There are a few projects kicking around the internet which make for quite a good starting point. Also, if you’re on a very tight budget, you could save yourself a bit of money building your own. It’s a great product, but in the event that you find something you don’t like about its functionality, there’s not a lot you can do about it, because it’s not an open source product.

The control signal for it will be again given by the CM8870 IC to drive the motor while checking the mobile data.A few months ago, Matt purchased a Rotatone pulse to tone module for one of his vintage telephones. The next section is the motor driver circuitry. The Kit Consists Of a Decoder Interface Circuit that consists of the RC combination acting as a tone filter which gives the filtered signal to DTMF decoder IC CM8870 which decodes the frequency to give a 4-bit binary output. The system can be used in two ways that directly connect a mobile (through headphones) to the decoder to the control operation at a location or make a call to the remote location mobile connected to the decoder to control the operation. This tone can be received through the DTMF receiver and decoded to generate a binary 4-bit sequence that is directly compatible with digital controllers. In this Kit DTMF Robot tone is transmitted over the remote location and can be heard at the remote location using the mobile communication protocol. The phone is technically a DTMF generator that produces DTMF tones as you press the buttons. DTMF is the generic term for Touch-Tone (touchtone is a registered trademark of ATT).

The DTMF Robot kit DTMF stands for Dual Tone Multi-Frequency, it is the foundation of your phone system.

Dtmf converter