Keying logic


The keyer uses PIC software developed by Vinicio Coletti IK0WRB (see: ), and uses a 16F84 PIC.

Shown below is the application window that sets the various parameters.

At the start of the call-sign sequence, the carrier is taken 400Hz low for 1 second (set by the 'Pausa iniziale' control). The call sign is then three times (set by 'Ripetizioni msg') at a speed set by the 'Velocita CW' setting. In this case, 10 wpm.
After the call-sign has been sent, the carrier remains low for a further 1 second (set by 'Pausa finale'). The carrier is then returned on-frequency for a period of 45 seconds, as set by 'Durata portante', and the whole cycle repeats.
        keyer1 keyer 2                                                                                                          

Application window


Circuit diagram

keyer 3