Sony WM-FX493

The WM-FX493 was a Walkman Radio Cassette Player manufactured in 2000 by the Sony Corporation. This model and the WM-FX493ST were available in the US markets. The models for the Canadian market were WM-FX491, WM-FX491ST, and WM-FX493ST. In the UK, the models available were WM-FX491 and WM-FX493. These were all similar looking units with slight differences in their functionality such as the AM band frequency range and remote control option. They all had the same tape transport mechanism MT-WMEX404-147 that Sony had used in the WM-FX477. These units were 3 V systems requiring a pair of AA sized batteries. The Sony LR6 (SG) provided 25-hours tape playback time and up to 40-hours radio reception. It was a small pocket sized unit measuring 115.8 mm × 83.2 mm × 30.1 mm, and mass 195 g with batteries.

Features

• 24 FM presets
• 8 AM presets
• 25-hours play time
• Mega Bass
• AVLS
• Remote Control (RM-WMF5)

Review

In 2000, this was one of the most modern offerings from Sony, and straight away, you can see that used plenty of modern plastics and materials to reduce the carbon footprint, and consequently it was easily recycled. At this point in history, the semiconductor technology they employed was way ahead of its time and as a result, the sound quality is very high even though the case is plastic. The tape transport mechanism was an almost perfect design, which they took from the WM-FX477.

This Walkman uses three main integrated circuits, which were some of the most advanced used in consumer electronics in 2000. The system control computer was the TC9327AF, which took care of all the housekeeping duties such as motor control, LCD display, and switch decoding. The TA2104AFN was the single chip radio solution that had built-in FM/AM front-end, IF amp and FM multiplex. The radio reception, sound quality, and separation were extremely good. One should remember that the headphone cord also doubles as the antenna. Hence, reception quality may vary if you do not have the original headphones.

For the preamplifier equalizer and power amp, they do not disclose the IC name and simply call it the EG Unit. Interestingly, this IC also provides the logic drive for the three coils of the M901 motor. In conjunction with the HP901 audio playback head, this IC produces excellent sound, providing one uses a good pair of headphones.

Changing the Drive Belt

Changing the drive belt first involves opening the unit which is a tricky job for the average hobbyist but doable. Usually, a pair of screws under the cassette lid requires undoing. As well as the plastic claws around the edges, there are claws extending into the cassette compartment, which secure the other half of the outer case; those will need to be disengaged before the cabinet sub assembly comes off. For some of you, it will take seconds, and others, the terms of your natural lives!

Unfortunately, the drive belt is under the main audio board, which requires removal. In order to remove the main board you will need to unsolder four wires from the motor. The engineers have also kindly provided access through the battery compartment for adjusting the tape speed using the WS-48A calibration cassette.

Price/eBay

These are sometimes for sale on eBay and the price can vary depending upon the condition. Although the case is plastic, the electronics was high-end, and the sound quality excellent. A unit in mint condition and good working order together with the original box and headphones can fetch over fifty pounds on a good day. Just the unit requiring new belt would be around ten pounds. The cost of changing the belt can be considerably more do to it being a time-consuming job.

In this multi-page article, you can see photographs of the original headphones and box so you know what to expect when you buy.

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