RQ-445 Audio Electronics

The National Panasonic RQ-445 power amplifier has transformer output driving an 8-Ω loudspeaker. Transformer T1 splits the phase, and TR5 and TR6 consisting of 2SB324, amplifies each phase to drive the primary windings of transformer T2 which recombines the phases and drives a loudspeaker. There are six transistors in the tape recorder amplifier section and one for the bias oscillator.

In these early units, the motor did not have any electronics for power regulation, and they simply connected it across the power planes. In this radio cassette, the motor was 6 V DC with mechanical governor.

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