All resistors [ volume,ballans,tembr] cleaned \'\'Electronics cleaner\'\'.The work very good.
Specifications

Power output: 85 watts per channel into 8Ω (stereo)

Frequency response: 20Hz to 20kHz

Total harmonic distortion: 0.025%

Damping factor: 60

Input sensitivity: 2.5mV (MM), 150mV (line)

Signal to noise ratio: 78dB (MM), 100dB (line)

Channel separation: 60dB (MM), 65dB (line)

Output: 150mV (line), 1V (Pre out)

Speaker load impedance: 8Ω (minimum)

Dimensions: 430 x 168 x 389mm

Weight: 17.8kg

Year: 1978

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