"Only a few of the keys have been made thus far, but
without exception every man fortunate enough to have secured one will attest
its worth." --The Railroad Telegrapher, May 1904
Martin's Autoplex, made by the United Electrical Manufacturing Company
in New York, was the direct predecessor of the Vibroplex line. It was
the result of Martin's patent no. 732,648 in 1903. Except for the nagging
problem of William O. Coffe and the Coffe Mecograph, the Autoplex and then
Vibroplex would have had a virtual lock on the telegrapher's need for a
semiautomatic key. The Autoplex made both dots and dashes by means of
an electromagnet. Dashes were not just a simple contact closure. The mechanism
was complex and the instrument was likely difficult to assemble and adjust
properly. Clearly, the flat spring used in the Vibroplex to form repetitive
dots was far superior and it only took a few years for the Autoplex to
There seems to be general agreement with Doug Seneker's division
of Autoplex production into three models. The first production model circa
1902 was on a wooden base and laid out horizontally. The second model, made
between 1903 and 1905 was on a metal base and had some components placed
above the coils. The third and last model about 1905, is shown here. It
is the most compact of the Autoplex models and is built on a square metal
base. It has conventional thumb and finger pieces on a single lever.
The keys in The Sparks Telegraph Key Review get rotated into the operating
position of a modern HF rig for "exercise." This one's tough to handle
on the air!
This is an elementary series vibrating bell. The trick to it is
that when the electromagnet pulls the contact away from the contact post,
the circuit is broken and the magnet is demagnetized. A spring,
not shown in the diagram, pulls the armature back to its original
position. Adapted from Hawkins Electrical Guide #8, 1917.
For those of you telegraph aficionados who don't think this is relevant
here...just how do you think Martin's Autoplex makes those repeating
Click on the button and hold it down to set the bell in motion!
It may take a few moments for the sound file to load...
Who Are These Dudes?
One of these men is the notorious Abraham White. He was actually born
with the name Abraham Black, but changed it probably for a better image
with his clients, whom he bilked of millions of dollars. He sold nearly
worthless DeForest Company stock to any willing buyer and eventually went
to jail. One of these men is Horace Martin, the inventor of the Vibroplex
bug, the most popular semiautomatic telegraph key in history. Another of
these men is Les Logan, who at one time made the Speed-X Hi-Speed Key.
And one of these men is Ted McElroy, who made the famous Mac Keys and who
could copy over 75 wpm. Which is which? Click the pictures to find out!
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