television (PAL) The
video signal format used in the UK
[where else?].
which (together with the use of a delay line) allows the
receiver to cancel any phase errors introduced in the path
between the studio and the end-user's receiver. Such phase
errors are quite common and would cause the displayed colours
The US equivalent,
NTSC, does not have this feature and thus
requires a user control to correct for transmission phase
errors, hence the mis-expansion "Never Twice the Same Colour".
(2001-06-08)