Country of Manufacture:Japan
Speeds: 3 3/4, 7 1/2
Max Reel Size("): 10.5"
Number of heads: 4
Head Composition: Permalloy
Head Configuration: Stereo
# Motors: 3
Frequency Response:7½ ips: 20Hz to 28kHz with LH tape 3¾ ips: 20Hz to 18kHz with LH tape ( 3dB)
Wow and Flutter:less than 0.04% at 7½ ips, less than 0.08% at 3¾ ips
Signal-to-Noise Ratio:better than 60dB at 7½ ips,better than 55dB at 3¾ ips
Sound quality rating:7 / 10
Long-term reliability rating: 8 / 10
The RT-909, an auto reverse / auto repeat-playback stereo tape deck produced from 1979 until 1984 , has four heads (erase, record and two playback).
The similar RT-901 did not feature auto-reverse and thus only had a single head (and a few less controls.)
Both recorders were rack-mountable and designed to take 10½ ” reels. A closed-loop dual capstan drive system isolated the tape at the heads from any external interference, which resulted in a constant tape-to-head
Stereo separation: more than 50dB / Crosstalk: more than 50dB / Distortion: no more than 1% at 7½ ips / Bias frequency: 125kHz / Erase ratio: more than 60dB / Semi-conductors: 4 Fets. 43 ICs. 121 transistors. 125 diodes. 2 photo interrupters / Rewind speed: approx. 120 seconds (10½ reel 720m tape) / Inputs (sensitivity / maximum / impedance): mic x 2: 0.316mV / 80mV / 27K ohms, 6mm phono jacks line x 2: 50mV / 25V / 50K ohms / Outputs (ref.level / max / imp): line x 2: 450mV / 900mV / 2.6K ohms headphones: 50Mv / 100mV / 8 – 250 ohms / Dimensions: 19 x 13½ x 12½ ” (480 x 340 x 318 mm) / Weight: 47lbs (21.5kg / quarter-track stereo