It really sounds like a extremely simple repair, the electrolytics have dried out. The caps can be found from several outlets. I would also like to add something that most here already know, but MR EDD is a awesome base of knowledge, and without him some of us who are just getting started like myself, would be lost. Heres a big thank you for what you do for us. The schematics that you send in your follow up emails are incredible. what program do you use that allows you to copy and do these things? But I still have a GE 408 that I have had to let go of for a few days, but plan to retrace sometime today, and see if I can find the open that I know exists. Your Airline radio probably just needs the electrolytics replaced, and who knows you may hear some awesome am coming thru that speaker.