CONNECTING THE AC ADAPTER
The AC adapter must be connected for the System 420 to op- erate.
Note: You must also keep batteries in the system to protect the information stored in memory during power failures.
Cautions:
•You must use an AC adapter that supplies 9 volts DC and at least 50 milliamps. Its center tip must be set to negative, and its plug must correctly fit the system’s DC 9V jack. The supplied adapter meets these specifica- tions. Using an adapter that does not meet these specifi- cations could damage the system or the adapter.
•Always connect the AC adapter to the system before you plug it into the AC outlet, and unplug the adapter from the AC outlet before you unplug it from the system.
Follow these steps to connect the supplied AC adapter.
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