A knocker kit that will drive single external solenoid to “knock” on doors, tables or anything. A range of different cadences are available selectable by the ‘prog’ button. The selected knocking cadence is saved even when power is removed so once setup it stays doing the same knock.
The knocker kit has plenty of drive capability for the many voltages and currents of solenoids that are available (6-12V and up to 2A) and an ideal solenoid can be purchased from this site (see below). The circuit can have low quiescent (standby) current if driven from a separate 6V supply , making the board suitable for running from batteries. Provision is provided for a door bell cable connection to trigger knocking and a test button is provided for an easy test of the board and solenoid connections.
Solenoids need to be purchased separately – see below.
This Kit Contains small parts and is therefore not suitable for children under 5 years old.