olson: Error in Schematic diagram of Olson KB-141
If working on the 4 tube version of this signal generator / tracer, please note that terminals 6 and 7 in the schematic diagram are shown crossed over for the 5687 pre-amplifier tube. Pin 6 should the cathode and 7 is the grid. The tube pin voltage chart also incorrect. The same circuits are used for the Accurate Instruments Model 153 and the schematic diagram for that is correct.