Tested at 87/86 & 93/82
on a calibrated TV-7D/U tube tester on which 62/62 is the minimum
***On some tubes the minimum being 65% of the typical new score is not a workable formula on the TV7-D/U. So a % score is not meaningful and only an actual meter reading is given. Some of these are:
most rectifiers & diodes - 1U4 - 6BL8 - 6BM8 - 6CW5 - 6DA6/EF89 - 6DE7 - 6DJ8 - 6DR7 - 6EA7 - 6EM5 - 6EM7 - 6GL7- 6GM8 - 6GW8 - 12BH7 - 13DE7 - 13DR7 - 22KV6 - 76 - 80 - 5842
*We use the following testers:
*Dan Nelson calibrated TV-7D/U with sweep tube adapters, & digital meter with plate current test at 150V.
*Paul Hart calibrated/modified Westmore 501 (Triplett 3444)
* B&K 747B calibrated
Test results may differ between various testers for many reasons such as technical design, aging components, etc. So while test results are a good indication of quality there can be some difference between the many differently designed & maintained testers.