https://www.hifiengine.com/manual_library/akai/gx-77.shtml
Akai GX-77
Stereo Reel to Reel Tape Recorder (1981-83)
Specifications
Track system: auto reverse, 4-track, 2-channel, stereo system
Heads: 2 x GX record, 2 x GX playback, 2 x erase
Motor: 2 x reel drive, 1 x capstan
Reel size: up to 7 inch reel
Tape speeds: 3 3⁄4 7 1⁄2 ips
Wow and flutter: 0.03% (7 1⁄2 ips)
Frequency response: 25Hz to 33kHz (7 1⁄2 ips)
Signal to Noise Ratio: 63dB
Total harmonic distortion: 0.5%
Input: 70mV (line), 2mV (DIN)
Output: 0.775V (line), 0.3V (DIN)
Dimensions: 440 x 244 x 227mm
Weight: 17kg
Accessories: connection cords, empty reel
Downloads
– instruction/owners manual 
– dennismiller55
service manual (alt scan) 
– AllanK
–
