Well, I've been beating my head against the wall for the past week trying to get these N detector preamps to work with no luck whatsoever. I thought there may have been some issues with the PCB that I had made. Some of the holes were smallish because I designed it to one fab house's specs and then sent it to another, so those holes had to be drilled out. Doug had also mentioned the possibility of parasitic capacitances being a problem and Chris brought up the point of the battery symbol on the schematic being reversed. So eventually, I went back and bread boarded a new circuit to try it that way... still nothing. The next step was to strip everything off of the bread board and try it again, because maybe I made a mistake wiring it...
With all of the parts sitting in a pile on the table I started over, picking up one of the transistors and what do you know?!!! It says 2N4124, which was odd because the circuit only uses a 2N5087 and 2N3904. I picked up the other and it says 2N3904. So I grabbed the little baggie of transistors that I got and the tag says 2N5087, but all of the parts inside say 2N4124 -- not only the wrong part, but it's a NPN instead of a PNP!!!
I guess I got too comfy just reading the labels on the baggie and not actually checking the parts!