Re: Corona advice - no not that one!

Michael W. Lynch

Regarding the use of "Black RTV", Certain RTV's are excellent insulators. Keep in mind that TEK used silicone potted HV transformers in the later Type 576.

Here is one recommended product: Dow Corning RTV 732 BLACK This product has excellent Electrical properties. Full Datasheet is available online here:

Here are some relevant electrical details.

"Electrical properties, cured 7 days in air at 25°C (77°F) and 50% relative humidity.

Dielectric strength: 21.6kV/mm per ASTM D149
Dielectric constant at 100Hz/100kHz: 2.80112 per ASTM D150
Dissipation factor at 100Hz/100kHz: 0.0015 per ASTM D150 "

There are likely more materials available that will do the job.

Michael Lynch
Dardanelle, AR

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