Keyer Coupler

A Keyer Coupler, also known as a keying coupler or keying interface, is a device used in amateur radio or telegraphy to connect a key or paddle to a transmitter. It is used to convert the mechanical action of pressing a key or paddle into an electrical signal that can be used to control the transmission of Morse code or other digital modes.

The keyer coupler typically consists of a set of input terminals where the key or paddle is connected, and an output terminal that is connected to the transmitter's keying input. It may also have additional features such as adjustable keying speed, keyer mode selection, and keying waveform shaping.

When the key or paddle is pressed, the keyer coupler detects the action and generates an electrical signal that is sent to the transmitter. This signal typically consists of a series of on-off keying (OOK) pulses, where the duration of the on and off periods corresponds to the timing of the Morse code characters being transmitted.

Keyer couplers are commonly used in amateur radio stations for Morse code operation, as well as in some digital modes where keying is required. They provide a convenient and reliable way to interface a key or paddle with a transmitter, allowing the operator to easily send Morse code or other digital signals.