VT 8x4 Video Switcher
This is often referred to as VT 'P169' since in September 2009 it replaced the old VT P169 which was an actual P169. This is actually a lower-quality 8x4 video matrix switcher, as such it shall be referred to as 'VT 8x4' in the rest of this page. It requires a reference signal to switch which input is sent to each of the four outputs. Michael Cullen did an experiment at the end of 2009 in which he took a signal of Clock's Distribution Amplifier board and fed this amplified 'Clock' video signal into the reference of VT 8x4. This allowed VT 8x4 to switch inputs. The DA boards amplify to -0.6V to 2.0V (rather than -0.3V to 1.0V) and video signals aren't the same as black and burst, and there was no immediate advantage in using the video signal from the DA board. Therefore VT 8x4 was rerferenced instead from one of the four 'Black & Burst' outputs of Magic DaVE.
VT 8x4 reliably serves its purpose, which is a combinoation of the original uses of VT P169 and Preview P169 combined.