Remote Audio Relay Kit (Phone Decoder) - South Africa Arduino, Robotics & Electronics Supplier South Africa: R518.22
Leobot Electronics South Africa (Pretoria)
Pretoria, South Africa
Nation-wide delivery or, collect from our premises in Waverley, Pretoria
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Remote Audio Relay Kit (Phone Decoder)
  • Remote Audio Relay Kit (Phone Decoder)
  • Remote Audio Relay Kit (Phone Decoder)

#2876: Remote Audio Relay Kit (Phone Decoder)


This awesome kit includes everything needed, except for the microcontroller of preference, to implement a custom remote audio-controlled set of relays by easily detecting & decoding audio signals (the buttons that the person on the other side is pressing) into numerical values to be used in code. This can easily be used for the development of custom telephone switching boards.



#include <FlexiTimer2.h>
int STD = A0;
int Q1 = A1;
int Q2 = A2;
int Q3 = A3;
int Q4 = A4;
int CH1 = 2;
int CH2 = 3;
int CH3 = 4;
int CH4 = 5;
//Check once every 5 ms
void dtmf_decode(void)
void setup()
void loop()
//Complete the decoding
Decod_finished = 0;
case 1 : Serial.print(" Activate : Channel 1 \n" ); digitalWrite(CH1, LOW);delay(delay_time);digitalWrite(CH1, HIGH); break;
case 2 : Serial.print(" Activate : Channel 2 \n" ); digitalWrite(CH2, LOW);delay(delay_time);digitalWrite(CH2, HIGH);break;
case 3 : Serial.print(" Activate : Channel 3 \n" ); digitalWrite(CH3, LOW);delay(delay_time);digitalWrite(CH3, HIGH); break;
case 4 : Serial.print(" Activate : Channel 4 \n" ); digitalWrite(CH4, LOW); delay(delay_time);digitalWrite(CH4, HIGH);break;
default : Serial.print("Invalid channel \n" ); break;

Product Details

Package Includes
1 PCS  DC5V 4 Channel Relay Board ;
1 PCS MT8870 DTMF decoder module;
1 PCS Male to Male audio wire (3.5mm jack);
Onboard Complex Frequency Decoder IC MT8870DS

DC Power Supply Voltage:4.5V-5.5V(Typical: 5V)

Operating Temperature :-40-+85 °C

IO Drive : Current Maximum 10mA.

PCB Size : 25.4x25.4MM

Product Details

Est. Packaging Size Specifications



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Remote Audio Relay Kit (Phone Decoder)

Regular price: R518.22
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In Stock: 1


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