On Sun, May 8, 2016 at 9:57 AM, Pete Lancashire <pete at petelancashire.com> wrote:
I thought the Tektronix DAS used a custom tri-color
crt, where the
blue phosphor was replaced with yellow.
It is custom, and it is tri-color (red, green, yellow), but it's a
beam penetration CRT that is not a modified version of any normal
color CRT. There is no shadow mask, and it can only draw one color per
field, like the 1951 CBS field-sequential color television, though
that was done with a color wheel while this is done by modulating the
anode voltage (and possibly the deflection drive as well).