What's causing hum?

[WORDpictures]

Camcorder is receiving an XLR input from soundboard. Audio is good until a composite output from camera to projectors is connected. This was a temporary set up but would be helpful to know a remedy to allow recording through the camera upon occasion. What might overcome the hum?

[sien]

Is your camcorder running off ac power or the batteries?

[waynehoskins]

Sounds like a ground loop between audio power and video power. The solution is either isolation transformers in the audio line or a humbucker in the video line. Audio transformers are the less expensive solution.

[sien]

Wayne's right. I would recommend the Radial twin iso audio transformer.
http://www.radialeng.com/di-twiniso.htm

[WORDpictures]

Camera was running on electricity. Audio/video had to be recorded separately because of the hum - but like I said, this is temporary & we hope to get approval for some live video production gear soon.