> On 24 Nov 2017, at 08:41, Brent Hilpert via cctalk <cctalk@classiccmp.org> > wrote: > > On 2017-Nov-23, at 5:07 PM, Adrian Graham via cctalk wrote: >>> On 23 Nov 2017, at 21:18, Brent Hilpert via cctalk <cctalk@classiccmp.org> >>> wrote: >>> ... >>> You might check the contrast control. >>> I can't find the actual schematic for the contrast control connections, but >>> I 'm guessing the ends are connected across 12V (video board pins 5 & >>> 1/4/10) and the wiper to video board pin 8. >>> The contrast control can be expected to take pin 8 somewhere + to get >>> pixels fully on. >> >> You’re right with pin 8, tracing the circuit I can see why someone >> recommended I check Q101 and Q102 which look OK in my tester. >> The contrast control itself tests OK resistance wise, it goes from pretty >> much 0ohms to 610M. > > 610M ? > I hope that M is a typo. >
Morning! It is, 610k or 0.6M :) Cheers A
