- 1). Locate the external speaker connections on your transmitters and the receiving connectors on your Dow Key relay. Your Dow Key may only have a single pole double throw (SPDT), in which case you must use the 12 volt DC DPDT (double pole double throw) coil relay to successfully connect your Dow Key relay. If you must connect a DPDT, go to step 2, if not, skip that step and proceed to step 3.
- 2). Connect the one of the contacts of the DPDT to the closed speaker switch of the Dow Key relay. Connect the lead from the FT 101 of your transmitter to the common lead on the relay. Connect the ground lead from the Dow Key relay to the 10 ohm resistor and then connect the resistor to the ground. Hook one side of the DPDT to the negative post of the 12 volt power supply and connect the other through the Dow Key to the positive pole of the power supply. Once this is done, move on to step 4.
- 3). Using the external speaker connections from your transmitter connect one lead to the closed switch to the side of the speaker. Connect the lead from the FT 101 of your transmitter to the common lead on the relay. Connect the remaining lead that will create a contact, when the Dow Key is activated to a 10 ohm resistor that goes to ground.
- 4). Take your 1N400X diode and turn it so the banded end is towards the positive voltage side of the coil and the anode is towards the negative side. This positioning of the diode is the reverse of how the diode would be typically installed. Install the diode right at the relay. This unusual positioning and the location of the diode will eliminate any inductive kick when voltage is removed from the relay.
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