B&K Tube Testers

B&K Tube Tester Advertising

Finding advertising for B&K test equipment is pretty easy; finding tube tester advertising is something else. Although pretty common during the late 1950’s, most tube tester advertising was pretty well obsolete nearing the end of the 1960’s. Also, towards the ‘end’ of tube tester advertising, most advertisements ‘shrank’ from a full-page, two-color treat for the eyes, to a postage-stamp size ‘blurb’ at the back of the magazines. Only EMC continued to advertise the same emission tester toward the end of the 1960’s and into the 1970’s. The earliest advertised emission tester from B&K I can find is most likely the Model 600. A sample advertisement can be seen below, and this one was pulled from the July, 1963 issue of Radio-Electronics.

B&K 600 had many features flaunted towards the TV service technician.

What you may notice about the above advertisement is the bravado that this tester is so small, compact, and easy to set up. That is very true, but let’s look at the B&K 600 a little more closely.

  • The claim “Tests TV and Radio tubes – both old and new” isn’t quite true. You cannot test a 45, 47, nor an 83 type tube. I’ll let that tall tale go, as the B&K 600 does have other great features.
  • The B&K 600 checks each section of multi-section tubes separately. That is definitely the preferred way to do things.
  • The gas/grid emission test is sensitive up to 100 Megohms. This is simply a ‘better’ gas test than seen on many other tube testers.

I like the B&K 600; it makes an excellent back up unit, or I can I use it to simply check out a tube for gas and/or grid emission a lot more thoroughly than even the fanciest Hickok. Below is a sample full-page advertisement for the B&K 606, a very similar tester to the popular Model 600, with simply a few extra sockets to test newly developed tubes.

B&K 606 was a popular tube tester with TV service technicians.

What I like about B&K advertising is they usually had very colorful ads. The early examples used a lot of yellow and black (the B&K colors!), while the later ads used a lot of blue, as seen on the testers themselves. The ad above is from the February 1968 issue of Radio-Electronics, and the price seems quite reasonable for the time. B&K making an emission tester almost into the 1970’s symbolizes who they were targeting; the TV technician. The repairman making house calls did not want to take the time to set up his tester for each tube in the television, so the faster emission tester was actually preferred. As long as there were tube televisions, the repairman needed a tube tester. The promise of faster calls with fewer callbacks (because the Model 606 tests tubes ‘under load’) apparently meant more money in the repairman’s pocket.


Next in numerical order is the Model 625, which can be see above. From the color-scheme, you should deduce that the advertisement is actually much older than for the Model 606. Why B&K started numbering their tube testers in a ‘backwards’ numerical order is a mystery to me; they may have simply ran out of ‘forwards’ numerical numbering schemes to use! Worth noting is that the B&K 625 has a multimeter section, much akin to the Hickok Model 605 (one of a few Hickok tube testers that also had a VOM function). I have also seen older Superior tube testers (such as the Model 920) have this VOM ‘extra’. Other than that, the Model 625 is an emission tester, albeit one that tests tube ‘under simulated load conditions’. The meter movement is purportedly sensitive enough to detect grid emission ‘over 100 Megohms’. This would put the Model 625 in direct competition with the Sencore Mighty-Mite line, although the B&K unit can also test television CRT’s.

B&K500 parallels dual-triodes, but is still a very good tester.

While not in numerical order, next up is a sample advertisement from the B&K 500. I seldom use my own example (and I have two of them), because I am not 100% sure I like the idea behind this tester. In order to save time in testing dual triodes tubes (like the 6SN7 or the 12AX7), the tube tester puts the triodes in parallel! There is now just one test position for the entire tube, and I am supposed to be thankful for this time saving design. The owner’s manual mentions that the reading will reflect the fact that the two triodes are in parallel, and a weak section will lower the overall reading. I still like B&K 500 because of the tests is does perform (grid emission, leakage, life expectancy), but wish I could have the option of trying to ‘match’ triodes for a critical application (e.g. phase inverter).

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A pair of B&K conductance tester advertisements.

Next up is a pair of ‘multiple-model’ advertisements, something common in all areas of advertising. The advantage is you learn ‘a little’ about two (or more) models; the drawback is you don’t learn ‘a lot’ about any of the models, just a few common ‘selling features’. Again, not in numerical order, I have advertising from the Model 550. It can be seen, along with the Model 650 in the ad above left. Above right is an advertisement again for the Model 650 along with the Model 675 tester. The Model 650 is a rather large and cumbersome unit, which was replaced with the Model 700, a welcome ‘shrinking’. They got even smaller as time went on, and the more portable units are also much more convenient. Although for me they almost ‘blow it’ with the campy nickname ‘Dyna-Quik’, these are in fact ‘Mutual Conductance’ testers of exceptional quality. As a side note; my own personal B&K 550 and 650 are the only tube testers I have that list settings for reading either strictly ‘Good-Bad’ or ‘True Gm’, also listing ‘Standard Gm’ for each tube. The panel has each socket marked with common tubes for that socket and strictly ‘Good-Bad’ settings. The B&K 650 will also test transistors and diodes, plus has the odd ‘feature’ of having a heater ‘continuity test’ setting. These ads above are both from 1958 issues of Radio-Electronics magazine, and illustrates how expensive these testers were fifty years ago. They also command high resale prices today, because the name B&K is synonymous with quality test equipment. Below are a pair of full-page ads for the Model 675, with a few noteworthy points.

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I don’t know if the Federal Reserve knew B&K were selling money-making machines, but I wish I could find one today!

The B&K Model 675 was never a really popular tube tester, but I do see them once in a great while. You would have to keep tabs on literally hundreds of punch cards, and that’s just the tube portion; the Model 675 will also test transistors! I doubt that any of the transistor punch cards correspond to transistors you would use 50 years after you’ve purchased your tester. However, there are other noteworthy points to consider. If this tester is indeed aimed at assisting the serviceman, how many would appreciate carrying a briefcase full of punch cards as well as the tester? How long would the cards stay in an orderly fashion? To be fair, the advertising claims that only 60 cards will help you test over 500 tube types; you don’t really need a card for the 6L6 and the 50L6. After all, the only differences would be heater voltages. And, in reality, you don’t have any less controls to adjust; there is still the ‘Heater’ and ‘Sensitivity’ settings! You could just as easily save yourself $50 and get the Model 550. But the advertising boys will be advertising boys, and the Model 675 is touted to be faster and easier to use, and will sell more tubes for you. With all of these benefits, why not make the Model 675 exclusively? And, to show that B&K didn’t always use colorful advertising, here is an old Allied Radio catalog insert for the same B&K 675.

A bland ad for a pretty cool tube tester.

Of course, I couldn’t leave it alone, so I’ve taken the liberty to color it ‘a little’ (call me the Ted Turner of old advertising). It still doesn’t look as good as the full page advertising from magazines like Radio-Electronics we see above. Perhaps B&K opted to be frugal with wholesale catalog inserts, thinking only the prospective ‘jobbers’ would view it. However, looking at both ads (and accepting the colored one as ‘stock’), which tester would you prefer? Hopefully you see how important old advertising is, and why I scour them for information.

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B&K 700 advertisements extols the virtues of this “up-to-date tester”.

Surprisingly, there is a lot of ‘alternate’ advertising to be found promoting the B&K 700, but only a select few for the 707, and none that I can find for the 747 tube tester. Above is just one pair of examples for the B&K 700. These advertisements were common only in ‘trade’ magazines such as Electronics Technician and PF Reporter (a publication from the Sam’s Photo Fact people), and other ‘versions’ often used a ‘cut-and-paste’ method of moving arrows and word ‘balloons’ around. Some advertisements used ‘stars’ rather than the arrows as seen above right. Perhaps these later models came at the ‘tail end’ of the tube and tube tester ‘business’, and advertising these dinosaurs soon became an afterthought. Below are the only advertisements I have yet to find for the B&K 707. These are not just ‘samples’; these are the only advertisements I can find, period.

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B&K 707 advertisements mention ‘exclusive B&K patented line voltage compensation’.

The advertisement seen above left (taken from the September, 1965 issue of PF Reporter) mentions a few noteworthy points. Ignoring the bravado that the B&K 707 will test all types of tubes, we get to the ‘feature’ of the ‘exclusive B&K patented line voltage compensation’. It also reminds the technician that the ‘switch section’ (located at the bottom of the panel) tests tubes for emission only, but at ‘current loads to simulate actual operating conditions’. The advertisement seen above right (taken from the November, 1969 issue of Radio-Electronics) is a full four years ‘younger’ than the advertisement seen above left, making me wonder about the R&D work going on at B&K during this time. It really is still a tube tester that is fast, and easy to use. Should you own a B&K 707, do ‘look after it’, and make sure you have the owner’s manual. 

All in all, I really do like B&K tube testers, as well as B&K tube tester advertising. The older ads are pretty interesting in their use of colors that match the tester’s own color scheme, and the sales pitch really tries to impress upon you that B&K tube testers are somehow better than any other tube tester. It seems to have worked, as most older TV repair shops I have visited use more B&K test equipment than any other brand. And I have found more B&K tube testers in these repair shops than all other brands combined (which could explain why I own just about every B&K tube tester every produced).

One thought on “B&K Tube Testers

  • 28 January 2023 at 20:21

    What heppened to the B+K Calibration page?


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