connecting my tiny FM radio to external speaker

Discussion in 'General Electronics Chat' started by mrinal81, Aug 2, 2010.

  1. mrinal81

    Thread Starter New Member

    Jun 10, 2010
    I have a tiny FM radio(made by Philips). It has only a 3.5 mm jack and no speaker. It works well with a headphone. I try to connect it to my PC speakers but it does not works. what should be done to connect it to an external speaker? please help.
  2. Potato Pudding

    Well-Known Member

    Jun 11, 2010
    Small headsets are high impedance output devices probably more than 32Ω and often more than 120Ω. For max power coupling the amplifier wants to match that impedance. Max power coupling is pretty important becasue for headsets we are talking milliwatts of power.

    Your Computer speakers might be 8Ω. Because the FM radio is High Impedance most of its potential output power will be lost internally trying to drive the low impedance load.

    If your computer speakers are amplified they might also have a threshold problem. They could be biased to damp out low signal levels in order to prevent hissing noises, and unintended radio detection problems.

    How badly do you need this to work?
  3. kingdano


    Apr 14, 2010
    you should look into small headphone jack speakers which do not require power externally.

    i used to have a pair when i was a little kid.

    no volume control, but a good sound boost.