Steering wheel interferes the bridge amplifier

Discussion in 'General Electronics Chat' started by ilker06, Jul 9, 2018.

  1. ilker06

    Thread Starter New Member

    Jun 26, 2018
    19
    6
    Hi masters,

    I made a siren and a bridge amplifier for my car and the result is almost perfect except the above mentioned problem.
    When the car is running but not moving, as soon as I start to turn the steering wheel a little buzzing sound comes from the horn speaker.
    When I leave the steering wheel it stops. Probably electric assisted steering wheel system is the reason of the matter.
    I put a 2200 uF between positive and negative terminal of the amplifier and siren. It reduced a little bit but did not remove the buzzing. I put a 1N4007 between positive and negative terminal, the result is the same.
    I don't know do I have to use a coaxial screened cable form amplifier to horn speaker. Can audio output cable catch this kind of noises ?
    What kind of filter do you advice to stop this buzzing ?

    Thanks in advance.
    ilker
     
  2. Hymie

    Active Member

    Mar 30, 2018
    562
    132
    I would recommend you try something as simple as the attached circuit, supplying power to your amp & siren.

    Diode D1 must be rated for the load current, capacitor C1 could be your 2,200uF electrolytic with C2 being a 100nF capacitor.

    Increasing the value of C1 will reduce the 12V line noise further.
     
  3. crutschow

    Expert

    Mar 14, 2008
    20,283
    5,739
    If that doesn't work adequately, you can also try adding a small resistance in series with the diode, perhaps a few ohms, depending upon the current drawn by the siren.
     
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