03-11-2015, 06:33 PM
You want to use Kapton tape which has a very high insulating factor ( in the thousands of volts...see link for an example. Do not use metalized mylar tape.
https://www.surplussales.com/RF/RFTeflon-Mylar.html
VE6ZRT
https://www.surplussales.com/RF/RFTeflon-Mylar.html
VE6ZRT