This last July I made the trip back to Tulsa to see my folks and I found a bunch of old radio stuff I had and used back in the 1970's. One of which was an old 3 channel Executive model 50A with an all channel receiver via a built in tuner. It was made by International Crystal Mfg in 1962. I think it was still new in the box and unused when I got it. I must have moved the mic jack to the front, but never did finish it because it's still setup for the CB band. I plugged it in and turned it on and it works fine. I searched around and did find the manual for it online. Anyway, I just received it last week because before I left there in July I had boxed a few things up and told my folks to ship them to me when they had the chance. What I might do is order some 10-meter xtals from International Crystal in Oklahoma City because they are still in business. I love using old tube CB's on 10-meters because they have squelch control and you can just leave them on 24/7. What I can do is build a linear for it with a built-in receive preamp and I am open to suggestions. I did find the attached drawing I drew up for it back then and looks like I was probably going to modify the mic input for higher gain and needed to know what the stock circuit looked like. No Internet back in the 70's. It would need an amplified D-104 unless it's modified. I might have to throw in a transistor to drive the circuit a bit before its over.