Performance Verification - Marantz SUPERSCOPE BLA-545 Service Data

BLA-545/A-545/BLA-530/A-530
7. PERFORMANCE VERIFICATION
TEST PROCEDURE
A. TEST EQUIPMENT
Refer to Table 1 for required test equipment. 3.
B. PRELIMINARY PROCEDURES
1. Make the test setup shown in Figure 1 with the
instrument controls set in the following positions:
Line Switch OFF
Variable-line switch Variable
Wattmeter Switch ON C.
Variable Autotransformer 0 V (fully CCW)
when compared with the resistance of the load itself.
Appreciable resistance in wiring adds to the total
load, resulting in inaccurate measurements of output
power.
Connect amplifier output to load and connect AC
cord to line power. Connect shorting plugs to the
Phono input jacks of the Model BLA-545/A-545/
BLA-530/A-530.
TOTAL HUM AND NOISE TEST
. With shorting plugs connected to the Phono input
jacks and an 8 ohm resistive load connected across
the speaker system output terminals, connect a dis-
tortion analyzer across the load.
Load 8 ohms (0.5 mfd—OF F)
Audio Generator 1 kHz
Output 5 V range
Gain Minimum
AC VTVM 30 V range
2. Make sure that connections between the resistive
load and the system terminals of the Model BLA-545/
A-545/BLA-530/A-530 have negligible resistance
NOTE:
If the distortion analyzer does not contain a built-in
voltmeter, an AC VTVM may be substituted.
Table 1 Test Equipment Required for Servicing
Distortion Analyzer
Tektronix Model T932
Philips Model 3232
Oscilloscope
Circuit Tester
Manufacturer and Model No.
Audio Oscillator Sound Technology Mode! 1700B
ACVTVM
Use
Distortion measurements
Sinewave and squarewave signal source
voltage measurements (AC)
Waveform analysis and trouble shooting and
ASO alignment
Trouble shooting
DC VTVM ;
Model 313, Triplet Model 801
Fluke Model 8000 ''Digital'' Simpson
Voltage measurements (DC)
AC Wattmeter Simpson Model 1379
Monitors primary power to amplifier
AC Ammeter Commercial Grade (1 ~ 10 A)
Monitors amplifier output under short circuit
condition
l Line Voltmeter Simpson Model 1359
Monitors potential of primary power to
Superior Electronic Co.,
Powerstet Model 116B-10A
Use phono plug with 600 ohm
Variable Autotransformer
Shorting Plu
7 across center pin and shell
Output Load
(8 ohms, +0.5% 100 W)
Commercial Grade
amplifier
a
Adjusts level of primary power to amplifier
Shorts amplifier input to eliminate noise
pickup
Provides 8-ohm load for amplifieroutput —
termination
Output Load
(4 ohms, 0.5% 100 W)
Commercial Grade
Provides 4-ohm load for amplifieroutput
termination
Output Load Capacitor
(0.5 mfd)
Mylar
Optional Item. Fabricate in
AC Power Control Box : '
accordance with Figure 1
Optional Item. Fabricate in
Amplifier Output Load Box
. g accordance with Figure 2
Provides capacitive load for instahj lity checks
Monitors and controls primary porver for
amplifier
Provides various amplifier loads ara can
monitor shorted output