Ca Designs MI1A monitor interface

Ca Designs MI1A monitor interface

Used with some small marks

The C.A. Designs monitor interface MI1A is a converter for transforming signals from RGB analogue video with composite sync on green into VGA-type video signals, similar to those from a PC graphics adaptor.  It may be used to enable VGA input video monitors (or printers) to receive their signals down long cable runs, from remote signal sources.  RGB video with suitable timings may be made compatible for LCD monitor display.  It features balanced (75 ohm impedance) inputs and adjustable cable compensation / gain, reducing common-mode interference and picture degradation due to cable losses.  The output is similar to VGA analogue video with synchronisation signals switchable to any of five different modes:


 TTL separate horizontal & vertical syncs - switchable polarities
 switchable retiming of horizontal sync
 combined H & V sync for MAC type monitors
 switchable phase-locked loop oscillator (some LCD monitors are very sync sensitive)  VGA video outputs are constructed from the input signals with sync pulses removed from the green channel.  Sync pulses are removed from the incoming green signal, restored to clean condition and output as TTL-type signals