B&K 600-606 tube tester

This article discusses repair and calibration of the B&K 600 / 606  tube testers.  Both models can share the same tube setup data book, and therefore both models are functionally equivalent.    Model 606 will be example shown in this article.  Electrical voltages are present, repairs should only be attempted by a qualified technician. Copyrighted 2010 TubeSound, all rights reserved.

Cosmetically, these models look like a little brother to their larger siblings — B&K 700 and B&K 707. Model 600 shares the same color scheme with Model 700, and model 606 shares the same color scheme as model 707. The wood case construction is similar also.

Electrically, models 600 and 606 are very similar (though not identical) to the “Switch” section (bottom panel) of the 700 / 707, employing the same grid leakage test and very similar tests for Emission Quality and Shorts.

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B&K 607 – 667 Tube Tester

BK 607 tube tester

BK 607 tube tester

B&K 607 case

B&K 607 case

This article discusses the solid-state B&K 607 / 667  tube testers.  Both models use the same tube setup data book, and therefore both models are functionally equivalent.    Model 607 will be example shown in this article.  Electrical voltages are present, repairs should only be attempted by a qualified technician. Copyrighted, all rights reserved.

This series was B&K’s clone of the Sencore Mighty Mite TC162.  While the circuits are not 100% identical, they are close enough to be considered functionally identical.  The B&K 607 weighs slightly less than 6-lbs (without setup book or manual), and size dimensions are: 34 cm L x 24.5 cm W x 11 cm D.  The case folds open and easily accommodates a full size 8.5 x 11 inch setup chart and service manual as shown in the photo above.

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Solid state replacement for #83 tube

I am frequently asked by B&K and Hickok owners to explain how to replace a #83 tube with a solid state version. This question is popular because #83 tubes are scare and expensive. Other benefits are increased reliability (no tube to wear down), less heat generated inside the tester case, and less load on the power transformer. So, if you want to Do-It-Yourself, I will explain how these replacements are made.

I will preface this tutorial with a few caveats: First, this procedure is easier to implement with B&K testers than Hickok testers. Hickok factored in the load that the real #83 tube has on the power transformer, and sometimes you cannot properly set the line without circuit modification. Keep this in mind if you plan to try it with your Hickok — you may be getting in over your head. Hence, substitution may be more effort than it is worth, especially when some Hickok buyers do not want the modification and would have to undo the circuit mods that were made. This leads to the second caveat: not everyone feels that the solid-state substitution works ‘excellent’ in Hickok’s. In fact, some “purists” will not even use a Hickok with a solid-state #83 replacement. They cite the fact that silicon diodes have less voltage drop than a tube rectifier, and feel that the tube test results will not be “pure.”

Personally, I always use a solid-state replacement for B&K testers. For most Hickok, I prefer to use a real #83 tube only because circuit modifications are sometimes necessary, which makes going back to a real #83 difficult for the tube tester owner or future buyer.  This problem is particularly true for the “red-case” Hickok’s.

That said, I have no disapproval with using a solid-state #83 in a Hickok model that lends itself to working well, and have found that any tube “test score” differences are trivial. In my opinion, the people who argue about small test score variations are really over-thinking the purpose of testing a tube — the end-result is NOT a test score, but to ascertain whether the tube will work satisfactory in your circuit. Common sense and practicality are important.

Here it goes…

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B&K 700 & 707 tube tester

©2008, Bob Putnak.  All rights reserved.  This article discusses the B&K 707 Dyna-Jet Dynamic Mutual Conductance tube tester, including repair and calibration. The discussion is also relevant to the B&K 700 (the 700 is almost identical except for socket configuration) and some of the information is applicable to the B&K 650.

To jump immediately to the section that explains the Upgrades and Mods that I find useful, click HERE.

BK 700

BK 700

my BK 707 with custom TubeSound plate current meter upgrade

The B&K 707 tube tester dates from the late 1960s into the 1970s. My manual is stamped August 1969, and a modern tube data setup chart dates 1978.

First of all, a brief explanation of the circuitry of this tester is necessary. Is this a Mutual Conductance tube tester? Well, yes and no.

Tubes that test in the “Jet-Check” section test for mutual conductance, with the exception of diodes/rectifiers (which always test only for Emission). The Jet-Check section is the upper panel (sockets 1 – 35). Tubes that test in the “Switch” section — the bottom panel (sockets 36 – 45), are tested for Emission.

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