From ampwares.com:
Model/Circuit Number:
Years of Production: 1977 – 1980 Era: Configuration: Combo Controls: Black Forward facing with white labels Knobs: Black skirted w/ chrome center, numbered 1 – 10 (EQ knobs numberd -5 to +5) Faceplate
Front: Power Sw, Standby Sw, Pilot Lamp – In, In, Vol, Treb, Mid, Bass, Presence – 1850 Hz, 1000 Hz, 390 Hz, 180 Hz, 80 Hz – Output