Gallien-Krueger 8000RB, Руководство по обслуживанию

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800RB T/O Procedures
Rev.1- 2/1/88
1) Inspect wiring on PC boards.
2) Connect power:
A) Variac at zero.
B) Speaker on B ,scope on B.
C) Load off.
D) Trimpots halfway.
E) Tones and master on 10, filters out, volume off.
3) Gradually adjust variac to 50 Vrms. Listening to speaker and watching scope signal should pop negative then go
to zero.
4) Check regulated supplies: (+or-) 14.5 V.
5) Adjust variac to 120V and turn speaker off.
6) Set bias:
A) Adjust 38R TP to get 5mV across R48, R49, & R50 (the most pos. of the 3), and R54, R55, &R56 (the most
neg. of the 3).
B) Adjust R14 to get 5mV across R25 & R26.
7) Connect sine input ( 200Hz, 20 mVp-p) – 44dB.
8) 8 ohm load for 100W amp, 4 ohm load for 300W amp.
9) Check for full power on high and low amps.
A) Slowly turn up volume until amp hits the rails- check output on both amps: 100W= 32 Vrms, 300W=
40Vrms.
B) Check master pots when looking at output of both amps.
10) Turn loads off.
11) Connect square wave input ( 200 Hz, 20 mVp-p) –44dB.
A) Boost on zero, volume at 2 o’clock.
B) Test attenuation and filters.
C) Test tone control.
D) Turn on bi- amp- check if crossover works on both high and low amps.
NOTE: When test filters, tones and crossover compare w/ figures.
12)
Turn bi-amp off.
13) Check direct out- NOTE: If direct out does not seem right- use DVM should read .6Vrms at full power (AC)
14) Remove input, speaker on, no load.
15) Noise and tap test:
A) <300mV- all controls on 10, contour off.
B) <500mV- all controls on 10, contour on.
C) <700mV- all controls on 10, contour on, crossover on.
D) <70mV - volume off, controls on 10, contour on.
E) <40mV - volume off, controls on 10, contour off.
F) <6mV - volume off, controls on 10, boost off, contour off.
NOTE: <30mV- volume off, controls on zero, bi- amp highmaster on 10. This is to be done while listening to high end
of the amplifier.