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In Reply to: TV-7 tube tester line adjustment problem posted by Richard.Sun on July 3, 2012 at 10:00:19:
Hi all, I borrowed a Fluke 15B digital meter and a Heathkit IT-17 tube tester from my friend, and did some tests.(1) 5Y3 and 83 rectifiers are all tested good, so no problem with the tubes.
(2) The resistors are tested good (R124 = 245k Ω, R123 = 1k Ω, and R125 = 1k Ω), but there is a small blue resistor (= 2k Ω) bringing my attention (please see photo1, red circle), as based on the maintenance document (page10, Figure 6), this 2k Ω resistor should not be in line voltage test circuit (by the way, my tester is TV-7/U, not the later models: TV-7B/U or TV-7D/U).
(3) C103 is being replaced by a VISHAY 100uF / 25V capacitor (please see photo2), and the test reading I got for this VISHAY capacitor is: capacity = 2.5 — 10 nF (far less than 100uF), resistance = 258.4 Ω.
Does this suggest that the problem lies with the filter capacitor (C103)? Also, I am concerning about that small blue 2k Ω resistor in line test circuit — should I remove it?
Many thanks,
Edits: 07/07/12
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Follow Ups
- RE: TV-7 tube tester line adjustment problem - Richard.Sun 00:08:18 07/07/12 (5)
- RE: TV-7 tube tester line adjustment problem - Jim McShane 15:13:38 07/07/12 (2)
- RE: TV-7 tube tester line adjustment problem - Richard.Sun 19:29:10 07/07/12 (0)
- Her prices seem pretty reasonable. . . - John PA 15:40:59 07/07/12 (0)
- Photo 2 - Richard.Sun 00:12:18 07/07/12 (0)
- Photo 1 - Richard.Sun 00:10:48 07/07/12 (0)