Matched Pair Sylvania 6SJ7 6J8P Vacuum Tubes NOS-Testing A Talking Picture This lot of four black

This lot of four black glass Ken-Rad 6D6 tubes was tested on our Jackson 648 Mutual Conductance tester for shorts

US-manufactured Amperex 7699 tube tested to spec on our Paul Hart-calibrated TV7/U

Tube shield dimensions are as follows:

This matched trio of Raytheon 5Z4 rectifier tubes were tested on our Paul Hart-calibrated TV7/U for shorts

A nine out of ten

Matched Pair Sylvania 6SJ7 6J8P Vacuum Tubes NOS-Testing A Talking Picture This lot of four blackThis new old stock testing, perfectly matched pair of Sylvania 6SJ7s was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 58 for Tube One and 60 for Tube Two where minimum (65%) is 40. Both have bj date codes. I am playing them as I write in my Musical Paradise MP 301 MK3 and they sound excellent. They are lightly microphonic and not suitable for environments with