The low-frequency amplifier "Lomo 6U-34-3U" was manufactured by the Leningrad Optical-Mechanical Association named after V. I. Lenin since 1975. Application amplifier for working with film equipment that works with 16 and 35 mm film. The frequency range of reproduced sound when watching films on 16 mm film is 60...6000 Hz, on 35 mm film or from other inputs - 60...10000 Hz. Nominal output power 12 W. The required voltage is 60 W. The ULF operates from a silicon photodiode, a magnetic head, a microphone or a signal with an output voltage of 0.8 V.
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