Noise In A/V Systems - PROCEED PRE User Manual

channels cannot be changed by the PRE while in "ssp" mode, the preamplifier
cannot corrupt the careful calibration of the processor's output levels. And
since the video sources would be fed directly to the processor's audio input(s)
at a line level, input calibration cannot be disturbed by the preamplifier.
In some cases, connecting your audio and video systems together in this fash-

Noise in A/V systems

ion can result in noise, typically a 60 Hz or 120 Hz hum. The most common
cause for this noise is a "ground loop" caused by the presence of two ground
references in the system: one from the power company and another from the
cable-television company. The simplest way of solving this problem is to
break the cable company's ground by using a 75Ω-75Ω balans (isolation)
transformer on the incoming cable line, before it reaches your television or
VCR. Contact your Proceed dealer for assistance.
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