This Knight Series 600 Tube Tester was calibrated on 3-11-18 according to the "Knight "Series 600" Tube Checker" Manual. The calibration was more accurate at 117V House Voltage which is typical with vintage electronics. Only basic electronic skills are needed to follow the Calibration instructions which is the beauty of this tester. The Tester works. I have conducted a test of a 6L6 and a 12AX7 and the tester is operational. The Simpson Meter is in excellent shape. The Case shows some wear, The actual Tester Body is in better shape than most. Please review the PICs which are a part of the Description. The Roll Chart Rolls kind of rough as usual so I use the .pdf documents that are on the Bama site. Using the .pdf documents is much faster than scrolling through the Roll Chart. The Manuals are available for Free On-Line and upon request from the winning bidder I can email you 2 different manuals, one with the Tube Data in it. I can also email you the schematic and parts list. There is a Manual in Dutch but you will get European Tube Data that is easy to understand. These are mostly avaiable from the Bama Site and other online sources if you wish to download them yourself. Sold As-Is.

Here I demonstrate the Test of a 6L6 (5881). The Tester reads as I would expect for a 6L6:

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Here I demonstrate the Test of a 12AX7. The Tester reads as I would expect for a 12AX7:

Knight Series 600 Tube Checker Test of 12AX7 Demo 4665 - YouTube

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Here I show that the Short Light Works:

Knight Series 600 Tube Checker Showing Shorts Light Works 4664 - YouTube

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