This kit decodes all DTMF tones including 0-9,#,* , A-D. Can use any source for the DTMF tone, such as Phone line, Scanner, etc. When you press the "Learn" button the internal uController stores the DTMF code sequence (up to 16 Digits) in non-volatile memory. When this code sequence is detected the unit activates the internal relay. To deactivate you simply enter # and your code or press the Reset button on the unit. Ideal for controlling a light, air conditioner, etc. from a remote location. Can be used to disconnect the Phone line if a certain number is Dialed. RJ-11 Mod jack for phone line connection, DIN connector for relay output. AC adaptor supplied. DTMF-1