Ringing with External Mic

[LifeChronicles]

I am having an issue when I use an external microphone with my Sony PD-170 Camcorder. When it is connected, it has no buzz, and sounds fine. But accompanying the audio I hear through my headphones (or on the tape, afterward), there is a ringing or buzzing sound that rises and falls with the audio.

I have switched the XLR cables that connect the microphone to the camera. I have fiddled with the connection, and it seems stable. I have tried turning the camera audio up and down. I have made sure that the microphone is in its proper stand, so that it picks up no extra vibration.

Does anyone have any thoughts on what could cause this?

[edDV]

I am having an issue when I use an external microphone with my Sony PD-170 Camcorder. When it is connected, it has no buzz, and sounds fine. But accompanying the audio I hear through my headphones (or on the tape, afterward), there is a ringing or buzzing sound that rises and falls with the audio.

I have switched the XLR cables that connect the microphone to the camera. I have fiddled with the connection, and it seems stable. I have tried turning the camera audio up and down. I have made sure that the microphone is in its proper stand, so that it picks up no extra vibration.

Does anyone have any thoughts on what could cause this?

What mic are you using? Are you sure the mic isn't generating the noise? (e.g. when plugged into an amp?)

Is the PD170 set to AGC=OFF ? (see P-53 in manual).
AGC will drive gain up when sound is quiet. This will amp up any small line noise. Best to use manual level set to loudest expected audio during mic check.

[Bonie81]

@LifeChronicles
Hope you are using mic for in-door recording. Some professional mics are immune to some noise level upto certain extent. But, there are lots of other techniques to calibrate mic properly prior to actual recording.
as said by edDV

AGC will drive gain up when sound is quiet. This will amp up any small line noise. Best to use manual level set to loudest expected audio during mic check.

Properly calibrate mic will sound and record same as mic test 1...2...and 3.... and intial short tune.
Hope this link : Reduce Noise in an Audio Recording will give just some basic information.

I am still fumbling to reduce Wind-Noise in out-door recording in spite of using noise-canceling outdoor microphone.