Bauer T502 Automatic Duoplay

Marketed in 1978
Super 8 mm film
Lens: Schneider-Kreuznach Xenovar f: 1.2 F: 15.5-28 mm
Lamp: 150 W, 15 V, EFR
Reel capacity: 240 m
Projection: forward and reverse
Projection speed: 18, 24 fps
Film counter: 4 digits, mechanical
Film loading: automatic threading
Sound: magnetic playback on both sound tracks
Soundmode: mono, duo
Track selection: 1, 2, 1+2
Track transfer: 1 to 2, 2 to 1
Frequency response: 50-10,000 Hz for 18 fps, 50-12,000 Hz for 24 fps
Amplifier output: music power 20 W
Sound control: volume, tone, balance
Recording: magnetic recording on both sound tracks
Sound-on-sound: and sound fading
Recording level control: auto and manual
VU meter: recording can be monitored with VU meter
Sound mixing: available
Input terminal: Microphone, Phono, Line-in
Input jack: Phono, Line: 5-pin DIN plug (European type); Mic: 7-pin DIN
Output terminal: External Speaker, Line-out
Output jacks: Ext Sp: 2-pin DIN plug; Line-out: 5-pin DIN plug (European type)
Built-in speaker: 12 W
Synchronized sound socket: double-system, synchronized sound with a tape recorder
Motor: DC magnetic motor
Power source: 100-120-150-200-220-240 V AC, 50/60 Hz
Weight: 10,500 g
Dimensions: 235 (W) x 287 (H) x 365 (L) mm
Made in Germany by Robert Bosch

Projector with Duo Play System, which allowed the voice to be put on the first track and background music on the other.

For instructions on replacing the belts see here.

For instructions on replacing the frame adjustment knob see the video below: