Single Gun Color CRT

[old_tv_nut]

Originally Posted by jpdylon

single gun that early? wow. So is that the "apple" design?

That would be something that the ETF would own or want to own methinks.

NOT the Apple design.

This was a shadow mask tube that had what I would describe as dynamic modulation of the purity settings, so a single beam was moved sequentially to the correct position for red, green, and blue. It was probably MORE touchy for adjustment than a 3-gun tube. For "dot-sequential" color (the RCA system), the beam angle of arrival would be centered on the three RGB phosphors for monochrome, and decentered in the direction and amount indicated by the phase and amplitude of the color difference. This sounds like a real mess, since getting the correct brightness and ratio of RGB simultaneously would depend on whether the phosphor dots continuously covered the screen. If they had any non-emitting space between them, the brightness would drop as soon as you moved the beam arrival angle off-center.