> MSDC Klystrons ran around ten feet @ 32KV applied. If they use Teflon tubing a foot might be sufficient. Different brands are cooled differently so it may depend on the arrangement. -- Ron KA4INM - Of what you see in books, believe 75%. Of newspapers, believe 50%. And of TV news, believe 25% -- make that 5% if the anchorman wears a blazer.