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Jackson 561 Tube Tester

This article will discuss repair and calibration of the Jackson 561 tube tester. High voltages are present, repairs should only be attempted by a qualified technician. Copyrighted, all rights reserved. Introduction The Jackson 561 appears to be a rare (uncommon) model. Very little documentation exists, and I have seen only a small number of them

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Jackson 634 Tube Tester

If you appreciate vintage tube test gear, you will enjoy this 1940 vintage Jackson 634 Tube Tester. It is an excellent choice for anyone looking for a quality, well-built, tester that can test the VERY OLD tubes, such as #50, 01A, 1V, #10, 2A3, #15, #19, HY113, HY115, HY125, #26, #45, 71-A, #83, etc. This

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