed the sound; they were especially useful in large offices so
an operator could here the correct 'wire.'
Pocket Test Sets
test sets were used by line walkers and repairmen. They were also used
by trainmen to report the position of an off schedule train.
Relays, Repeaters and
-- Relays and repeaters were electromechanical
used to boost weak signals on land lines. Registers were very early
used to copy American Morse code before the sounder was invented. Dots
and dashes were traced onto a moving paper and later transcribed into a
-- The first telegraph cable between Europe and North America was laid
Pegboards and Switches
-- Pegboards are the telegraph equivalent of a
Code Learning Instruments
-- Many schemes were devised to automate the
of both codes, American Morse code and International, sometimes call
-- Early transmitting and receiving equipment was
of individual components, often very well made and attractive.
Telegraph and Wireless Services
- United States Army Signal Corps. bugs. The J-36 was
in the mid 1930s. Listed here in order of numbers made.
J-36: c. 1943. Serial number 004074. Lionel's clone of a 'Lightning
J-36: c. 1942. Serial number 59. A 'Lightning Bug' with a Signal
J-36: c. 1942. Serial number 2036. Similar to Bunnell-Martin 'Flash
Metal Stamping Co.: c. 1936. One of the first J-36s and a unique
G. Martin 'Rotoplex': c . 1943. Serial number 21. Made by James
Jr. Electric Co. of Louisville, Kentucky. An Army Airways
SA-100: c. W.W.II. A right hand and left hand bug used by Royal
Air Force. The rubber feet on top of the bug allow it to be turned
down for lefties. Note resemblance to Logan SPEED-X bugs.
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