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Components for DTMF


i. Semiconductor


 IC1                                                                                  KT3170 DTMF Decoder


 IC2                                                                                  74LS154 4-to-16 line



IC3-IC4                                                                           74LS04 hex Inverter


IC5-IC9                                                                           74LS74 D type flip/flop


T1-T10                                                                               BC547 Transistor


D1-D10                                                                                    1N4007


ii. Resistors


R1-R2                                                                                       22k


R3                                                                                             220W


R4                                                                                             10k


R5                                                                                             1M


R6                                                                                             330k


R7-R16                                                                                     2.2k



iii. Capacitors


C1                                                                                               0.1


C2                                                                                              0.01


iv. Miscellaneous


X TAL                                                                               3.58 MHz Crystal



              12V, 200W, 1C/O Relay