Martin's Autoplex

"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 become obsolete.

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 dits???
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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