24 Oct
2008
24 Oct
'08
2:17 a.m.
On Thu, 23 Oct 2008, Tony Duell wrote:
I just want to mention that there were polar-coordinate tubes. They may be
either completely electrostatic or mixed static/magnetic. I've just read
an interesting discussion on the 3DP1 on the net.
Well...one
without deflection plates is rather difficult to use as a
vector display, but that's a matter of complicated and unconventional
One without _any_ deflection system is hard to use as either a vector or
raster display :-) I have several vector displays here. The ones that
were designed by
companies known for making CRT-based instruments like 'scopes -- HP and
Tektronix -- use large-screen electrostatic CRTs. But the DEC VR14 and
the Vectrex video game both use electromagnet CRTs.
The DEC VR14/VR17 are electromagnetic CRTs. The two push-pull power
amplifiers for both ordinates as well as the current through the
deflection coils are quite impressive.
Christian