7 – RCA, GE Balanced 6SN7GTA&B Tubes. I then use the Hickok 539B to confirm the test results and provide an. Hickok’s 539B Specifications state that any tube over. All tubes have been tested and matched on two Hickok Professional Tube Testers.
7 – RCA, GE Balanced 6SN7GTA&B Tubes. I then use the Hickok 539B to confirm the test results and provide an. Hickok’s 539B Specifications state that any tube over. All tubes have been tested and matched on two Hickok Professional Tube Testers.