The W61CA mainboard appeared when we removed the keypad circuitry and the metal shield under it.

Looking at the mainboard structure, we noticed that it was quite similar to the one in another model examined by the Nikkei Electronics Teardown Squad in the past, namely, KDDI Corp's W53H manufactured by Hitachi Ltd. This is probably because both Casio Co Ltd and Hitachi delegated the development of mobile phones to Casio Hitachi Mobile Communications Co Ltd.

Like the W53H, the W61CA used a mobile phone chipset manufactured by Qualcomm Inc. The 1seg tuner module, which was likely made by Murata Manufacturing Co Ltd, had letters printed on its surface, and those letters were the same as those printed on the module in the W53H. The module had a built-in tuner IC believed to be made by MaxLinear Inc.