Audiovox MS-306 Owner's Manual page 13

In conclusion, operating these video products
without the engine running will drain the battery
to the point where these products will perform
unacceptably in a short period of time.
Converters
Many RV OEM's incorporate converters as
a source of 12VDC when connected to shore
power (110-120 VAC). Some models put out a
very clean DC supply where others may have a
considerable amount
maximum load.
This AC ripple is filtered by the coach
battery when connected into the circuit, but
when the battery is removed or disconnected the
amount of AC ripple can create major problems
for audio and video products. Noise may result
and the line fuse may fail.
of AC ripple under
Ignition Systems
Unwanted noise generated from the
ignition systems used to be a big problem.
However, with more sophisticated filtering
circuits designed into audio/video products,
these problems are not as wide spread.
Changes in wire harnessing also has
contributed to the decline of application
problems. Use the same ground point for all
related products. This will greatly reduce the
potential for alternator whine.
Audiovox Specialized Applications, LLC
23319 Cooper Drive
Elkhart, IN 46514
Phone: (219) 264-3135
FAX: (219) 264-3007