Gallien_krueger_800rb_sm1 电路图 维修原理图.pdf
? ? 收音机爱好者资料库 Ra d i o Fa n s .CN ? ? ? ?!?# $?!?%$? treble to 0- Fig.3. B) Hi-mid to 10-Fig.4; hi-mid to 0-Fig.5. C) Lo-mid to 10-Fig.6; lo-mid to 0-Fig.7. D) Bass to 10-Fig.8 bass to 0-Fig.9. 6)Engage Low-cut switch, compare to Fig. 10. (Disengage). 7)Engage Contour switch, compare to Fig. 11. (Disengage). 8)Engage Hi-boost switch, compare to Fig. 12. (Disengage). 9)Engage Bi-amp switch. Compare 100W output to Fig. 13. 10)Compare 300W output to Fig. 14. 11)Set Freq. Knob 10, compare 100W output to Fig. 15. 12)Compare 300W output to Fig. 16. Disengage Bi-amp switch. Noise Test 1)Remove oscillator input. 2)Turn front panel knobs to 10, switches out. 3)Connect speaker to 100W output and listen for noise. It should be smooth and not crackling. Repeat for 300W output. 4)Change AC voltmeter range to 1V 5)Noise( both amplifier outputs) should measure less than 400mV. 6)Engage low-cut, contour, and hi-boost. Noise<400mVrms. 7)Volume to 0. Noise< 110mVrms. 8)Boost to 0. Noise<15mVrms. 9)Engage bi-amp switch. 100W noise< 20mVrms, 300W noise< 5mVrms. RETURN KNOBS TO ZERO, SWITCHES OUT- READY FOR BURN-IN. 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 oclock. 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.
