RCA 6146 Tube

EB5AGV's TV-7 Tube Tester page

Keep them glowing!

TV-7D/U Repair

This is a page devoted to the TV-7( )/U family of tube testers. These testers have become very popular for people interested in vacuum tube technology. These are portable units, which a size small enought to carry them easily.

As John Shriver commented in the BA list: 'There are 5 variants, TV-7/U, TV-7A/U, TV-7B/U, TV-7C/U, and TV-7D/U. The only operational difference is that the TV-7D/U adds an additional transconductance range F, for very high transconductance tubes. However, there are alternate test procedures for the other testers, but probably with less precision. Only matters on really high-mu tubes. The important circuit difference is that later models have more ferrite beads on the wires to the tube sockets. Less likely to oscillate when testing high-mu low-cap tubes like 6DJ8 or 417A. Otherwise, the differences are improvements in the calibration process and maintainability. For instance, a TV-7/U has some 'Select at calibration' resistors, particularly in the line voltage circuit. Later ones have three sliders on one of the wirewound resistors instead of two. Perhaps these allow you to calibrate around aging of the rectifier tubes, rather than replace them.'

Most of them were manufactured in USA by Hickock, although there are other alternate manufacturers, as Stark in Canada. I own a Stark TV-7C/U, S/N 340, which is in fact a TV-7/U internally (circuit) and a TV-7B/U externally (panel and cabinet).

Technical Manuals and Tube Data for the TV-7 series

Currently I have in my library all of these manuals and supplements. Please, let me know if you have any of the missing ones or if you need any of them. I have put some of the TV-7 Supplement Data online (the ones marked as AVAILABLE below) and plan to add more of them soon.

Resources (TV-7 and TV related)

TV-7 page INDEX

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