Crown D-150A User manual

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SERVICE MANUAL
D-150A POWER AMPLIFIER
CROWN INTERNATIONAL, INC. 1718 W. MISHAWAKA RD. ELKHART, INDIANA 46517
©1988 Crown International, Inc.
K30028-2
1/83

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RVW Sec.
Section 6
Section 7
Section 8
TABLE OF CONTENTS
Review
I. Introduction .......
II. Warranty
III. Specifications .....
IV. Panel Configuration
V. Performance Graphs
Illustrated Parts List
6.1 General Information
6.2 Standard and Special Parts
6.3 Ordering Parts
6.4 Shipment
6.5 Terms
6.6 Schematics/ Parts Lists/ Exploded View Drawings
Maintenance
7.1 Introduction
7.2 Required Test Equipment
7.3 Soldering Techniques
7.4 Basic Troubleshooting
7.5 Discharging Instructions
7.6 Disassembly for Inspection, Service, Testing, Adjustment and Repairs
7.7 Reassembly
7.8 Electrical Checkout and Adjustment Procedures
7.9 Troubleshooting Hints
7.10 Voltage Conversion Chart
7.11 Block Diagram Circuit Theory
7.12 Theory of Operation
Service Bulletins
6-1
6-1
6-1
6-1
6-1
6-2
.7-1
.7-1
.7-2
.7-7
.7-8
.7-8
7-10
7-10
7-12
7-15
7-16
7-17
.8-1

LIST OF ILLUSTRATIONS
Fig. RVW.l
Fig. RVW.2
Fig. RVW.3
Fig. RVW.4
Fig. RVW.5
Fig. RVW.6
Fig. RVW.7
Fig. RVW.8
Fig. RVW.9
Fig. RVW.10
Fig. RVW.l 1
Fig. 6.1
Fig. 6.2
Fig. 6.3
Fig. 6.4
Fig. 6.5
Fig. 6.6
Fig. 6.7
Fig. 6.8
Fig. 6.9
Fig. 6.10
Fig. 6. 1
1
Fig. 6.12
Fig. 6.13
Fig. 6.14
Fig. 6.15
Fig. 6.16
Fig. 6.17
Fig. 6.18
Fig. 6.19
Fig. 7.1
Fig. 7.2
Fig. 7.3
Fig. 7.4
Fig. 7.5
Fig. 7.6
Fig. 7.7
Fig. 7.8
Fig. 7.9
Fig. 7.10
Fig. 7. 1
1
Fig. 7.12
Fig. 7.13
Fig. 7. 14
Fig. 7.15
Fig. 7.16
Fig. 7.17
Fig. 7.18
Fig. 7.19
Fig. 7.20
Fig. 7.21
Fig. 7.22
Fig. 7.23
Fig. 7.24
Fig. 7.25
Fig. 7.26
Fig. 7.27
Fig. 7.28
D-150A Front Panel
D-150A Rear Panel
Nominal Frequency Response .........
Nominal Phase Response .............
Nominal Crosstalk
Nominal Noise Sepectrum
Nominal Output Impedance
Nominal Output Phase Angle
Nominal Damping Factor (8 ohms) ....
Nominal Power Efficiency ............
V-I Plot
MI-261 Main Board Schematic
MI-261 Foil Board Layout
MI-261 AMain Board Schematic ......
MI-261 AFoil Board Layout ..........
MI-261 BMain Board Schematic
.
MI-261 BFoil Board Layout
MI-26 1C Main Board Schematic
MI-26 1C Foil Board Layout
MI-261 DMain Board Schematic
MI-261 DFoil Board
MI-261 EMain Board Schematic
MI-26 IE Component Board Layout
MI-261 EFoil Board Layout
IOC Component Board Layout
IOC Foil Board Layout
Front Panel Assembly
Chassis Assembly
Output Assembly
Miscellaneous Assembly
Miniature Soldering Iron
Correct and Incorrect Solder Application
Unsoldered Wire
External Strands
Cut Strands
Wire Strippers
Disturbed Joint
Cold Solder Joint
Rosin Joint
Component Lead Spacing
Component Lead Bending
Correct Pressure Applied
Acceptable Solder Joints
Soldering to aLug
Turret Terminal ......................
Wire Braid Desoldering ...............
Discharge Points
IM Distortion Test Set-up
Signal to Noise Test Set-up ............
Voltage Conversion ...
D-150A Block Diagram
Input Stage
Voltage Amplification Stage
Output Stage
Protection Circuitry Stage
Bootstrap Supply
IOC Stage
World-Wide Voltage Map ..... ....
.R-3
.R-3
.R-4
.R-4
.R-5
.R-6
.R-6
.R-6
.R-7
.R-7
.R-8
..6-2
..6-2
..6-4
..6-5
..6-6
..6-7
..6-8
..6-9
.6-10
.6-11
.6-12
.6-12
,6-13
.6-13
.6-13
,6-16
6-17
6-
19
6-21
.7-2
.7-3
.7-3
.7-4
.7-4
.7-4
.7-5
.7-5
.7-6
.7-6
.7-6
.7-6
.7-6
.7-7
.7-7
.7-7
.7-8
7-
11
7-12
7-15
7-16
7-17
7-17
7-18
7-18
7-19
7-19
7-20

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REVIEW SECTION
I. Introduction
This manual contains complete service information on
the D- 150A. It is designed to be used in conjunction with
the D- 150AInstruction 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 aCrown 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 1watt.
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, 3zener 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 aheat sink.
3/16 inch thick chassis acts as aheat 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 5foot 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.

Stereo Specifications
Output Power: 80 watts per channel minimum RMS
(both channels operating) into an 8ohm load over a
bandwidth of 1Hz-20KHz at arated RMS sum total
harmonic distortion of 0.05% of the fundamental output
voltage.
Frequency Response: ±0. 1dBDC-20KHzat 1watt into 8
ohms; ±ldB DC-lOOKHz.
IKHz Power: 90 watts RMS into 8ohms, per channel,
both channels operating, 0. 1% total harmonic distortion.
Harmonic Distortion: Less than 0.001% from 20-400 Hz
and increasing linearly to 0.05% at 20KHz at 80 watts
RMS per channel into 8ohms.
LM, Distortion S.M.P.T.E. (60Hz-7KHz 4:1): Less than
0.05% from 0.01 watt to 0.25 watts and less than 0.01%
from 0.25 watts to 80 watts into 8ohms, per channel.
Slewing Rate: 6volts per microsecond (slewing rate is
the maximum value of the first derivative of the output
signal, or the maximum slope of the output signal).
Damping Factor: Greater than 400, DC-400Hz into 8
ohms.
Output Impedance: Less than 15 milliohms in series with
less than 3microhenries.
Load Impedance: Rated for 8ohm usage; safely drives
any load including completely reactive loads.
Voltage Gain: 20.6 ±2% or 26.3±2dB at maximum gain.
Input Sensitivity: 1.19 volts ±2% for 80 watts into 8
ohms.
Output Signal: Unbalanced, dual channel.
Monaural Specifications
Output Power: 160 watts minimum RMSintoa 16ohm
load over abandwidth of lHz-20KHz at arated RMS
sum total harmonic distortion of 0.05% of the
fundamental output voltage.
Frequency Response (IKHz Power): ±0.15dB DC-
20KHz at 1watt into 16 ohms; ±ldB DC-60KHz, 180
watts RMS into 16 ohms.
Harmonic Distortion: Less than 0.001% from 20-400Hz
and increasing linearly to 0.05% at 20KHz at 160 watts
into 16 ohms.
LM. Distortion S.M.P.T.E. (60Hz-7KHz 4:1): Less than
0.05% from 0.01 watts to 0.25 watts and less than 0.01%
from 0.25 watts to 160 watts into 16 ohms, per channel.
Slewing rate: 12 volts per microsecond.
Damping Factor: Greater than 400, DC-400Hz into 16
ohms.
Output Impedance: Less than 30 milliohms in series with
less than 6microhenries.
Load Impedance: Rated for 16 ohm usage; safely drives
any load including completely reactive loads.
Voltage Gain: 41.2 ±2% for 160 watts into 16 ohms.
Input Sensitivity: 1.19 volts ±2% for 160 watts into 16
ohms.
Output Signal: Balanced, single channel.
R-2

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Fig. RVW.l D-150A Front Panel
A,
B.
c.
D.
E.
CHANNEL 1IOC INDICATOR
CHANNEL 2IOC INDICATOR
CHANNEL 1INPUT LEVEL CONTROL
CHANNEL 2INPUT LEVEL CONTROL
ON/OFF SWITCH
Fig. RVW.2 D-150A Rear Panel
F. MONO/STEREO SWITCH
G. CHANNEL 2UNBALANCED INPUT
H. CHANNEL 1UNBALANCED INPUT
I. AC POWER LINE
J. FUSE HOLDER
K. CHANNEL 2MAIN OUTPUT JACK
L. CHANNEL 1MAIN OUTPUT JACK
R-3

V. Performance Graphs
DS
Idb
Odb
-Idb
2db
mmm FREQutNQ RES!
MM
:
PON!
16 ohm load
8ohm load
4ohm load
,1Hz 1Hz 10Hz 100Hz IKHz lOKHz lOOKHz
Fig.RVWJ Nominal Frequency Response
Fig. RVW.4 Nominal Phase Response
R-4

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Fig. RVW.5 Nominal Crosstalk
Fig. RVW.6 Nominal Noise Spectrum

100Hz IKHz lOKHz lOOKHz
Fig.RVW.7 Nominal Output Impedance
(degrees)
lOKHz lOOKHz
Fig.RVW.8 Nominal Output Phase Angle