must be ventilated to prevent an excessive temperalure rise.
Because transistors are heat sensitive, the 15948 should not
be placed adjacent t o heat-generating equipment or in areas
where
temperature exceeds
I f the 15948 i s installed i n an equipment rack or cabinet
with other heat-producing equipment installed above
below (two or more
or one 15948 with real time
analyzer, oscilloscope, etc.), space must be provided be-
tween the units or the 15948 may become too warm. The
perforated panel
Part No. 10399)
recom-
mended for this purpose. When several amplifiers or
heat-producing units are installed in a single rack or
cabinet, acceptable air temperature may be in
To
determine temperature conditions, operate the system until
temperature stabilizes, then measure air temperature with a
bulb-type thermometer held at the bottom of
upper-
most amplifier. D o not let the thermometer bulb touch
metal because the metal probably will be hotter
the
ambient air. I f air temperature exceeds
i f i t i s a
hot day), the equipment should be spaced farther apart or a
blower should be installed t o ventilate the cabinet.
CAUTION
Do not block the
ventilation holes
when placing other equipment on the
42526 Shelf Mount Cover accessory.
When shelf-mounting the
allow at
least
between the unit and any
wall behind i t to assure air circulation
past the output transistors.
ELECTRICAL
120 Volt,
50160
Hz
Power Connections
Equipment supplied for domestic use is provided with the
power transformer primary strapped for 120 volts (terminals
BATTERY POWER
TERMINAL BOARD
1 t o 2 and
3
to
4
on
The power input nameplate,
adjacent to the power cord on the chassis, i s mounted t o
show the appropriate side specifying the connections (see
Figure 6). Verify that line voltage i s in accordance with the
voltage rating before connecting the
to line power.
240 Volt,
Hz
Power Connections
Export equipment i s provided with the power transformer
primary strapped for 240 volts (terminals 2 to 3 on
The power input nameplate, adjacent to the power cord on
the chassis, i s mounted to show the appropriate side specify-
ing the connections.
For a 15948 previously wired for
ac primary power,
use the following procedure to change wiring for 240V ac,
50160 Hz operation:
Step 1.
Remove four screws securing front panel, open
and lower panel.
Step 2.
Locate terminal board TB3 above power trans.
former
(see Figure
Step 3.
Remove strap "A" connecting terminals 1 and
2 and remove strap
connecting terminals 3
and
4;
solder strap
"C"
t o terminals
and
(see Figure
7).
Step 4.
Remove voltage-rating plate (see Figure
from
chassis, reverse and reinstall to show 240V ac
rating.
Step
5.
Close front panel and secure with four screws
previously removed.
TRANSFORMER
ACCESSORY
FILTER
RECEPTACLE
SWITCH
BATTERY
VOLTAGE
OUTPUT
INPUT
FUSE
RATING
TERMINAL BOARD
TERMINAL BOARD
PLATE
Figure 6. Rear View of 15948 Power Amplifier
