Is a Sencore Mighty Mite IV tube tester a decent tester?: Or should I try to get something from the 70’s to the 80’s? The Mighty Mite VII was there last one made. And even Heathkit had one until 1990. I know it is not a conductance tester which is more desirable, but it is in excellent condition. I will use it in testing tubes in old ham radios I plan in refurbishing from the 60’s.