Sanyo M4440 Inside

The Sanyo M4440 has an extremely high quality design and construction. The printed circuit board (PCB) etching and design is to a high standard. They are using conventional components on the other side. The tape drive mechanism mounts on the metal chassis, as does the PCB. There is a conventional Japanese made d.c. motor that operates well even today, and the overall construction is neat. This type of construction is rare today because of the drive towards lowering the carbon footprint.

As you can see, the PCB is very similar in build to the M3330. It has very sharp and clean look, and there are no dry solder joints. There is a small window hatch for cleaning the rubber surface of the cogwheel responsible for the auto shut-off mechanism. One of the first things to fail on this unit is its auto shut-off mechanism. This was due to the fine tolerance of contact with the driving cog, which stopped making contact after the slightest wear to it.

To remove the chassis together with the PCB, the battery wires require desoldering first because the battery terminals remain fixed with the plastic case. These wires also connect to the terminals of the power socket. There are three pillar screws fixing the metal chassis to the plastic case that will also require removal, and then the whole chassis comes out.

To replace the drive belt, one has to desolder some of the battery and motor wires, so that the PCB may lift up from one side.

PCB Soldering

This photograph shows where the two power amplifier chips solder.

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