Circuitry Cover; Battery Charger; Batteries - Epson HX-20 Operation Manual

If you turn your HX-20 upside down, you will notice something that
looks like a trap door. This covers the HX-20's internal circuitry.
PLEASE NOTE: You should not remove this cover yourself! Re-
moving it exposes the static-sensitive circuit to possible damage.
Your warranty will become void if you attempt to modify, adjust,
add, or insert any ROM or other part or device in this compartment.
This cover should only be removed by an authorized Epson
dealer or service center and for one of two reasons:
1 ) to install an option ROM.
2.) to select a different character set (see Page 27).
Also, do not operate the HX-20 with the circuit cover removed.
Doing so increases the chance of damage to the circuit, and may
cause the HX-20 to interfere with television or radio reception
nearby.
Your HX-20 comes with a device labelled AC ADAPTER. This unit
is designed to charge the batteries in your HX-20. It is not designed
to run your HX-20 directly
In all cases, you should operate the HX-20 using only its internal
nickel-cadmium batteries.
You may own other electronic products whose accessories
include an AC adapter or a battery charger that looks much like the
HX-20 battery charger. DO NOT USE any of these devices with
your HX-20. Their electrical characteristics will almost certainly be
quite different from those of the HX-20 battery charger. (This is true
even of chargers and adapters rated at 6 volts, and equipped with
AC current.
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