TKIE - Using the loudspeaker as microphone

This article describes how the loudspeaker connected to a TKIE-2 kit also can be used as a microphone.

Wiring diagram

Wiring diagram - The two relays are used to switch between mic input and amplifier output

Use a 100pF capacitor in series with the plus-wire to remove the microphone bias

ICX/AlphaCom configuration

The relays of the TKIE switches the loudspeaker. In idle the loudspeaker is connected to the mic input (idle). When the relay is activated the loudspeaker is connected to the amplifier output.

To operate the relays, an event must be created with the TKIE-2 kit as the Event Owner:

The Audio event is used to switch the relays

In the example above the relays are controlled by the SET_IPRCO command. One can alternatively use the RCO command.