CW Keys and Paddles

For sending Morse code in CW (Continues Wave) mode we use a telegraph key. A Key is a specialized electrical switch used by a trained operator to transmit text messages in telegraph systems, usually in Morse code.

Straight Keys is somehow simple device. It is a simple bar with a knob on top and a contact underneath. When the bar is depressed against spring tension, it forms a circuit and allows electricity to flow. Here is my prime Key (army version 86).

Semi-automatic key or Bug – The original ones were fully mechanical, based on a kind of simple clockwork mechanism, and required no electronic keyer. When the paddle is pressed to the left it makes a continuous contact suitable for sending dashes (or dahs, as most operators call them). When the paddle is pressed to the right, it kicks a horizontal pendulum which then rocks against the contact points, sending a series of short pulses (dits) at a speed which is controlled by the position of the pendulum’s weight. A skilled operator can achieve sending speeds in excess of 40 words per minute with a ‘bug’.

Single Paddle is device which already uses electronics. DIT and DAH are generated electronically. Or you need keyer (electronic device that generates DIT & DAH or does Transceiver)


For more convenient way to send Morse code is paddle. As Single lever Paddle also here is needed to electronically generate DIT & DAH. But here we have two versions:

  • Iambic mode A
  • Iambic mode B
Difference is not when you squeeze  two paddles together – first pressed DIT and then DAH – continues with DIT, DAH, DIT, DAH  or vice versa
Difference is when you release both:
  • Iambic mode A generates: with the last DIT or DAH that it was sending at the time of release.
  • Iambic mode B generates: if it was sending a DAH when you release the paddles, it will add one more DIT.


Learn more from Article  – Using an Iambic Paddle by Chuck Adams, K7QO

Speed comparison is here – counting the keystrokes needed to generate the 26 letters of the alphabet and the ten numbers from zero through nine:

Source iambicmyth.pdf

my DIY versions

My first attempt with MakerBeam constructor + some other materials.

disadvantages – no fine regulations, -> ‘giant’ gap

Not finished. Saw on youtube. Nice but gave up – unable to work with metal..

Simple solution with Limit Switch (used in 3d Printing for mechanical stopend)

Disadvantages : no regulations, -> click gap, hard to hold -> could be improved by making housing for max gap.

Nice copy of Te-Ne-Ke paddle with MakerBeam part.

disadvantages : almost none, just you need to get use it

Mixture of experiences from previous versions

Disadvantages: too short paddles and therefore unflexible

Wooden one made on CNC (Shapeoko 3) – my plan (again)

Disadvantage: Ligth but fine, maybe paddles too short.

3d Printed – source Thingiverse

Disadvantage: Light (needs stronger base), too flexibile (sometimes after DIT also self DAH engaged)