IAN CANADA 70M COMBOMASTER Reclocker Module

The Ian Canada 70M ComboMaster is an expansion board dedicated to the Combo768 USB interface, used in slave mode. It galvanically isolates the USB data and the ground from the source, then reclocks the I2S/DSD signals from external local oscillators. This architecture allows the Combo768 to rely on a clock reference distinct from its integrated oscillators, with the goal of improving timing accuracy and reducing jitter.

Ian Canada 70M ComboMaster: External clocks and audio formats

Two interchangeable sockets accommodate the XO1 and XO2 clocks, at 45.1584MHz and 49.1520MHz respectively, in order to upgrade the interface's clock reference. Reclocking supports PCM streams up to 384kHz and DSD up to DSD512, while high-speed galvanic isolation applies to the I2S/DSD signals.

Ian Canada 70M ComboMaster: Power supply and connections

An isolated 3.3V input powers the clean side of the board, where a local filtering network helps limit disturbances coming from the USB power supply. The I2S/DSD/MCLK outputs use U.FL connectors intended for coaxial cables, while an external MCLK input and a clock selection output are also available as options.

The DIP output connector and the board dimensions are compatible with the Combo768, allowing an upgrade by direct connection. This integration targets users wishing to add isolation and reclocking to their USB interface without modifying the overall system architecture.