68kMLA Classic Interface
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| Click here to select a new forum. | | W?here to meter other voltages Color Classic analogue board post recap | Posted by: captaineos on 2023-01-01 17:37:45
Hi everyone
Grateful to have 68KMLA going strong. Jeremy from Australia
Am doing a comprehensive service of my colour classics, re-capping the power supplies and enjoying it.
I have put together my own cap list, resistor upgrades and taken notes.
One thing I can't work out is where I can safely meter voltages from - specifically high voltage. Not anode cap.
Situation is colour classic recapped -> now turning on -> G2 was too high so nipped the pot back and now have perfect black levels / strong contrast.
However
Vertical bounce / UNSTABLE image (slight!)
Enough to make your eyes sore but slight enough to make you think twice
I explored an idea of mine that maybe a resistor or component is getting too hot but it's there from cold boot / an industrial blower pushing cool air over board and raster the same.
Have put a fair amount of time in reflowing / desoldering / resoldering / cleanup / ensuring some traces patched over for good continuity.
I assume I have an unstable high voltage or low high voltage at some point but can't find any reference to something like "test point 8 should be 200v".
Halp appreciated. From the molex hard drive connector I have verbatim +5.0v and +12.0v present. | | 1 |
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