- Pressing the test pushbutton on the front of the transmitter will also cause the transmitter to send a signal
- Each transmission causes the red LED indicator on the front of the transmitter to light, showing that the transmitter is sending a signal and that the battery is in good condition
- One N/O circuit
- Two second transmission
- The D-21 Transmitter contains a timing circuit which is operational each time the transmitter is activated. This timer restricts the transmitters repeatability of operation to a single transmission of a two second duration at approximately fifteen to thirty second intervals. This means that regardless of the number of times the transmitter is activated, it will not send a signal more often than it's time restriction (The D-21 does not repeat it's operation automatically!)
This unit operates 303.875 MHz
New with one year warranty. 9 Volt rectanguler battery not included.
If we are out of these please contact us, we have one additonal one left that is not new.
Product Code: D-21-303.875
