I have a complete high gain RGR and one missing a board. If you haven't found a schematic yet, take of picture of the board, some are matching left and right, and I could look at the one's I have. After RGR died, I had friends ask the family if anything was available, but there were no schematicsPlease send me the schematics for the RGR 4 pre as I have a burnt resistor and dont know what value it is. meyerrat@yahoo.com
at his house.