While returning to Adelaide from Moomba, the crew of a Dash 8 detected smoke coming from around the weather radar. They immediately turned off the equipment, donned oxygen masks and made a PAN call requesting RFF services to be placed on standby. To dissipate the smoke, the crew requested a descent to 10,000 feet where the aircraft was depressurised and the forward outflow valve was opened. After ensuring that there was no smoke or flame coming from the radar unit, the crew made the decision to continue to their destination and briefed the passengers accordingly. Upon arrival in Adelaide the aircraft made a normal approach and an uneventful landing. The flight attendants were later sent for medical attention due to the effects of smoke inhalation. Maintenance investigation by the operator traced the fault to the radar indicator unit. This was replaced and the aircraft returned to service.