Phone in Hold with Music


Posted on Dec 3, 2012

This circuit will allow you to place a phone call on hold and if you wish to have them listen to music while they are on hold. The circuit operates as follows: The RED wire from the phone jack is typically positive and the GREEN wire is negative or ground. When you want to place a call on hold, close S1 and hang up the handset. The resistor R1 simulates another phone off hook and allows enough current to pass through to prevent the phone company from disconnecting the call. The resistor R2 and LED provide a visual indication that you have someone on hold ( this is optional ) The capacitor C1 and the transformer provide the interface to a radio or CD player headphone jack. Before you hook up the project to the phone line you must determine the polarity of the line.


Phone in Hold with Music
Click here to download the full size of the above Circuit.

Place a voltmeter across the red and green wires of the telephone line, there should be about 48 volts DC positive when the black lead of your meter is connected to the green phone wire. If it is negative 48 volts then reverse the wires.




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    100W Class-A//AB Amplifier
    Agc-with-squelch-control
    Low-Frequency Prescaler
    Continuity Checker
    Speakerphone Adapter Circuit
    tda2822 amplificador de
    Shoo Dog !
    Digital to analog converter using R 2R ladder network and 741 op amp with simulated output waveform
    CB 27MHz Transmitter Circuit
    Schematic of a Breadboard Arduino
    2002 Chevy Cavalier heater/AC temp control wont light up at nite
    Trying to build an Ambilight
    MAGNETOSTRICTION TV REMOTE CONTROL
    Chase circuit loop type lights



    Top