Vertex VXR-5000 User Manual page 25

delivered to 9-volt regulator IC Q7001
(AN6541) to provide a regulated 9-volt out-
put for repeater circuitry that requires it.
While operating from the AC power, regu-
lated 13.5 VDC is fed through R7004 and
D7002 (188226), providing a trickle charge
for a battery that might be connected.
If
the
AC power source
is
interrupted, the DC cur-
rent from the battery then flows back through
Q7016 (28C2812), RL7001 and DC fuse,
which is now switched (when AC fails) to
bypass R7004 and D7002, and apply full bat-
tery voltage directly to the DC bus.
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Instruction Manual
VXR-5000
2-5