[paul cotter (OP)]

One of my 'scopes that I use routinely has developed a problem and I can't find a circuit diagram online. The focus failed while in use and when I opened it up I noticed a tiny amount of tracking occurring on the sub-assembly carrying the brightness and focus pots. I scraped away the bit of board where the tracking was occurring and the problem was cured. Unfortunately several days later the focus failed again and this time there is nothing obvious and I need a schematic. I could trace out the relevant circuitry but this would be time consuming and other task are building up.