Which tube tester to keep? 539A or TV-7D/U

Which tube tester should I keep and restore??

  • TV-7d/U

    Votes: 11 68.8%
  • Hickok 539A

    Votes: 4 25.0%
  • Hickok 600A, it's good enough and sell both the others

    Votes: 1 6.3%

  • Total voters
    16

Andyman

Scroungus Stereophilus
Subscriber
So I picked up a TV-7D/U last week a hamfest and now have to determine which tester to keep. The TV-7 seems to work and may only need a calibration, and the 539A hasn't been tested, but comes with issues. I already have a Knight 600 which really does do a nice job for a simple emissions tester, and a Hickok 600A, but want to upgrade the Hickok 600A to one of the others and sell it and the other "big gun".

I want the "name" tester basically so I can sell off these buckets of tubes I have here with an authoritative test behind them and both the 539A and TV-7D have that. I like the smaller size of the TV-7, but it gives test results based on minimum acceptable reading, and the 539A I believe gives average of new, so one reads the lower limit, the other the higher. I have contacted Dan Nelson about the TV-7, and have his price schedule, so I know what that would cost.

What are your experiences out there with these testers and which would you prefer if you had the choice? I've already have two sets of inputs, but they are split, so it's time to poll here to see which one to repair, calibrate and keep.

Thanks in advance!!
 
I have a Hik 533 and 600. like the 600 due to small size.
glad I dont have to decide which one to sell.
Keepin em both and the sencore mitymite tc 162 too.
but wish I had a TV7
 
Regardless of which tester you use for selling tubes,buyers will always crap on your machine:

If you use a Hickok 600A,they'll say it's not as good as a 539.If you use a 539,they'll say it's not as good as a TV-7. If you use a TV-7,they'll say it's not as good as an Amplitrex.If you use an Amplitrex,they'll say it's not as good as a Tektronix Curve tracer. You can't win,so don't waste your time trying to play that game.

The three units you have listed are all ''name'' machines,and if properly calibrated (and that will just be another argument!) should all carry the same weight.
And as none of them can provide the necessary voltages or currents to adequately test power tubes,there's another argument you can't win.

My own testers include the Hickok 600A & 539A,Marconi MU-101(a license-built Canadian military Hickok) and a Jackson 648S.
 
Actually, I've been selling tubes for years using first the Knight and then the Hickok 600A, but just recently came into the other two, so I'm pretty familiar with how it goes. For my purposes, I don't need, 4 and only want to keep 2, one being the lowly Knight which rarely lets me down and does a decent job on high transconductance tubes, like 6DJ8s which the Hickok 600A doesn't. I'm very familiar with the vagaries of the market and have on more than one occasion refunded tubes that the buyer claim didn't test well on another tester only to have them test fine here and get resold to another who was delighted with them.
Basically, I''m just looking for opinions between these two to determine which one to keep and restore as both have much going for them.
 
Hiya,

539A is harder to find data for certain tubes and it takes up valuable desk space.

I have used and still have both (Well the 539A was replaced by a 539B) and my TV-7D/U is used more.

Frannie
 
forgive my ignorance but, what is it that makes the TV-7 so desireable?
Military? how it tests? Its manufacturer?
a curious mind needs to know.
thank you.
 
Testing tubes is an interesting situation, as there definitely is a hierarchy among testers, but ironically all seem to agree that the only real test is in the circuit as arts mentioned several posts back.
That being said, the TV-7 and Hickok 539 series are very highly thought after. I just opened the TV-7 is that puppy is BUILT. Here's some pics I just sent Kegger. Not mine, but you get the drift



DSCF8381-TV-7D.jpg






Here's an interesting overview on the Hickoks

http://www.tubewizard.com/recommended_Hickok_testers.htm

Hopefully, others who are much more authoritative on testers will chime in
 
After reading the link I realize I already have 2 of the best HICKOKS which are the same as the TV7.
The 533 and the 600. Just not mil construction.
So I'm a happy camper.
 
I wood choose the tester in the best condition and or the one that shows it has been used less, as all three are Hickok type testers and are more or less the same. The TV-7 is the best built of the three unless some butcher has been inside it.
 
From what I've read, the 600A is the lesser here due mainly to a +/- 15% variance in it's accuracy and something in it's scales. The 539 has two trannys for steady power and you set bias and filament via separate circuits. Also, there's distinct circuits for all three scales which leads to more accuracy. I'm not sure what the circuitry is in the TV7, but it is built from top quality components. It gives results as number between 0-120 with a minimum good, where the 539s read micromhos and use an average of new number for their baseline.

I need to get inside the 539 today and see what's up and report back. Both look to be excellent testers, which makes this a hsrd choice, but so far the TV7 seems to be getting the love.
 
Hiya,

FYI and not affliated.

As stated here by S-Petersen.

Dan Nelson is one heck of a TV-7 repair/calibration wizard enough so I would stick with the TV-7

You will see what I mean the first time you deal with him. He is a absolute treasure.

The TV-7D/U is the desirable model FYI and the TOTL of that model.

The 539A is nice but again its not the best one because the 539B/539C are much better than it as far as data and construction.

Am I telling you to stick with the TV-7D/U ??

Yep I am.

FYI:: They have conversion charts for the 0-120 to Micromhos freely available on the net. And a very nice modern Excel Chart with most every tube in it the TV7 can test.

Frannie
 
I have a Bell System version of the 539. It replaced my 600A. (I've also owned both B&K 707 & 747 (nice machines) and briefly an I-177 which I've never figured out why I bought it.) I have the full set of test data for the 539 which includes obsolete (battery tubes such as 01A), European (KT88, etc.), Western Electric (205D, 271A, etc.), plus what's on the roll chart which covers industrial. So far I've been able to test any tube I've come across and cannot see the 539 leaving anytime soon.

But, I've never owned a TV-7 either. My usual thinking when in this situation is repair both, sell off the one you don't like as much. If you got into both testers right, you should be able to offset repair costs for both with the sale of one. Or, get the 600A calibrated and just carry on. It's a great machine! I really don't use my 539 variant that much deeper than my 600A anyway. As far as 539 series glitches, make sure the fuse bulb has good connections. It is a common failure point.
 
Sell the 600 and figure out which one works better between the TV7 and 539 and sell the one that works less best. You said you already have a Knight as an emissions backup so you don't really need more than one trans-tester unless you have the space and extra time and money to maintain it.
 
I popped the hood on the 539A today and found enough wrong that I've decided to part with it an get the TV-7 restored. The 539A won't light tubes and the line meter is definitely messed up as I can jumper it with my multi-meter and get readings, and those pretty much make this a deal breaker. The Pilot lamp also doesn't light, but that's due to a broken wire I can't determine where to retap off the tranny/filament selector. I really wish I knew enough to see if I can get the meter to work, as that's a valuable part, but as far as which to keep, the TV-7 appears to be in much better shape and is garnering the bulk of the votes, so it looks like I'll be shipping it off to Dan in the near future.

Thanks to all for your input and guidance; I appreciate it!! :thumbsup:
 
After have both 539C and tv-7 for years I sold the 539c, The TV-7, its compact, built like a tank, many resources for tube data and there are very good qualified persons to calibrate them. The most important issue is meter replacement, all 3 meters on my 539C, were not to spec. All three had to be replaced, very hard to find those meters and so expensive with the tv-7 theres only one meter to replace and new replacements are available on ebay.
 
I bought the other testers because I sell tubes and wanted one with better "authority" than the Hickok 600. I wound up selling the 539 and had the TV-7DU calibrated, but it is flaking out on me a bit now, so I'm using a Knight emissions tester now.

The Knight isn't fancy, but it has proven time and again to both me and Kegger to deliver accurate readings, so for the tube sorting i'm doing now; it works just fine. Plus it can verify shorts in 6BQ5s, something that freaks out the TV-7DU.
 
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I'd keep the 600A no matter what, it's light portable and good for loaning to friends, I would also keep one or the other of the big ones as my main tester. Right now I use a 534a as a main tester and a 600, as a loaner and sanity check. The 600 is light and the knobs turn 360 degrees which I like. Which tester do you like? Keep that one.
 
I also sold the Hickok 600, as the Knight 600 really does do a good job. The Hickok has issues reading high transconductance tibes like 6DJ8/6922s. I know folk who were ready to pitch bunches until they tested them on other testers...
 
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