Logitech Canada 210 wireless keyboard with "multimedia" functions, two rotary encoders.
Feels heavy and sturdy, but also making squeeky noises when twisting base.Over a dozen screws, no latches of any kind.
Connector at top side of the keyboard.
Buttons do not fall out regardless of position.
Left encoder.
Manufactured in 2004.
Two metal plates are used to keep pressure at contacts.
Two crystals: 13.54 MHz and 13.57 MHz.
MC9S08RC16FG - HCS08 Freescale MCU. 16kB FLASH, 1 kB RAM.
Radio part is made of few transistors.
Loop antenna: