SMT AIV SCSI
Here's the solder side of the board. As well as the connector to the internal expansion socket inside the Master, we have the red, black and yellow flying wires from the original Acorn SCSI interface. Red and black are for power, 5V and 0V, and yellow is for link 6 to change the computer's reference clock from the onboard crystal to the crystal on the SCSI interface.