Replacement power cord repair. you can fit a "2.5A Figure of 8 Mains Power Inlet" Maplin part number RY16S to replace the original power socket and use a standard figure 8 power cord. To do this requires a little knowledge and a little soldering.
Step 1. Remove the insides. Undo 6 Phillips, left, middle and right at the top and bottom of the unit. There are no additional connections between the unit and the case.
Step 2. Remove (undo two screws) and de-solder the three wires from the old socket. The centre wire (black) is the earth and this needs to be insulated and coiled up out of the way. The two remaining wired go directly to the power transformer.
Step 3. Get a suitable piece of stiff plastic (old cassette case will do) and cut it to size for the hole left by removing the old power socket. Drill holes to match the two fitting screws.
Step 4. Make a correct hole in the stiff plastic to fit the "2.5A Figure of 8 Mains Power Inlet". Two new fitting nuts and bolts will be needed to hold the new socket in place.
Step 5. Solder the two wires (red and white ones) to the new socket making sure to slide the two transparent insulators over the new solder joints.
Step 6. Re-fit the replacement Figure 8 socket back where the old one was using the original screws. You can now use a standard power cord, but the unit is no longer earthed. This should not be a problem as the entire unit and box is made of plastic.
Note: When this repair was completed and the unit run from 220V AC, there was a significant amount of AC hum. I would also suggest replacing the 220uF 10 volt capacitor in the power supply with "470µF 16V 105°C Radial Electrolytic Capacitor" Maplin Part N90KF for example. This would remove the hum.
NHS, July 2014
