>W6NQ wrote: > >> A gassey tube you can't tell for sure without a hypot tester. > > >The TV-7 series of testers can test for gas and shorts. > It takes c. 3kV to gas-check a 572B. - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, www.vcnet.com/measures. end