Audiovox AVT-988, Руководство по эксплуатации

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Amperage
A TV will draw considerably more amperage than a VCP. For instance, a 9” TV will draw approximately 3.0 amps
compared to a VCP that draws 1 amp while the tapes are being loaded or ejected.
Checking the voltage of a TV while it is playing shows an approximate 1 volt drop, (11.5 VDC).
The voltage at the VCP can be another .5VDC (11 VDC) less than the TV.
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 of AC ripple under
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 the audio and video products. Noise may
result and often times in line fuses fail.
Ignition Systems
Unwanted noise generated from 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. One rule of thumb is to use
the same ground point for all related products. This will greatly reduce the potential for alternator whine.
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