Crown D-150A Service Manual page 5

crown
REVIEW SECTION
I.
Introduction
This
manual
contains
complete service
information
on
the
D-
1
50A.
It is
designed
to
be used
in
conjunction with
the
D-
1
50
A
Instruction
Manual.
However,
some
important information
is
duplicated
in
this
Service
Manual
in
case the Instruction
Manual
is
not readily
available.
NOTE:
THE INFORMATION
IN
THIS
MANUAL
IS
INTENDED FOR
USE BY
AN EXPERIENCED
TECHNICIAN ONLY!
II.
Warranty
As
a
Crown
Warranty Service Station,
you should be
familiar
with
Crown
warranty policies.
Each
Instruction
Manual contains basic
policies
as related to the
customer.
However,
under
questionable
circumstances, please
contact the Technical Service
Department or Director of
Customer
Service
at:
Crown
International, Inc.,
1718
W. Mishawaka
Road,
Elkhart,
IN 46517.
III.
Specifications
General
Specifications
Hum
and
Noise
(20Hz-20KHz):
HOdB
below
rated
output.
Phase Response:
+0, -15°,
DC-20KHz
at
1
watt.
Input
Impedance:
25K ohms, ±3%.
Amplifier
Output
Protection: Short,
mismatch, and
open
circuit
proof.
Limiting
is
instantaneous with
no
flyback
pulses,
thumps, cutouts, etc.
No
premature
limiting
on transients.
Overall Protection:
AC
line
fused.
Thermal switch
in
AC
line
protects against
overheating caused by
insufficient
ventilation.
Controlled
slewing-rate voltage amplifiers
protect
overall
amplifier against
RF
burnouts. Input
overload protection
is
furnished
by
internal resistance
at
inputs of
amp.
DC
Output
Offset
(Shorted Input): 10 millivolts
or
less,
internally
adjustable to
zero.
Turn-On:
Instantaneous, with
minimum
thumps and no
program
delay.
Circuit:
Wideband multiple
feedback loop
design
utilizing
one
linear
IC (dual
op-amp),
total
equivalent of
48
transistors,
22 signal
diodes, 3
zener diodes,
and
6
rectifier
diodes.
Power
Supply: Massive
computer-grade
filter
capacitors
store
over 20 joules
of energy.
Two
regulated
supplies for
complete
isolation
and
stability.
Power
Requirements: Requires
50-400Hz
AC
on
H)0,
200, 220,
or
240V
±10%
operation.
Draws
30 watts or
less
on
idle,
250 watts
at
160 watts total
output.
Heat
Sinking:
The
entire
amplifier
is
used as
a heat
sink.
3/16
inch thick chassis
acts as
a heat sink
along with
auxiliary
fins.
Chassis: All
aluminum construction for
maximum
heat
conduction
and
minimum
weight.
Controls:
Independent
level
controls are
mounted on
the
front panel.
Power switch with associated pilot light
is
on
front panel.
Non-interacting
DC
balance
controls are
mounted on main
PC
board under electronics cover.
A
mono-stereo switch
is
located next to the input jacks
on
the rear panel.
Connectors: Input
-
'A
inch
phone
jacks,
output
-
color
coded binding posts,
AC
line -
3-wire
(grounded) male
connector
on
5
foot
minimum
cable.
Dimensions:
17
inches
(43.18cm) long,
5!4
inches
(13.34cm) high,
8%
inches
(22.23cm)
deep
(from
mounting
surface of front panel), 19
inches
(48.26cm)
long with standard rack
mounting
brackets installed.
Weight: 24 pounds.
Finish:
Satinized
aluminum
front
panel with gray suede
Lexan
insert.