I am just getting into tube testing and tube amplifiers. I bought an Anko Model 360 tube tester on Ebay, and it appears to be broken. When you set the A,B,and C switches and insert a tube (or don't insert a tube) the unit shows 80 on Gas - 80 on Shorts - and pegs below zero on Test. Do I have a filament tester here, or a real tube tester? Not sure where to start on the repair. Any ideas would be greatly appreciated.



