The AKAI 1720 model reel to reel tape recorder described in this Manual is quite an old unit - circa late 1960's. As a consequence, the description of the mechanical details - and adjustments thereof - is quite critical. The manual does this quite well. The schematics are also well presented and have detailed PCB overlays. Probably the only negative is that some half-tone detail has been lost from the original manual as it has been scanned in simple B&W.
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Text excerpt from page 46 (click to view)
5-2. Replacing the CPU
1. How to remove the CPU 1 Rotate the lock with a flat-blade screwdriver toward the unlock position shown in the figure. 2 Remove up the CPU. 1
CPU lock position 2
unlock position
CPU socket
2. How to install the CPU 1 Position the mark on the CPU to the mark on the CPU socket and put in all pins to the holes on the CPU socket. 2 Pressing two corners marked with in the figure, rotate the lock with a flat-blade screwdriver toward the lock position. 2
mark CPU unlock position mark 1
lock position
CPU socket
Note: Lock the CPU properly, or operation becomes unstable.
