Last week, a good friend purchased a very nice example of a Marantz 2230. I had intended to give this to a local technician, but he is busy with his regular job for the next month or two. So, I believe that I will give this a go. I have a good solder station, desoldering tool, a dual trace oscilloscope on the way, a good Fluke 87 DMM, a bench, lots of hand tools, etc. I just finished downloading the manuals/schematic from the database and will create a binder over the weekend. I work as an industrial electrician, and have worked on PCB electronics, off and on. Recently, I fixed up a Crate tube guitar amplifier - reflowed solder joints, made some tried and true circuit modifications, all with good success. I have also worked on a couple of SS receivers. One, a Sony, is still disassembled from over a year ago - divorce, relocating, etc. I didn't want to get it out until I was sure I was ready to get back into it. Then this Marantz came up. My friend found a pair of EV Interface 3 Sentry II speakers, which I have already fixed up. He intends to drive them with the Marantz. I will document my progress here over the next couple of weeks. Please feel free to comment, constructively of course. I hope to leave a decent thread for others to follow, complete with pictures and in depth discussion of component choices, as well as any problem solving scenarios encountered. Since I have several other receivers that I would like to work on, I have the following questions regarding test gear: How important is a signal generator? Is an app sufficient for this purpose?