[Hallicrafters] SR-400 and SR-2000 schematics and prototype info

[Jim Liles]

I am having a devil of a time finding schematics and info regarding the SR-400 run 2 thru 5.  The schematics would have part numbers 1S5-000459B, C, D, and E.  Need some help on this one.  Also looking for the prototype schematic and face plate for the SR-2000 that added the CW and Notch filters that were requested by Al Kahn of Electro-Voice.  Thanks for any leads --- Kindest regards Jim K9AXN