Resolving Keyboard Issues on the Sony ICF-SW7600GR

The Sony ICF-SW7600GR, a well-known portable shortwave receiver, has built a solid reputation for its performance and reliability. I purchased this receiver 20 years ago, and it is likely the last portable shortwave receiver manufactured by Sony. I primarily use it for shortwave listening, and it has functioned continuously for two decades. However, like all electronic devices, it is subject to component degradation over time. This post outlines the diagnostic and restorative procedures I undertook to address a complete failure of the keypad on this radio.

Restored ICF-SW7600GR radio.

Initially, the radio exhibited a gradual decline in keypad functionality, which eventually led to a complete lack of response. I observed intermittent key input before all keypad operations ceased entirely. This symptom suggested a possible discontinuity or short circuit within the keypad interface circuitry.

To investigate further, I disassembled the unit to inspect the internal components. My primary focus was the flexible flat cable (FFC) connecting the front control panel to the main circuit board. A visual inspection revealed significant damage to the FFC. Specifically, the protective dielectric film had delaminated from the conductive traces, leading to potential short circuits between adjacent conductors. The FFC in question is an 18-pin cable with a forward direction, a 1.25mm pitch, and a length of 37mm.

Damaged FFC.

Finding a replacement FFC with these specifications was challenging, both in local markets and popular online electronic component stores. Eventually, I consulted with a manufacturer called Shenzhen Yiwei Technology and was able to obtain a nearly identical cable. The only difference was that the new cable is 100mm long. Since this cable is located closer to the speaker, I carefully bent it and positioned it underneath the speaker magnet. Now, this cable is also available for purchase directly from the AliExpress store of the above mentioned manufacturer.

New FFC arrangement.

After replacing the FFC, I reassembled the unit and conducted tests. I was pleased to find that the keypad had fully restored functionality, with all keys responding as designed.

Replacement cable.

Compared to modern electronic repairs, this repair was quite straightforward. Thanks to its modular design, I was able to complete the repair using just a few Phillips screwdrivers and tweezers.

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