Optonica RT-9100   Specyfikacja: Type: 4-head, single compact cassette deck Track System: 4-track, 2-channel stereo Tape Speed: 4.75 cm/s Heads: 1 x record, 1 x playback, 1 x erase, 1 x search Tape Type: type I, FeCr, CrO2, Metal Noise Reduction: B Frequency Response: 30Hz to 20kHz  (Metal tape) Signal to Noise Ratio: 67dB  (dolby B) Wow and Flutter: 0.13% Input: 50mV (line), 0.2mV (mic) Output: 1.0V (line) Semiconductors: 19