Converting The Mtv1 Into A Mon1 Monitor - Sinclair Microvision MTV1 Service Manual

Converting the MTV1 into a MON1 monitor

Given that key parts of the sets are Unobtanium (particularly the Sinclair-designed ICs on the tuner
panel and, perhaps less so, the Sinclair deflection IC), there is naturally a dwindling number of
scrap sets available for cannibalisation. However, if the basic chassis works then it is possible to
repurpose the receiver as a composite monitor (after the style of the MON1, the composite video
monitor version of the set) by omitting the tuner, video IF and sound panels.
The earlier version of this manual included an incomplete diagram of the MON1 video interface
circuit, which is included at the end of this document. Below is a best-guess re-interpretation of the
circuit; the numbers in circles refer to the same numbers on the coloured main circuit diagram.
It must be stressed that this is a best-guess and some experimentation may be required to obtain a
stable image.
The original MON1 had a BNC socket on the rear panel for video input and a switch to select 75Ω
termination. It would be possible to re-purpose the earphone jack as a video input connection and,
optionally, one of the front panel switches as a termination switch.
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Sinclair MTV1 service manual V2.1