5.4Interference with Electronic Equipment

5.4.1Buzzing Sound in Audio Systems

Some inexpensive stereo systems and “boom-boxes” will emit a buzzing sound from their loudspeakers when operating from theAC outlet of Portable Power 250. This is because the power supply in the equipment does not adequately filter the modified sine wave produced by the AC inverter. Unless the stereo can be operated directly from Portable Power 250’s 12-volt DC Power Socket, the only solution is a sound system with a higher quality internal power filter.

5.4.2Television Interference

Portable Power 250’sAC inverter is shielded to minimize interference with TV signals. In some cases, particularly with weak TV signals, some interference may still be visible in the form of scrolling lines across the screen. In this case, take the following corrective measures:

1.Use an extension cord to position Portable Power 250 as far away as possible from the television, antenna and cables.

2.Adjust the orientation of Portable Power 250, television, antenna and cables to minimize interference.

3.Maximize TV signal strength by using a better antenna, and ensure a shielded antenna cable is used.

4.Try a different TV. Different models of TV sets vary greatly in their susceptibility to interference.

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