Will a 21fjp22 work in place of a 21cyp4

[julianburke]

This is a 100% retrofit and will work perfectly. The gun mounts are the same gun on both tubes and from the 21CY you don't use the 56K resistor with spring that bridges the two anode buttons. I don't know about changing any resistors as you will get better tracking with the 21FB/FJ and will make wonderful color. I did this many, many times in the '60-70's and never any problems. Don't worry about any resistors as nothing has to be changed except leaving off the double button anode resistor for the newer tube. Julian