Here is your chance to get a test equipment package that will allow you to do NPR receiver overload testing similar to the tests run by Adam Farson. This package consists of Marconi low pass, high pass, and band-stop filters. With the provided filters, one can do testing on the 160M, 80M, 60M, 40M, and 30M ham bands. I can provide a full set of details on how to do the testing. For $49, you get either the top filter bank or the lower filter bank.
Also included is a Marconi OA 2090C manual that includes schematics for all the filters.