MIDI

DTMF Display LCD with Eight OUTPUTs

Programmable crystal controlled 47 tone CTCSS encoder kit

1.      Programmable crystal controlled CTCSS tone encoder kit

2.      It can encode the 47 CTCSS tones listed below and generates a sign wave.

3.      Output level is fairly flat from 67 to 118Hz at approx. 3V p-p

and then falls gradually to approx. 1V p-p at 254Hz, most

radio’s require less CTCSS input level at higher frequencies

so this is ideal.(10K VR adjust output level range)

4.      There is an encode enable input that connects to the radio's

PTT line (active low). You can tie the encode enable input (PTT) to ground for continuous encode.

5.      Fit the 6 supplied Switch in the following combinations to select the desired tone frequency.A Switch ON is fitted to represent a logic zero (0).

6.      47 CTCSS tones Frequency Accuracy: Guarantee ±0.01%.

7.      It's powered by 7 to 15V DC and draws less them 10 mA.

8.      The product needs to be assembled and soldered by yourself.

9.      PCB size is 40 x 44mm.

Parts list:-

IC                            x1	DIP 14
78L05                     x1	TO-92
Diode 1N4148       x2
10K  Resistor         x3	1/8W
VR 10K                 x1
Crystal 20MHz      x1
100uF or 10uF       x1
20pF or 22pF         x2
0.1uF                     x3	104
0.47uF                   x1	474
0.33uF                   x1	334
PIN Header           x1
DIP Switch           x1	6x2 Pin
PCB                      x1

Fit the 6 supplied DIP Switch in the following combinations to select the desired tone frequency.

Switch ON is fitted to represent a logic zero (0).

Switch  => 654321

Switcch=> 654321

254.1Hz => 000000 250.3Hz => 000001 241.8Hz => 000010 233.6Hz => 000011 229.1Hz => 000100 225.7Hz => 000101 218.1Hz => 000110 210.7Hz => 000111 206.5Hz => 001000 203.5Hz => 001001 199.5Hz => 001010 196.6Hz => 001011 192.8Hz => 001100 189.9Hz => 001101 186.2Hz => 001110 183.5Hz => 001111 179.9Hz => 010000 173.8Hz => 010001 167.9Hz => 010010 162.2Hz => 010011 159.8Hz => 010100 156.7Hz => 010101 151.4Hz => 010110 146.2Hz => 010111 141.3Hz => 011000

136.5Hz => 011001 131.8Hz => 011010 127.3Hz => 011011 123.0Hz => 011100 118.8Hz => 011101 114.8Hz => 011110 110.9Hz => 011111 107.2Hz => 100000 103.5Hz => 100001 100.0Hz => 100010  97.4Hz => 100011  94.8Hz => 100100  91.5Hz => 100101  88.5Hz => 100110  85.4Hz => 100111  82.5Hz => 101000  79.7Hz => 101001  77.0Hz => 101010  74.4Hz => 101011  71.9Hz => 101100  69.3Hz => 101101  67.0Hz => 101110           …….          …….  67.0Hz => 111111