radio interference on a hardwire

Discussion in 'Media Production' started by envisaging, Feb 17, 2008.

  1. envisaging

    envisaging Guest

    I just encountered a problem on set where I was getting a very loud radio station on a hardwired microphone.

    Any clues on how to avoid in the future?
     
  2. for-a-song

    for-a-song Guest

    All. your cables balanced and shielded? Maybe a pin 1 prob in a piece of gear or look for any other lines running close your your connectors.

    Could try to throw a line conditioner in front of your gear as well or maybe some iso plugs.

    Hope this helps.
     
  3. Boswell

    Boswell Moderator Has Studio Services

    Joined:
    Apr 19, 2006
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    Location:
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    A while back I made a set of in-line XLR interference suppressors for just this sort of problem. I haven't got one here at the moment to look inside, but if I remember correctly I put series absorption ferrites at the signal input and common-mode ferrites at the output. Between the two sets of ferrites were delta capacitors to shunt residual r.f. to ground (shell, not pin 1). Since making the suppressors, I have never encountered an r.f. problem that they did not knock on the head.

    Something to check first, though, is that XLR pin 1 on the microphone does actually connect to the microphone body and that pin 1 really is grounded at the pre-amp.
     
  4. bent

    bent Guest

    Did you try simply swapping the cable?

    Sometimes the easiest fixes are the most often overlooked.