Telegraph key is an umbrella term for any switching device used primarily to transmit Morse code characters.

Telegraph key is an umbrella term for any switching device used primarily to transmit Morse code characters.

Such keys are used for all types of manual telegraphy, for example, in electric telegraphy and radio telegraphy.

Telegraph key is an umbrella term for any switching device used primarily to transmit Morse code characters.
Telegraph key is an umbrella term for any switching device used primarily to transmit Morse code characters.
Telegraph key is an umbrella term for any switching device used primarily to transmit Morse code characters.
Telegraph key from the RBM radio set. In the 1950s, it was included in the kit of some R-104 models.

Telegraph key from the RBM radio set. In the 1950s, it was included in the kit of some R-104 models.