Analogue monitor board repair

"Hence the question - am I wasting my time without a schematic for this analogue board?" Might be helpful if you mentioned exactly what is or isn't wrong with the unit.. describe the symptom(s), etc.

On Mon, Oct 31, 2016 at 1:44 PM, Adrian Graham <witchy at binarydinosaurs.co.uk > Folks, > > I think I know the answer to this before I even ask, and that answer will > be > 'got a schematic' to which the answer's 'no and I doubt one exists any > more' > but... > > My recent Executel addition has a 5" screen with associated analogue board > that seems to be powered from a display chip I can't find any info on, and > at least one of the adjustment potentiometers has suffered metal fatigue > and > broken: > > http://www.binarydinosaurs.co.uk/STCExecutelScreenPot.jpg > http://www.binarydinosaurs.co.uk/STCExecutelAnalogueBoard.jpg > http://www.binarydinosaurs.co.uk/STCExecutelDisplayChip.jpg > > I've replaced it with a seemingly common 10K modern part that I had in my > spares box but it's unknown whether the display worked at all prior to it > being put in very damp storage, also the rating of the failed pot isn't > known but the capacitor next to it is 50V. > > I've also removed, checked and replaced out of spec capacitors, one of them > was a 680nF 50V radial. I could only find a 63V PET version on cpc's > website > and did much reading on differing capacitor types, concluding that it > SHOULD > be OK. > > Power supply is known good because it's one of my working ones, the > original > is still dead. > > Hence the question - am I wasting my time without a schematic for this > analogue board? > > Cheers! > > -- > Adrian/Witchy > Binary Dinosaurs creator/curator > Www.binarydinosaurs.co.uk - the UK's biggest private home computer > collection? > > >