13 |
P a ge
(Relay
Shown
in
Non
‐
Alarm
Condition)
VARIABLE
STEP
ATTENUATOR
BDA
gain
can
be
reduced
by
up
to
30
dB
in
2
dB
steps
using
the
variable
step
attenuator.
Gain
adjustment
is
made
with
rotary
switches
accessible
via
the
access
door
of
the
BDA
enclosure.
Arrows
on
the
shafts
of
these
switches
point
to
the
value
of
attenuation
selected.
BDA
gain
can
be
determined
by
subtracting
the
attenuation
value
from
the
gain
reported
on
the
BDA
Test
Data
Sheet
for
that
side
of
the
unit.
The
attenuators
are
labeled
for
Uplink
and
Downlink.
(Figure
3a)
Conditions
for
DC
Backup
Alarm
The
alarm
monitors
the
AC
power.
If
the
AC
power
fails
and
DC
is
connected,
the
DC
Alarm
LED
will
indicate
DC
power
is
drawn.
