Testing 6H30 tubes

Call Upscale Audio in L.A. or Balanced Audio Technology.

While they are both novals, 9 pins, these tubes are not equivalents. Good luck.

Thanks for your input. My understanding is that I could hurt the tubes by using the wrong tester settings, so will look for someone with a 6H30 tester

You could try to find someone with an Amplitrex AT-1000 tube tester or also a Maximatcher preamp tester. They have settings for the 6H30s and test at actual equipment voltages. Some other testers may work if you can adjust the plate and grid voltages.

There are 2 readings, one for mu ( gain) and one for Gm (transconductance). Since this is a dual triode, there are 2 sets of these readings.

The tech should have some knowledge of the 6H30 tube (easy) and ideally, but not essential, the circuit it’s used in (more difficult). Any tube sellers would be able to help you, but would likely charge a nominal fee.

Thanks BarrySandy, will track down these leads