How do the front knobs on a Zenith 6-D-311 come off so that I can pull the chassis out to check everything out and clear it. Thank you for taking time to read this e-mail. Bill

Bill, the first knob(on/off/volume) is friction fit and should pull off ..The second flat rounded one (dial tuner) has set screw(s). The plastic on these may be warped from time and brittle so be careful..just take your time in removing them.. I have this set(s) in browm, black, and the hard to find white painted version.