CRTs are an aging technology and a technology that's even far more gone is CRT projectors. Those things with three CRT projection tubes that need to be lined up to project an image correctly.
Now, here's my question, what do you think would happen if someone tried to use a cathode ray timing gun on a projection CRT system? I know that CRT type guns do work on 'Rear-projection televisions', those flat 'jumbo' TVs that existed before LCD and Plasma took over. Infact most delux Time Crisis and other game cabs seem to be built around 52" RPTVs. So what happens if the electron gun's beam is drawing on a screen hanging off a wall instead?
I'm honestly just curious and have no access to a CRT projector to even test the idea but I think it'd be cool if it did work.