Mac Plus ozone?

Date: Sun, 13 Apr 2008 09:32:36 -0400 I believe the proper name for the water-based colloidal graphite suspension used to coat CRT surfaces is "aquadag". "Dag" is probably just a shortened form. Aquadag paint for repair should still be available. Some old HOTs (horizontal output transformers/flyback transformer) in CRT HV supplies develop cracks in the potting material with age and sometimes expose the connection of the winding to the HV anode lead. This can cause a corona discharge and the ozone smell. There can also be arcing from the HV lead to the chassis. A lights-out inspection will sometimes yield the telltale purple glow of corona discharge. Often, the discharge can be heard by young ears as a "hissing" sound. Good old red glyptal HV dope is the most commonly prescribed cure for insulation failures. I think GC still sells the stuff. Cheers, Chuck