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Tube Tester Calibration Needed



 
 
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  #1  
Old September 13th 15, 09:05 PM posted to rec.audio.tubes
Balekan
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Default Tube Tester Calibration Needed

Well, I had my Triplett 3444 calibrated by Chris Haedt before he passed, God rest his soul. I am now in need of a fresh calibration. Can you folks direct me to who us radio enthusiasts are now trusting with our testers? Any and all help is greatly appreciated!

Mike
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  #2  
Old September 14th 15, 11:56 AM posted to rec.audio.tubes
Peter Wieck
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Posts: 2,418
Default Tube Tester Calibration Needed

On Sunday, September 13, 2015 at 4:05:55 PM UTC-4, Balekan wrote:
> Well, I had my Triplett 3444 calibrated by Chris Haedt before he passed, God rest his soul. I am now in need of a fresh calibration. Can you folks direct me to who us radio enthusiasts are now trusting with our testers? Any and all help is greatly appreciated!
>
> Mike


Mike:

What makes you think that you need a calibration? There are two very long-lived tubes in that beast (12AU7 & 6C4) that, unless they are seriously worn out, you should experience no drift in calibration for their (reasonable) life.

However, I did look through the manual for that unit ( http://www.triplett..com/wp-content/...2/11/84-96.pdf ) and there is one (1) adjustment for calibration. If you are adept with tubes - implied by owning and using such a tester - and if you have a reasonably accurate VOM (most are, these days), you can do it yourself fairly easily.

In any case, I suggest the following moving forward, and whether you do the calibration yourself or send it out: Once done, pick a couple of basic triode tubes, perhaps an 80 and a 45 (one rectifier and one power tube), or a basic pentode powere tube such as, perhaps, an EL84. Test them. Mark the reading(s) on the tube with a Sharpie. Put these tubes _away_ in a safe place. Every so often, after a few hundred hours of use, re-test the tubes. The reading(s) should be very nearly identical. THESE will become your indicator/test tubes.

I keep a Hickok 539B, and after going through the calibration process, once, I have a 6L6 and an 80 that I tested over twenty (20) years ago. No drift..

On the other hand, if you are anywhere near Kutztown this Friday/Saturday for the big show, bring your tester to the club table, and I would be glad to run through the calibration for you. You MUST let me know before the end of today (Monday) as I will need to cobble up the dummy load required for the test.

Peter Wieck
Melrose Park, PA
  #3  
Old September 14th 15, 06:09 PM posted to rec.audio.tubes
Balekan
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Posts: 6
Default Tube Tester Calibration Needed

On Monday, September 14, 2015 at 3:56:02 AM UTC-7, Peter Wieck wrote:
> On Sunday, September 13, 2015 at 4:05:55 PM UTC-4, Balekan wrote:
> > Well, I had my Triplett 3444 calibrated by Chris Haedt before he passed, God rest his soul. I am now in need of a fresh calibration. Can you folks direct me to who us radio enthusiasts are now trusting with our testers? Any and all help is greatly appreciated!
> >
> > Mike

>
> Mike:
>
> What makes you think that you need a calibration? There are two very long-lived tubes in that beast (12AU7 & 6C4) that, unless they are seriously worn out, you should experience no drift in calibration for their (reasonable) life.
>
> However, I did look through the manual for that unit ( http://www.triplett.com/wp-content/u...2/11/84-96.pdf ) and there is one (1) adjustment for calibration. If you are adept with tubes - implied by owning and using such a tester - and if you have a reasonably accurate VOM (most are, these days), you can do it yourself fairly easily.
>
> In any case, I suggest the following moving forward, and whether you do the calibration yourself or send it out: Once done, pick a couple of basic triode tubes, perhaps an 80 and a 45 (one rectifier and one power tube), or a basic pentode powere tube such as, perhaps, an EL84. Test them. Mark the reading(s) on the tube with a Sharpie. Put these tubes _away_ in a safe place. Every so often, after a few hundred hours of use, re-test the tubes. The reading(s) should be very nearly identical. THESE will become your indicator/test tubes.
>
> I keep a Hickok 539B, and after going through the calibration process, once, I have a 6L6 and an 80 that I tested over twenty (20) years ago. No drift.
>
> On the other hand, if you are anywhere near Kutztown this Friday/Saturday for the big show, bring your tester to the club table, and I would be glad to run through the calibration for you. You MUST let me know before the end of today (Monday) as I will need to cobble up the dummy load required for the test.
>
> Peter Wieck
> Melrose Park, PA


Hi Peter,

Thank you for such a generous offer! I wish I lived nearby, I am on the west coast. I would like to talk with you more though, do you have a way I can reach you directly?

Mike
  #4  
Old September 14th 15, 06:29 PM posted to rec.audio.tubes
Peter Wieck
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Posts: 2,418
Default Tube Tester Calibration Needed

On Monday, September 14, 2015 at 1:09:37 PM UTC-4, Balekan wrote:

Mike:

My direct e-mail (remove spaces, add proper symbols) is:

p f j w at a o l dot c o m

That should be much faster than this venue.

Peter Wieck
Melrose Park, PA
  #5  
Old September 15th 15, 01:06 AM posted to rec.audio.tubes
Big Bad Bob
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Posts: 351
Default Tube Tester Calibration Needed

On 09/13/15 13:05, Balekan so wittily quipped:
> Well, I had my Triplett 3444 calibrated by Chris Haedt before he passed, God rest his soul. I am now in need of a fresh calibration. Can you folks direct me to who us radio enthusiasts are now trusting with our testers? Any and all help is greatly appreciated!


you've given me an interesting idea...


long ago I had an 'emissions' style tester with the usual 3-position
switches on it, and a big paper roll with all of the switch positions.
I bought it at a swap meet for something cheap. [unfortunately I got
rid of most of my really old test gear for various reasons, "no room"
being a big one].

OK from what I'm reading, on sites like THIS one:

http://www.audiotubes.com/tubetest.htm

there are some really GOOD testers out there that put the device under a
REAL test, not just an emissions test with grids+plate tied together
like a diode. I would guess THAT kind of test might even be bad for the
tube under some conditions, drawing ANY kind of current on G1 being one
of them.


I'm guessing yours is one of those "good ones".


However... if you've got a good tube book handy with the standard curves
in it, a test COULD be devised for the types you typically want to test,
maybe saved in a database or something (pins with voltage levels and
currents), and some 'more modern' device could THEN run the test, under
microprocessor control.


Generating voltages and measuring currents would be trivial things to do
with a microcontroller, given the proper external parts.


It might be a fun project (even if I'm the only one in the world who'd
want something like this).

You'd first do a pin-pin conductivity check, then energize the heater
[testing surge/run current to make sure it's not shorted or damaged],
let the tube warm up, then apply test voltages in a reasonable order,
and measure the resulting cathode current.

Something like that is relatively easy for a microcontroller [been
there, done that], again with the proper external parts. Even something
simple like an Arduino could do it.


Biggest problems would be testing larger tubes like KT88 (or something
similar) since the max current on those is ~400ma (0V g1, 300V g2, 66V
plate, I checked the operating curves).


Anyway this is just a mental exercise at the moment. But it might cost
less to build (in parts, not time) than what the guy on that web site I
mentioned above is asking for HIS tube testers ($500 or so each I guess)

it might also be useful to find (or verify) 'matched pairs'. or print
up the actual operating curves.


[some time ago I saw a web page where someone made his own tubes,
hand-blown glass and everything - it was on a video. He did curve
testing afterwards to verify the operating characteristics, with
professional gear, probably expensive]


  #6  
Old September 15th 15, 01:54 PM posted to rec.audio.tubes
Peter Wieck
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Posts: 2,418
Default Tube Tester Calibration Needed

On Monday, September 14, 2015 at 8:07:04 PM UTC-4, Big Bad Bob wrote:

>
> you've given me an interesting idea...
>


Much snippage.

There are several digital tube testers out there, and even a few that connect to a PC or laptop. Some use existing technology - outboard additions to a Hickok Cardmatic, for example, and some that are stand-alone products. Some are incredibly sophisticated, far beyond the actual need, but for those who believe in them, quite nice. A few here, with reviews:

http://www.jacmusic.com/Tube-testers...pare-Index.htm

http://www.tubesontheweb.com/matic.htm

None of them cheap. If you could come up with a practical DIY solid-state tube tester with the ability to show performance curves and at a reasonable cost, likely you will do quite well. Software is available for existing hardware, you may even be able to derive that as well without having to program from scratch. Given the thousands of tube variants with many levels of "Quality" within each family, and to satisfy many irrational expectations, your software would have to be very robust.

Of course, we are discussing vacuum tubes here - devices that are about as variable as ears of corn, and not hardly precision devices. Generally, I try to explain to tube enthusiasts that there is only one valid test for a tube - and that is the piece of equipment it goes into. A tester will tell one a little bit about *that* tube on *that* tester at *that* moment, but it is only indicative, not fully predictive, of how it will work in-circuit. If you could better that consistently, you would really have something. Take the 6AQ8 detector tube as one example. I have two Dynaco FM3 tuners and several 6AQ8s. Two (2) will work fine in both tuners. Three (3) will work fine in one or the other tuner, but not both. Put the wrong tube in the tuner, and it is silent, full-stop. *ALL* of them test just fine on my Hickok 539B. Go figure, and such are the mysteries of the Vacuum Tube.

The 539B is one of the 'better' vintage testers, and mine is properly calibrated - but nothing is perfect.

http://jimmyauw.com/wp-content/uploa...ickok-539b.jpg

All those knobs, bells, whistles and adjustments are impressive, and it *can* match tubes with the use of an outboard VOM, but it still will not explain why a tube that tests just fine will not work in one item, and work fine in another.

Again, if you can solve that mystery reliably, the world will beat a path to your door!

Peter WIeck
Melrose Park, PA
  #7  
Old September 16th 15, 12:09 AM posted to rec.audio.tubes
Big Bad Bob
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Posts: 351
Default Tube Tester Calibration Needed

On 09/15/15 05:54, Peter Wieck so wittily quipped:
> On Monday, September 14, 2015 at 8:07:04 PM UTC-4, Big Bad Bob wrote:
>
>>
>> you've given me an interesting idea...
>>

>
> Much snippage.
>
> There are several digital tube testers out there, and even a few that connect to a PC or laptop.


> None of them cheap. If you could come up with a practical DIY
> solid-state tube tester with the ability to show performance curves
> and at a reasonable cost, likely you will do quite well.


so not entirely NEW idea, but I like making things *cheap* and
*available* for experimenters, so yeah.

thanks, I'll consider this more seriously then!


  #8  
Old May 13th 16, 09:41 PM posted to rec.audio.tubes
[email protected]
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Posts: 2
Default Tube Tester Calibration Needed

We rebuild and calibrate the Triplett 3444, and offer a modification by adding a digital plate current meter so you can read up to 199.9 ma at the same time as you test for gm, no switching required. It will also measure the actual current for diodes and rectifiers which the 3444 can not do now.

We modify the 3444 to be able to use 121vac to 124vac, from the original 117vac.

It takes a full week to do this work, every part is measured, three days just to calibrate the line, 72 hours to burn-in the new parts. Triple calibrated. We can think of no tester or analyzer which requires a long burn-in and absolute fine tuning like the 3444. They leave here with less than 1% error from specification. Calibration is good for a minimum of 5,000 hours of actual in-service use, that is more than ten years for most.

We have the original factory floor master 18 page calibration with notes, and the calibration docs. on the web are not accurate.

Chris was a good friend.

regards
Bud Allen
  #9  
Old May 13th 16, 09:47 PM posted to rec.audio.tubes
[email protected]
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Posts: 2
Default Tube Tester Calibration Needed

On Tuesday, September 15, 2015 at 5:54:07 AM UTC-7, Peter Wieck wrote:
> On Monday, September 14, 2015 at 8:07:04 PM UTC-4, Big Bad Bob wrote:
>
> >
> > you've given me an interesting idea...
> >

>
> Much snippage.
>
> There are several digital tube testers out there, and even a few that connect to a PC or laptop. Some use existing technology - outboard additions to a Hickok Cardmatic, for example, and some that are stand-alone products. Some are incredibly sophisticated, far beyond the actual need, but for those who believe in them, quite nice. A few here, with reviews:
>
> http://www.jacmusic.com/Tube-testers...pare-Index.htm
>
> http://www.tubesontheweb.com/matic.htm
>
> None of them cheap. If you could come up with a practical DIY solid-state tube tester with the ability to show performance curves and at a reasonable cost, likely you will do quite well. Software is available for existing hardware, you may even be able to derive that as well without having to program from scratch. Given the thousands of tube variants with many levels of "Quality" within each family, and to satisfy many irrational expectations, your software would have to be very robust.
>
> Of course, we are discussing vacuum tubes here - devices that are about as variable as ears of corn, and not hardly precision devices. Generally, I try to explain to tube enthusiasts that there is only one valid test for a tube - and that is the piece of equipment it goes into. A tester will tell one a little bit about *that* tube on *that* tester at *that* moment, but it is only indicative, not fully predictive, of how it will work in-circuit. If you could better that consistently, you would really have something. Take the 6AQ8 detector tube as one example. I have two Dynaco FM3 tuners and several 6AQ8s. Two (2) will work fine in both tuners. Three (3) will work fine in one or the other tuner, but not both. Put the wrong tube in the tuner, and it is silent, full-stop. *ALL* of them test just fine on my Hickok 539B. Go figure, and such are the mysteries of the Vacuum Tube.
>
> The 539B is one of the 'better' vintage testers, and mine is properly calibrated - but nothing is perfect.
>
> http://jimmyauw.com/wp-content/uploa...ickok-539b.jpg
>
> All those knobs, bells, whistles and adjustments are impressive, and it *can* match tubes with the use of an outboard VOM, but it still will not explain why a tube that tests just fine will not work in one item, and work fine in another.
>
> Again, if you can solve that mystery reliably, the world will beat a path to your door!
>
> Peter WIeck
> Melrose Park, PA




OK...here is you answer to your mystery. High impedance circuits are sensitive to leakage; AGC, PLL, FM, etc. If the tube has inner element leakage, the circuit may or may not work.

Bud
  #10  
Old May 15th 16, 09:38 PM posted to rec.audio.tubes
Big Bad Bob
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Posts: 351
Default Tube Tester Calibration Needed

On 05/13/16 13:47, so wittily quipped:
> On Tuesday, September 15, 2015 at 5:54:07 AM UTC-7, Peter Wieck wrote:
>> On Monday, September 14, 2015 at 8:07:04 PM UTC-4, Big Bad Bob wrote:
>>
>>>
>>> you've given me an interesting idea...
>>>

>>
>> Much snippage.
>>
>> There are several digital tube testers out there, and even a few that connect to a PC or laptop. Some use existing technology - outboard additions to a Hickok Cardmatic, for example, and some that are stand-alone products. Some are incredibly sophisticated, far beyond the actual need, but for those who believe in them, quite nice. A few here, with reviews:
>>
>>
http://www.jacmusic.com/Tube-testers...pare-Index.htm
>>
>> http://www.tubesontheweb.com/matic.htm
>>
>> None of them cheap. If you could come up with a practical DIY solid-state tube tester with the ability to show performance curves and at a reasonable cost, likely you will do quite well. Software is available for existing hardware, you may even be able to derive that as well without having to program from scratch. Given the thousands of tube variants with many levels of "Quality" within each family, and to satisfy many irrational expectations, your software would have to be very robust.
>>
>> Of course, we are discussing vacuum tubes here - devices that are about as variable as ears of corn, and not hardly precision devices. Generally, I try to explain to tube enthusiasts that there is only one valid test for a tube - and that is the piece of equipment it goes into. A tester will tell one a little bit about *that* tube on *that* tester at *that* moment, but it is only indicative, not fully predictive, of how it will work in-circuit. If you could better that consistently, you would really have something. Take the 6AQ8 detector tube as one example. I have two Dynaco FM3 tuners and several 6AQ8s. Two (2) will work fine in both tuners. Three (3) will work fine in one or the other tuner, but not both. Put the wrong tube in the tuner, and it is silent, full-stop. *ALL* of them test just fine on my Hickok 539B. Go figure, and such are the mysteries of the Vacuum Tube.
>>
>> The 539B is one of the 'better' vintage testers, and mine is properly calibrated - but nothing is perfect.
>>
>> http://jimmyauw.com/wp-content/uploa...ickok-539b.jpg
>>
>> All those knobs, bells, whistles and adjustments are impressive, and it *can* match tubes with the use of an outboard VOM, but it still will not explain why a tube that tests just fine will not work in one item, and work fine in another.
>>
>> Again, if you can solve that mystery reliably, the world will beat a path to your door!
>>
>> Peter WIeck
>> Melrose Park, PA

>
>
>
> OK...here is you answer to your mystery. High impedance circuits are sensitive to leakage; AGC, PLL, FM, etc. If the tube has inner element leakage, the circuit may or may not work.
>
> Bud
>


this makes sense as one possible explantion, sure. there's also THIS
[which leads to possible intolerance of component value changes over
time, and tube curve performance changes]:

https://en.wikipedia.org/wiki/Muntzing

so taking out extra components that IMPROVE RELIABILITY or SENSITIVITY
cuts down on price, sure, but at the expense of 'you can imagine what'.


one of the first 'victims' that seriously fell to Muntzing is the
simplified color demodulator circuits that became EXTREMELY popular in
the 60's and 70's on just about every color TV model, because there was
"no perceptible difference" (or so they say).

I didn't even know about this until recently, when I saw a schematic for
the color demod (with explanation) in a very OLD TV set, that had
multiple tubes involved (all multi-element tubes too). No 'grounded
grid cathode feed' for the green demod on THAT one. It was all
separated, like an 'ideal demodulator' would be, and re-combined with a
resistor matrix to form the tri-color signal. The 'Muntzed' version has
a single 3 element common cathode tube with phase shifters [as I
recall], driving the common cathode with the amplitude signal, one grid
with the Red phase-shift signal, and another grid with the Blue
phase-shift signal [the result is a somewhat-balanced phase demodulator,
which typically will be a single compactron tube especially designed for
this, with 3 triodes - output drives the color grids, and the color
picture tube cathode gets the 'luma' signal directly, resulting in
'color TV']. In this case, green is assumed to be 'in phase' (adjusted
by the 'tint' control), and the other 2 colors have fixed phase shifts
applied so they phase-demodulate properly. The result gives you an
APPROXIMATE demodulation, but "good enough" for Muntzing, with a LOT
fewer parts. And so, there you have it.

for how it's done "old style", check this out:
http://www.antiqueradio.org/RCACT-10...sionDesign.htm

"Color Demodulation 2.x" section describes how the newer method works

[I expect that by the 1980's, solid state sets used color demodulator
ICs that did things "correctly" since it's cheap/small to build silicon
with a zillion active components on it, unlike a handful of tubes
compared to just one].


 




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