Racal Instruments 9916 Workshop Manual page 24

BATTERY POWER SUPPLY (OPTION)
1 .13 The batteries allow
4~
hours continuous operation from the fully charged
. condition. A 3-position rear panel switch selects ac line power or battery power,
or full rate charging of the batteries from the internal charging circuit. When on battery
operation a warning light indicates when battery voltage is low. To fully charge a
discharged battery requires 14 hours. Avoid overcharging as it will progressively reduce
battery charge capacity. When the instrument is operating from a. c. suppl ies the batteries
receive a trickle charge which can continue indefinitely without detriment to the batteries.
1-3
9916Vol.2