Hi, The schematics for the Marconi SMR-3 , these you can find them at the following link ; http://bama.sbc.edu/marconi.htm With kind regards, John Bernaerts (dxa86) Antwerp,Belgium Loc: JO21CC RIG: HF: Icom R70/71, Racal 1792/17L, DX-One,Longwire WX:RX2 + crossdipole