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 35 (click to view)
Troubleshooting
6-2 Checkpoints by Error Mode
6-2-1 No Power
Symptom - The LEDs on the front panel do not work when connecting the power cord. - The SMPS relay does not work when connecting the power cord. - The power of the unit seems to be out of order.
The SMPS relay or the LEDs on the front panel do not work when connecting the power cord if the cables are improperly connected or the Main Board or SMPS is out of order. In this case, check the following: - Check the internal cable connection status inside the unit. Major Checklist - Check the fuses of each part. - Check the output voltage of SMPS. - Replace the Main Board.
Troubleshooting Procedures
Are the AC IN socket connector and the Main SMPS CN800 connected? Yes
No
The AC IN socket connector and the Main SMPS CN800 connected
Is the Fuse (F801S) of the Main SMPS Power Input Part blown? Yes
No
Replace Fuse (F801S)
Main SMPS CN804-1 Pin 3 : STB 5V Pin 8 PS-ON : Check to see if it is 0V Yes
