[autoradiotech]

I agree with Doug Houston, the sets that used a 6A7 sometimes had a problem known as a critical oscillator. Try other tubes as Doug suggested, Sylvania seemed to be a better brand of tube here. As Doug also pointed out, there can be corrosion in the ground connection at the tube sockets so I also suggest running a ground wire directly to the chassis from the pins that are supposed to be grounded. Also there was no model CT-3, the first letter of the model number indicates the car(line) that the radio was designed for, the model T-3 was made for Pierce-Arrow MT-3, Reo RT-3, and Studebaker ST-3. I have never seen the osc coil go bad in any 34 or 35 Philco car radio, the 36 thru 38 radios are a different story, check with an ohmeter for continuity to make sure.