[quote author="uk03878"]I have another idea...
Some of the following boards
BA182C, BA211, BA205 to compliment your BA283s[/quote]
I agree: BA284, B182C, B205, B211.
BA284 is the most interesting IMHO: you can make a 1290 or a 1073 (1063, 1064, 1065, 1066, 1067, 1069, 1070, 1072 too?). Other boards could be breadboards cause they are very simple.
I think we could find cheap alternatives for rotary switches: russian rotary on ebay.
When I?ll get two working BA283 with original traffos (I already have carnhill VTB9045 [10468] and wait for « special L01166 » group order), I?ll try to insert BA284. I?ll post a wiring diagram à la Cayacosta cause I think this project is tough because of wiring between cards and switches, right?