ground loop issues can be major pains!!

Senator Mike Michaels, c.a.s.
Studio M Productions
Senator@...
Sound for Film, Video, Radio, TV and PA
----- Original Message -----
From: pverrando
To: Lectro@yahoogroups.com
Sent: Tuesday, July 07, 2009 7:47 AM
Subject: [Lectro] Re: DC offset issues with UCR211's powered by M4MKII mixer





Thanks for the info!
Lifting the ground at either end of the audio cable did not work. I tried
strapping pin 1 to the connector shells on the cables. The contact of the female
shell with the receivers xlr jack is not tight enough to ensure positive
contact. Plus the inside of the jack is painted and would have to be completely
sanded to the bare metal.

I wonder if the same ground issue could exist if the receivers were on the
back of a camera and taking power from the cameras 12 volt accessory jack. I
will have to listen for the hiss from now on to insure it does not. I always
listen to an RF hop before shooting begins anyway. As you suggest, if I do the
internal strap and find that some other mixing console or camera doesn't 'like'
it, it would be difficult to remove the strap quickly.

Before I figured out the ground loop issue, I had sent one of these receivers
in for service because of the hiss. The tech was unable to duplicate the problem
on the bench, for obvious reasons.

Thanks again!
Pete Verrando





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