Arduino DTMF Shield

The Arduino DTMF Shield is a dual-tone multi-frequency decoder module that lets your Arduino interpret touch-tone signals from phones. Connect it to a GSM/GPRS shield and you can send commands to your Arduino via phone call — press buttons on your phone to control motors, lights, or any connected device remotely.

The shield features an audio connector for input, a speaker connector for audio monitoring, and a microphone connector for over-the-air reception. Combined with a GSM shield, it enables wireless command and control from any phone worldwide within GSM range.

Key Features

• DTMF Decoding – Decode touch-tone signals from landline or mobile phones
• Audio Input Jack – Connect to audio sources or GSM shields
• Speaker Connector – Monitor incoming audio signals
• Microphone Connector – Over-the-air DTMF reception (best with filtering)
• Arduino Shield Format – Stacks directly onto Arduino boards

Specifications

• Dimensions: 37×37×9mm

Ideal For

• Remote control via phone calls (with GSM shield)
• Telephone-activated automation systems
• DTMF-based security access codes
• Audio command decoding for robotics

Package Contents

• 1× DTMF decoder module

Resources

• Wiki Documentation & Tutorial
• Arduino Library & Examples (ZIP)