https://www.airforums.com/forums/f449/wiring-new-converter-from-12-volt-panel-101990.htmlSays what the 1985 converter is/was. In a video that came up (googling) it showed the converter in an older Airstream. That converter looked a lot like the OEM one that was in our 1981 truck camper. It was a real beast, made in Winnipeg to a British design--forget the brand name for it.
It did supply 12v when plugged into 120v. It had a battery charger section too. It made loud clunks when it switched. It was very big and heavy. Got rid of that and used a modern converter instead.
bestconverter has an article about Airstream converters. Also something on how to keep the OEM power- on indicator light working if you do swap out the old converter.
An old thread about it--it's a Magnetek 730-2
https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/13748154/print/true.cfm 
