Memory Backup; Backup Battery Replacement - Yaesu FT-920 Operating Manual

The FT-920's memory data is maintained, even when
DC power it turned off, via a lithium backup battery
with an estimated lifetime of approximately five years.
No data essential to the fundamental operation of the
radio is stored in "volatile" memory, so when the
battery's voltage ultimately is exhausted the trans-
ceiver will not be disabled; you will just observe that
your memories have disappeared.
In some cases of erratic operation, it may be advis-
able to reset the microprocessor to its factory default
condition, so as to determine whether or not a part
failure has caused improper action, as opposed to
some operational error.
This section describes the procedures to be used for
these situations.
FT-920 Operating Manual

Backup Battery Replacement

The backup battery is a standard Sony™ CR2032
(or equivalent), which is installed in a socket on the
bottom side of the transceiver. Replacement of the
battery is easy to accomplish:
Remove the bottom cover of the transceiver (see
page 93).
Locate the backup battery, per the illustration, lo-
cated near the front panel in the vicinity of the bright
silver enclosure on the left side. Remove the origi-
nal backup battery, and replace it with a fresh one
(be sure the replacement battery shows at least 3
Volts on a Voltmeter).
Before closing the case, be certain to check that
you have not accidentally changed the position of
the B switch, located near the backup bat-
ACKUP
tery but immediately adjacent to the above-refer-
enced silver enclosure. This switch must be in the
O position for the backup system to work.
N
Close up the case, replacing the six screws on
the bottom, then tightening the four screws on the
side panels. Be careful not to pinch any wires while
re-assembling the radio.
91