Historical information

A telegraph key or Morse key is a specialised electrical switch used by a trained operator to transmit text messages in Morse code in a telegraphy system. Keys are used in all forms of electrical telegraph systems, including landline (also called wire) telegraphy and radio (also called wireless) telegraphy. An operator uses the telegraph key to send electrical pulses of two different lengths: short pulses, called dots or dits, and longer pulses, called dashes or dahs. These pulses encode the letters and other characters that spell out the message.

Physical description

Metal device with black knob mounted on a wooden base. A plaque with printed text is also attached to the base.

Inscriptions & markings

Printed: GIVE A SERIES OF DASHES INSTEAD / OF A STEADY EXPOSURE WHEN CALL- / ING FOR LIGHT, OR SHOWING LIGHT. / USE THE PLUG IN No. 1 / SOCKET AS LONG AS THE / LIGHT IS GOOD ENOUGH. / THEN CHANGE TO No. 2 THIS WILL / LENGTHEN THE LIFE OF BOTH BULB / AND BATTERY.