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Components for DTMF

 

i. Semiconductor

 

 IC1                                                                                  KT3170 DTMF Decoder

 

 IC2                                                                                  74LS154 4-to-16 line

                                                                                          decoder/demultiplexer

 

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

 

RL1-RL10                                                        

              12V, 200W, 1C/O Relay