William O. Coffe of Cleveland patented a mechanical semi-automatic key with a vertical pendulum on January 11, 1904. However, he made and sold a number of Mecographs in several different versions with horizontal pendulums. The Vibroplex did help telegraphers avoid RMD, but it also helped them send faster, which meant they earned more money, since telegraphers were generally paid by the word. Within about ten years, the Vibroplex and a number of clones made by others became very popular. The Vibroplex Company has made a variety of bugs during its long history.
Some models are unusual, some are scarce, and some are common.
Several other manufacturers made clones and copies of Vibroplexes, some legal and some illegal. Some of the people involved are interesting and colorful, including Martin himself and J. E. Albright, who ran the company for more than forty years, many of them spent in court defending his product.