I found this info about the 1084: A loud whistling noise indicates a bad flyback transformer (also known as an LOPT). Some 1084 monitors also have digital RGB (PC clone CGA) inputs, and there was such a profusion of minor or major variations that any 1084 might have any combination of analog RGB, digital RGB, and composite inputs.
Dunno if it helps much since the ppl above also mentioned the flyback transformer...
