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"The transmitter is a microphone adapted for the transmission of telephone messages and, in general practice, is so used, better results being thus secured than is possible when the transmitter and receiver are identical. In the Blake transmitter, a diagram is supported back of a mouthpiece, as in the Bell telephone."

Blake transmitter

"The transmitter is a microphone adapted for the transmission of telephone messages and, in general…

The Blake transmitter is used in taking voice and transferring it into an electrical signal that can be reproduced by a receiver. Used in telephone systems.

Blake Transmitter

The Blake transmitter is used in taking voice and transferring it into an electrical signal that can…