Author Topic: Dirt cheap and simple scope-based component tester - curve tracer  (Read 96013 times)

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Offline w2aewTopic starter

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<shameless self promotion  ;)>

I posted a new video that shows an old idea for simple component testing / curve tracing using an oscilloscope and just a few components.  Circuits of this type have literally been around for decades, and are often referred to as an Octopus component tester.  I really don't know the origin of the name.  You can Google various search terms like octopus component tester curve tracer, etc. and find dozens of variants. 

The video basically shows how this simple technique works, and demonstrates with some examples.  Enjoy:


Alan - W2AEW
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Offline TerminalJack505

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #1 on: June 09, 2012, 08:46:04 pm »
I love your videos!  I had never heard of this circuit before.
 

Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #2 on: June 09, 2012, 11:20:07 pm »
Nice video, thanks.

I first built an 'Octopus' whilst at Maritime College in the late 1980's. As you say, they have been around a long time and are often home built as so few parts are needed and they work so well on semiconductors.

Whilst working for my employer I was trained to use the Huntron Tracker instruments. For those who don't know, these are an 'Octopus' combined with a scope display to produce an all-in-one instrument for testing components. The Huntron units add a little to the design by having several voltage/current ranges to suit differing scenarios. They are very useful bits of kit, especially when hunting a fault on a PCB and you have a known good PCB as a reference to compare to. I bought a couple of used Huntron HTR1005B-1S a few years ago at a very reasonable price. Prices have sky rocketed since then so the word must be out that these are good units.

The Hameg oscilloscopes used to include an 'Octopus' mode in their design, named a Component Tester mode (CT for short). I have always thought them forward thinking to have done so. You can often pick up an HM203 series 20MHz CRO for a very low price or even free if you are lucky... if you do, you get a simplified version of the Huntron Tracker included for free !

Tektronix used to sell a advanced 'Octopus' I/V component tester under the model no. TR210....it was in fact made by Huntron and also sold under their model no. HTR-200. The unit was designed to connect to the TDS200 series DSO's in order to provide a component testing capability. It was far more advanced than the simple Octopus, HTR-1005B-1S or Hameg CT. I managed to pick one up a couple of years ago quite cheaply. If you see one at a decent price, you should consider buying it as it is a very refined piece of test kit with special low voltage/low current modes to suit modern low voltage MOS technology.

A word of warning..... Huntron carried out tests on TTL and CMOS technology to prove that the 50V test pulse that the Tracker could generate would not destroy the component under test. Huntron advise the use of the lower voltage ranges, but succeeded in proving that the chips tested still worked. It is interesting to note that Huntron later released the 2000 series that had more ranges and lower test voltages but these are still considered risky if used on very low voltage MOS components. The TR210/HTR-200 and later models all provide very low test voltage modes for VLV MOS and even have a special range lockout function to prevent accidental activation of the higher voltage ranges. Me thinks Huntron are not confident that the latest low voltage technology will take kindly to the older Huntron/Octopus excitation voltages. Be careful regarding this point if you DIY an Octopus for use on sensitive low voltage MOS technology.

The topic of this thread is 'Dirt Cheap' and none of the units I have mentioned, except the Hameg scope, could be considered cheap. A chap in the USA decided to build and market a cheaper solution. Take a look here:

 http://www.actracer.com/

Whilst the unit is cheaper, I do not consider it cheap per se considering the component count but then this isn't a China made unit  ;) The ACtracer has a little bit more versatility than a basic Octopus and may be worth considering if the budget will stretch to it. Its certainly a lot cheaper than a new or used Huntron 2000 which it is trying to emulate.

Aurora
« Last Edit: June 09, 2012, 11:53:19 pm by Aurora »
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Offline digsys

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #3 on: June 09, 2012, 11:57:09 pm »
My Elektor (Heathkit) Transistor curve tracer, from 1980 I think, was my favourite test tool by far !!
I had the Hamegs, but they were no where near as nice. Being able to drive a transistor to destruction,
observing failure mode, then just backing off to recover ... multiple traces, sure miss it.
Hello <tap> <tap> .. is this thing on?
 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #4 on: June 10, 2012, 04:20:15 am »
Nice video, thanks.
<<<snipped>>>
Aurora

Aurora - awesome post, great information!  I was aware of the Huntron units, and the Hameg scope with the CT option.  That is similar to the Heath scope that I showed in my video, and I've also seen the same scope under other names.  However, I did not know about the Tektronix/Huntron unit - and I work for Tektronix!  Of course, I didn't for for them 14 years ago when this was a product.  Very interesting!

Thanks for watching and posting.
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Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #5 on: June 10, 2012, 09:37:46 am »
I am glad my posting was of interest.

If anyone wants to see the user manual, service manual or schematics for the TR210 I will be happy to provide them as I have the full set. Huntron provided the schematic and offer excellent support for their older products.

As a sort of 'spin-off' from the Huntron Tracker, Polar Instruments produced a component tester that offered very similar capabilities PLUS a curve tracer function for transistors. I bought it out of curiosity as I use Polar Tone Ohm's and had not seen the component tester before.

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Offline SeanB

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #6 on: June 10, 2012, 09:47:40 am »
Interested in that, I can build it into a old Tek frame I have. The scope side works, but the medical recorder it had died a long time ago. Was looking to do this for a while.
 

Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #7 on: June 10, 2012, 10:17:01 am »
Digsys,

Not quite the Elektor unit that you may have had, but take a look here:

http://www.ebay.co.uk/itm/Power-Transistor-Curve-Tracer-adapter-XY-Oscilloscopes-/140547987228?pt=BI_Oscilloscopes&hash=item20b950171c

The curve tracer is in fact a copy of an Elektor design with minor mods and is so cheap that I bought two to experiment with. I have not had time yet but you may want to buy one for experimentation as well, its certainly cheap enough  :)

The schematic is provided and I have attached it to this message. The original 1989 Elektor design from which it was taken is available on the Internet.
I attach it as an advertisement for Elektor but will remove it if asked. Its is VERY old though  ;)


Elektor has a new Curve Tracer design, as can be seen here:

http://www.elektor.com/magazines/2009/february/transistor-curve-tracer.810360.lynkx


Aurora
 
« Last Edit: June 10, 2012, 10:42:45 am by Aurora »
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Offline caroper

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #8 on: June 10, 2012, 10:21:38 am »
You can also do this with a PC and a simple hardware interface that buffers the sound card.
Here are 2 articles on the subject published by Dr George R. Steber, WB9LVI, they cover the same ground but one goes more into the theory the other is about the hardware.


The 3rd file is from a user of the earlier design, I include it as he provides a PCB layout for those who wish to take it beyond the breadboard.


Cheers
Chris

Edit:
The software is here: http://www.arrl.org/files/file/QEX%20Binaries/06_July/7x06Steber.zip
Works on WIN 7 64 Bit and WIN XP, I have not tested on WIN 8 but it should work.
« Last Edit: March 20, 2014, 11:13:47 pm by caroper »
 
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Offline SeanB

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #9 on: June 10, 2012, 10:32:43 am »
Thanks.
 

Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #10 on: June 10, 2012, 10:53:13 am »
Here is some more information on using I/V curve analysis units on components.
I also attach the Huntron US Patent for the original 'Tracker' design.
The schematics and service manuals for many of the Huntron Trackers are available FOC from several sites in the internet.

Aurora

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Offline digsys

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #11 on: June 10, 2012, 12:17:05 pm »
Quote
Not quite the Elektor unit that you may have had ...
Thanks. I have often searched for the original kit from ~1980. It came with nice sloping front metalwork and nice decals.
The PCB also had a lot more parts, took me ages to assemble, if my memory is any good. Elektor were so ahead of their time.
Quote
Elektor has a new Curve Tracer design, as can be seen here
Saw that, not as impressed. Maybe I'm too cynical these days :-)
Hello <tap> <tap> .. is this thing on?
 

Offline JuiceKing

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #12 on: June 10, 2012, 10:26:48 pm »
This is a great video for beginners. And I just watched another four or five. Your videos go right to the heart of the questions that have been bugging me and strike just the right mix of theory and demonstration. Please keep them coming. I just watched "Use a scope to measure the length and impedance of coax" and with it I feel I much better understand characteristic impedance, termination, etc. Thanks!!
 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #13 on: June 11, 2012, 01:40:22 am »
This is a great video for beginners. And I just watched another four or five. Your videos go right to the heart of the questions that have been bugging me and strike just the right mix of theory and demonstration. Please keep them coming. I just watched "Use a scope to measure the length and impedance of coax" and with it I feel I much better understand characteristic impedance, termination, etc. Thanks!!

Ken - thank you!  I'm glad I'm hitting the "sweet spot" with you.  Please feel free to shoot me a message with ideas for video topics that you'd like to see.

Alan
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Offline billclay

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #14 on: June 11, 2012, 04:38:22 am »
IET also made a curve tracer.  It was the STS-1600.

The display was LCD dot matrix, and it is rather slow to update, but it does work.
 
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Offline george graves

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #15 on: June 11, 2012, 07:04:54 am »
Love the video - it was so easy to follow along.  Really great stuff.

Is there any reason why I can't use a function generator to generate the test signal?

Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #16 on: June 11, 2012, 08:14:30 am »
George,

If you take a look at the "ACTracer FG" webpage link that I provided earlier in the thread, you will see that the designer of that unit has added the capability of an external function generator as the excitation oscillator. The ability to change frequency is useful when testing capacitors of varying values.

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Offline opticpow

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #17 on: June 11, 2012, 08:18:57 am »

The Hameg oscilloscopes used to include an 'Octopus' mode in their design, named a Component Tester mode (CT for short). I have always thought them forward thinking to have done so. You can often pick up an HM203 series 20MHz CRO for a very low price or even free if you are lucky... if you do, you get a simplified version of the Huntron Tracker included for free !


I'm happy to say that the current series Hameg Scopes still include the component tester as standard as can be seen on my HMO724.

Cheers,

Wayne.
 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #18 on: June 11, 2012, 12:40:22 pm »
Love the video - it was so easy to follow along.  Really great stuff.

Is there any reason why I can't use a function generator to generate the test signal?

George - in this very simple Octopus design, the only reason that you can't directly use a function generator is because the scope's Ground reference is not connected to either side of the signal generator (the transformer in this case).  On a function generator, the output is generally earth referenced.  Of course, you could use a transformer at the output of the function generator.

To tell the truth, I didn't have a 6.3V transformer as shown most online Octopus schematics, and I was playing with different test frequencies, so I was really using a my function generator to drive the secondary of the 12V transformer that is shown in the video, and the primary was driving the simplified circuit.  Thus, I was able to use very little drive from the function generator, since the transform stepped the voltage up.  I simply adjusted the amplitude on my generator as needed to get the output voltage I wanted.  The transformer provided the earth isolation so that I could use the junction of the DUT and current limit/sense resistor as the ground reference.
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Offline jackasspenguin

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #19 on: June 11, 2012, 01:32:16 pm »
Hmm, while I'm considering buying a filament power supply I'm trying to think of a way to use something I either already have or buy something more financially appropriate.  I'd love to build this. Although I would rather not have an 8lb iron core step down transformer to live with it. I mean in reality, if I had a filament transformer I'd rather build a tube amp to put it in. So my considerations would be something like this perhaps... This is a 220V input 12V AC output transformer, but wouldn't the output simply be half of whats rated? 110V ac input you'd get 6V AC out right? I Googled octopus component tester and what I found asks for 3 volts off the center tap of a 6V ac transformer.  I'm just not sure what values or component I'd need to tweak in order to conform the circuit to suit the power supply.  I'm not dead set on this power supply.  I just thought there may be something out there over the shelf that might be a better choice.  Johnny W :)

http://www.ebay.com/itm/20W-Max-220V-to-12V-AC-0-086A-Home-LED-Light-Power-Supply-Electronic-Transformer-/400303095053?pt=LH_DefaultDomain_0&hash=item5d33ec7d0d
 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #20 on: June 11, 2012, 03:06:54 pm »
Hmm, while I'm considering buying a filament power supply I'm trying to think of a way to use something I either already have or buy something more financially appropriate.  I'd love to build this. Although I would rather not have an 8lb iron core step down transformer to live with it. I mean in reality, if I had a filament transformer I'd rather build a tube amp to put it in. So my considerations would be something like this perhaps... This is a 220V input 12V AC output transformer, but wouldn't the output simply be half of whats rated? 110V ac input you'd get 6V AC out right? I Googled octopus component tester and what I found asks for 3 volts off the center tap of a 6V ac transformer.  I'm just not sure what values or component I'd need to tweak in order to conform the circuit to suit the power supply.  I'm not dead set on this power supply.  I just thought there may be something out there over the shelf that might be a better choice.  Johnny W :)

http://www.ebay.com/itm/20W-Max-220V-to-12V-AC-0-086A-Home-LED-Light-Power-Supply-Electronic-Transformer-/400303095053?pt=LH_DefaultDomain_0&hash=item5d33ec7d0d

There's really nothing set in stone with this.  Using a 220VAC - 12VAC transformer on 110VAC will indeed give you 6VAC out.  It's really up to you to decide how much AC voltage you want to use as your excitation voltage.  You can always use a voltage divider at the output to cut it down further, as most of the Octopus schematics show.  You can even use an audio isolation transformer on the output of a function generator if you want.  You are also free to choose what current limit/sense resistor you want to use.  My simplified example was used to simply show the concept.
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Offline mianchen

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #21 on: June 11, 2012, 04:07:53 pm »
Alan,

Thanks for the very informative / educational videos -  You've got a new Youtube subscriber.

I've tried your curve tracer with my Iwatsu ss-5705 today, it didn't work as expected. Sorry for my n00b question - is it because CH1 and CH2 are completely out of phase? I try to locate an 'invert' switch on the scope, but couldn't see anything. Does it mean that I have to build an inversion circuit to use my scope as a curve tracer?

Thank you in advance.

I've attached some pics:

Wave forms of CH1 and CH2 when connected to the 'Octupus'


X-Y Mode is on:



Measuring a capacitor



Measuring a diode

 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #22 on: June 11, 2012, 05:01:13 pm »
Really no need to build an inverting circuit.  Just recognize the fact that +current through your DUT is deflecting in the downward direction instead of up.  You're waveforms look OK, there's some phase shift beyond the 180 degrees due to the non-inverted ch2, but that could be inherent to the scope, and I wouldn't sweat it.  Looks like your scope doesn't have an Invert function on CH2 because it includes a Ch1-Ch2 feature.  Many other analog scopes have only a Ch1+Ch2 (ADD) feature, so the Ch2-INV was added so that you could also do the subtraction. 

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Offline tekfan

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #23 on: June 11, 2012, 05:10:35 pm »
I've tried your curve tracer with my Iwatsu ss-5705 today, it didn't work as expected. Sorry for my n00b question - is it because CH1 and CH2 are completely out of phase? I try to locate an 'invert' switch on the scope, but couldn't see anything. Does it mean that I have to build an inversion circuit to use my scope as a curve tracer?

Make sure that you have both inputs DC coupled. That should take care of the problem. You can invert the Y axis by pulling the channel B position control out (it's labeled PULL INV).

One can never have enough oscilloscopes.
 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #24 on: June 11, 2012, 06:20:39 pm »
I've tried your curve tracer with my Iwatsu ss-5705 today, it didn't work as expected. Sorry for my n00b question - is it because CH1 and CH2 are completely out of phase? I try to locate an 'invert' switch on the scope, but couldn't see anything. Does it mean that I have to build an inversion circuit to use my scope as a curve tracer?

Make sure that you have both inputs DC coupled. That should take care of the problem. You can invert the Y axis by pulling the channel B position control out (it's labeled PULL INV).

Excellent point about DC coupling - and nice catch on the pull-inv function - I missed that in the photos.  Sounds like you've got him all sorted now.
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Offline codeboy2k

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #25 on: June 11, 2012, 10:27:42 pm »
I've tried your curve tracer with my Iwatsu ss-5705 today, it didn't work as expected. Sorry for my n00b question - is it because CH1 and CH2 are completely out of phase? I try to locate an 'invert' switch on the scope, but couldn't see anything. Does it mean that I have to build an inversion circuit to use my scope as a curve tracer?

Make sure that you have both inputs DC coupled. That should take care of the problem. You can invert the Y axis by pulling the channel B position control out (it's labeled PULL INV).

Excellent point about DC coupling - and nice catch on the pull-inv function - I missed that in the photos.  Sounds like you've got him all sorted now.
When I first started out using a scope (... maybe 1972)... I used to think oh, I'm probing a DC signal, I better choose DC coupling. and for any AC signals, I always chose AC coupling.  I felt the scope would 'esplode if I ever got that messed up... then I learned what the AC/DC coupling button actually did :)
 

Offline george graves

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #26 on: June 11, 2012, 10:54:21 pm »
If you take a look at the "ACTracer FG" webpage

Thanks for the link - $100 is a bit more that I would care to drop.

I think I'll pick up a audio isolation transformer and see how it works with my FG - thanks for the tip on that.

So - will an electrolytic cap(before it it goes bang!...) will look like a big old "D" on the scope?

« Last Edit: June 11, 2012, 11:09:06 pm by george graves »
 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #27 on: June 12, 2012, 01:13:27 am »
When I first started out using a scope (... maybe 1972)... I used to think oh, I'm probing a DC signal, I better choose DC coupling. and for any AC signals, I always chose AC coupling.  I felt the scope would 'esplode if I ever got that messed up... then I learned what the AC/DC coupling button actually did :)

That's why I did a video on that a few months ago!
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Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #28 on: June 12, 2012, 01:14:43 am »

So - will an electrolytic cap(before it it goes bang!...) will look like a big old "D" on the scope?

If you limit your current to <<1mA, there will be no "bang"
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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #29 on: June 12, 2012, 10:37:25 am »
Hi

Excellent video - you have a new fan! George Graves has already asked the first question that popped into my mind (about using a function generator) - looks like I need to do some shopping for transformers. The other question that occurred to me when I was this was - could you do something similar to produce a voltage/voltage curve such as Dave J is showing here (skip to 5min 40sec)[1]:



or is that produced in a completely different way?

Regards
John

[1] I can't seem to get the video to start at a specific time - I've tried &t=05m40s and  &start=340
 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #30 on: June 12, 2012, 04:45:49 pm »
Hi

Excellent video - you have a new fan! George Graves has already asked the first question that popped into my mind (about using a function generator) - looks like I need to do some shopping for transformers. The other question that occurred to me when I was this was - could you do something similar to produce a voltage/voltage curve such as Dave J is showing here (skip to 5min 40sec)[1]:
or is that produced in a completely different way?


In the video I showed, the scope is actually showing voltage vs. voltage in the XY mode - it just so happens that the Y axis (the CH2 input) is probing directly across a fixed resistor, so the voltage is directly proportional to the current.  This is precisely what Dave is doing in his video (voltage across a resistor).  XY mode in the scope just plots the two signals against each other (usually Ch1 and Ch2).  So, in any circuit where you want to see the response of one voltage to another, simply put the scope in XY mode.
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Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #31 on: June 12, 2012, 05:17:15 pm »
George,

Reference the  ACTracerFG.....

I agree that the ACTracer-FG does not come under the 'Dirt Cheap' banner, but it is interesting to look at the design. The deigner originally used only an on-board signal source, but recently added the external Function Generator input. The PCB is well photographed, so it may be possible to work out how he has arranged the FG input without a transformer. I have meant to reverse engineer the basic circuit used but I haven't really got the motivation due to having the Huntron units.

Aurora
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Offline 0xdeadbeef

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Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #33 on: June 12, 2012, 05:51:09 pm »
Here is an interesting variant with adjustable test conditions for the DUT

http://www.techlib.com/electronics/curvetrace.html

Aurora
« Last Edit: June 12, 2012, 07:30:56 pm by Aurora »
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Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #34 on: June 12, 2012, 07:29:34 pm »
Awwwwww 0xdeadbeef, why'd you have to go and show me a portable I/V unit ..... I can't resist portable kit  :)  Thank you for the link.

My German isn't great but I managed to muddle my way through the ELV purchase process and I now have an ELV KT100 Kit on it's way to me in the UK. I bought the kit as the PCB is pre-populated with the SMD components and I think I'll enjoy constructing the remaining parts of it. Thank heavens the GBP has recovered a little against the Euro  :)

A portable unit will be very usefull when I don't want to lug around a mains powered Huntron or dual channel CRO/DSO. I found the manual for the unit here:

http://www.techome.de/manuals/58758_Komponententester_KT100_UM.pdf

The quality looks OK and I like the fact that I will have a schematic.

Aurora
« Last Edit: June 12, 2012, 07:32:12 pm by Aurora »
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Offline 0xdeadbeef

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #35 on: June 12, 2012, 08:53:05 pm »
Hey, just don't blame me if it sucks. The only user review says that it's working well but the LCD has little contrast even at the highest setting. Then again, maybe this can be tweaked a bit.
Trying is the first step towards failure - Homer J. Simpson
 

Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #36 on: June 12, 2012, 09:18:20 pm »
Here is an interesting variant with adjustable test conditions for the DUT

http://www.techlib.com/electronics/curvetrace.html

Aurora

This is a decent, more flexible variant of the original octopus idea.  The only downside I see to this design is that the voltage across the current sense resistor adds to the DUT voltage, thus adding to the apparent DUT resistance.  Not a big deal, but is a difference.  It therefore also allows for a grounded test signal source, like a function generator.
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Offline KD0CAC John

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #37 on: June 12, 2012, 09:47:52 pm »
Just to double check , some of the older analog scopes had the component test function / switch ?
Any chance the Rigol  DS1152E has that , I would guess in the menu somewhere if it does ?
And the curve tracer link , is that for scopes without the component test function ?
Just to confirm ?
Thanks
 
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Offline w2aewTopic starter

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #38 on: June 12, 2012, 10:23:19 pm »
Just to double check , some of the older analog scopes had the component test function / switch ?
Any chance the Rigol  DS1152E has that , I would guess in the menu somewhere if it does ?
And the curve tracer link , is that for scopes without the component test function ?
Just to confirm ?
Thanks

A small percentage of older analog scopes had this feature built in.  Most do not.  I don't think the Rigol has the feature.  Thus, the circuit shown in the video, or in the various links in this thread, or in a Google search for Octopus Component Tester:
https://www.google.com/search?sugexp=chrome,mod=19&sourceid=chrome&ie=UTF-8&q=octopus+component+tester
can be used with nearly any scope that has an XY mode (nearly all scope should have XY mode).

Confirmed?
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Offline KD0CAC John

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #39 on: June 12, 2012, 10:26:28 pm »
Thanks
At least all of these accessories do not take up much space as some gear .
 

Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #40 on: June 12, 2012, 10:36:48 pm »
0xdeadbeef,

Don't worry, I take responsibility for my own mistakes  ;)

There are two reviews...one for the built unit and one for the kit. The kit review says: "Very good and functional testers. First class components"

No mention of display issues and anyway these displays are now so cheap that I would fit a better one if needed  :)

Having looked at the schematic I believe it to be a pretty decent design and IMHO better value for money than the ACTracer as I get the benefit of total portability. If you were to look at Huntrons prices for an LCD display Tracker you would be horrified !

I don't like to waste money but this looks a pretty decent risk to me  :)

Thanks again for pointing me towards ELV. I have purchased from them before but had no idea that they could supply this unit.

Aurora
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Offline codeboy2k

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #41 on: June 13, 2012, 01:11:30 am »
I've always liked this curve tracer kit that I found several years ago, I bookmarked it, so I remembered it when this thread popped up.

I don't own this one, but the author/developer has done a nice job and it's had good reviews.  Sadly, he's not selling it anymore.

http://fullnet.com/~tomg/gooteect.htm

It wasn't cheap at $779 for the kit and $1200 fully assembled, but it included an audio function generator and triple output power supply.




 

Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #42 on: June 15, 2012, 02:53:32 pm »
The ELV K100 arrived today  :)

Initial impressions of the kit are very good indeed. Professionally packed and quality components used.

I attach the unpacking photos

Aurora
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Offline PlainName

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #43 on: August 28, 2013, 08:45:28 pm »
Quote
The ELV K100 arrived today

How did this turn out? Worth the money or a dead loss?
 

Offline KD0CAC John

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #44 on: August 28, 2013, 09:38:42 pm »
Aurora , also waiting to see your finished kit ?
I just noticed that other posts 2 ago are dated june 16 2012 , is this thread that old of a fluke over the net ?
 

Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #45 on: August 28, 2013, 10:09:39 pm »
Sadly serious illness has placed most of my projects on hold for the past 2 years.

I am eager to catch up with these projects now that my health is improving. This will be very high on my priority list but I am presently concentrating on repairing some thermal imaging cameras.

Thanks for resurrecting this thread. The reports from others who have built this unit has been favourable and the negative comments regarding screen contrast have been addressed by ELV which is good news. Its just a voltage setting.

Fraser
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Offline PlainName

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #46 on: August 28, 2013, 10:13:08 pm »
Oh, sorry to nudge you when you are not up to dealing with this. But good news that your health is improving.

Ummm... if it would help at all, I would be happy for you to ship the kit to me and I would be willing to try it out for you  ;)
 

Offline Fraser

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #47 on: August 28, 2013, 11:36:20 pm »
You have rekindled my interest in this project. I need a rest from squinting at tiny SMT devices in the thermal cameras, so this will be a good diversion. I will see if I get time over the next few days. Watch this space.

Fraser
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Offline eman12

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #48 on: August 28, 2013, 11:45:46 pm »
Thanks Alan For the Video.
How to start to learn Electronics in an easy mode:
 

Offline Alexei.Polkhanov

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #49 on: August 29, 2013, 01:35:20 am »
I wanted to get ID vs VGS (Drain current vs Gate to Source voltage) curve traced for several MOSFETS. I fugured that since all DMMs and Programmable power supplies have USB interface I can create curve tracer program on my PC. I wrote a program for MATLAB that sends commands to equipment and voila I have the trace at no additional cost if I don't count 2-3 hours of my time.

I think this method is much more flexible than using these special tracers unless they can be connected to computer to read raw data. If you have raw measurements you can add any imaginable plotting, scaling and post-processing very fast. What do I do with this plot on oscilloscope? Is it showing 3.4V pinch off voltage or 3.5V .... or something in between ?

Before that I was looking at component tester made by Peak Electronic Design. They have a "PRO" version that comes with plotting software: http://www.peakelec.co.uk/acatalog/dca75-dca-pro.html Then I realized that such device is limited to standard tests and more importantly it is limited by available battery power. I have to agree it probably saves a lot of time when you are going through your junk box.

 

Offline PlainName

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #50 on: August 29, 2013, 03:13:36 pm »
Quote
You have rekindled my interest in this project.

It is my pleasure, I assure you :)
 

Offline glicos

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #51 on: August 29, 2013, 04:35:14 pm »
Fluke also released such functionality in their GMM (Graphical Multimeter, Fluke 867B). This is one of the most useful function im using till now.....

 

Offline glicos

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #52 on: August 30, 2013, 05:13:00 am »
You can also do this with a PC and a simple hardware interface that buffers the sound card.
Here are 2 articles on the subject published by Dr George R. Steber, WB9LVI, they cover the same ground but one goes more into the theory the other is about the hardware.


The 3rd file is from a user of the earlier design, I include it as he provides a PCB layout for those who wish to take it beyond the breadboard.


Cheers
Chris

Hi Chris,

Do you still have the copy of the software? im interested in building this one..hope you got the software copy...thanks...

Edit: Thanks..i already found the software...for the benefit of others, i attached it here...

http://www.4shared.com/zip/xW0jIGsp/7x06Steber.html
« Last Edit: August 30, 2013, 05:24:39 am by glicos »
 

Offline casinada

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« Last Edit: August 31, 2013, 06:43:55 pm by casinada »
 

Offline M0BSW

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #54 on: August 31, 2013, 08:17:09 pm »
I am glad my posting was of interest.

If anyone wants to see the user manual, service manual or schematics for the TR210 I will be happy to provide them as I have the full set. Huntron provided the schematic and offer excellent support for their older products.

As a sort of 'spin-off' from the Huntron Tracker, Polar Instruments produced a component tester that offered very similar capabilities PLUS a curve tracer function for transistors. I bought it out of curiosity as I use Polar Tone Ohm's and had not seen the component tester before.
I wouldn't mind a copy of the schematic  if you post it on here.
no one would or will tell me how to delete this account
 

Offline caroper

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #55 on: March 20, 2014, 10:49:05 pm »
Edit: Thanks..i already found the software...for the benefit of others, i attached it here...
http://www.4shared.com/zip/xW0jIGsp/7x06Steber.html

And to save having to go via a 3rd Party, here original is the Software from the link in the PDF on the QEX magazine Server http://www.arrl.org/files/file/QEX%20Binaries/06_July/7x06Steber.zip
Out of interest for those worried, as I was, that this software dates from 2006, I can confirm that it runs perfectly on WIN 7-64Bit so probably will on WIN 8 too.

Cheers
Chris

Offline sweesiong78

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #56 on: October 13, 2014, 06:20:04 pm »
Hi, I built the octopus circuit according to the attached file diagram.

My scope is a Rigol 1054Z. My small problem is that I find that I have to invert BOTH X and Y channel in order to get the 'correct' shapes for the graphs.

I have checked my connections and I think they are correct. If I just invert the Y channel (vertical/current) input I get a mirrored image (along the x-axis), so for eg. for a resistor instead of a positive slope line I get a negative slope line. Does anyone have a clue whats going on? I can post screenshots from the scope later.
 

Offline mojoe

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #57 on: April 11, 2015, 07:16:34 am »
If anyone wants to see the user manual, service manual or schematics for the TR210 I will be happy to provide them as I have the full set. Huntron provided the schematic and offer excellent support for their older products.

Aurora, I know that this thread is  a bit old and it spans a few years. Is it still possible to get the TR210 schematic from you? I have the user and service manuals.

If you can't post it here, PM me and I'll give you an email address to send it to.

Thanks.
 

Offline OiD

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #58 on: April 27, 2016, 12:05:30 am »
Hey alan,
Thanks for the video, I've never stopped to think how the component test function worked (well actually I had, but I would've never of guessed it was so simple!). Brilliant! Just found out my DSO also has an XY mode (apparently called "versus"). Will miss the CRO built in tester... :P

I guess I'll need to find a nice little trasnformer and a write it down as another little project  :-+ I wonder if a variable frequency would be usefull, 50, 60, 100, 120, 400, 1000Hz... :-/O

Cheers!
 

Offline m3vuv

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #59 on: August 20, 2018, 11:30:53 pm »
just came accross this shame the link for the pc software is dead.
 

Offline qu1j0t3

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #60 on: November 03, 2018, 11:45:06 pm »
the link for the pc software is dead.

If you mean Steber's software? It's here: http://www.arrl.org/forum/topics/view/153
 

Offline IconicPCB

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #61 on: November 04, 2018, 12:13:15 am »
In the early eighties i worked at HP  Joseph Street repair and calibration facility in Blackburn ( a suburb of Melbourne).

A note came out showing how to use a HP45 wallwart to knock up a curve tracer simply using the transformer and a current limiting resistor.
 

Offline microMANIAC

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #62 on: November 06, 2018, 12:39:08 am »
My Elektor (Heathkit) Transistor curve tracer, from 1980 I think, was my favourite test tool by far !!
I had the Hamegs, but they were no where near as nice. Being able to drive a transistor to destruction,
observing failure mode, then just backing off to recover ... multiple traces, sure miss it.

Anybody else here miss some of those old Heathkit beasties?
 

Offline Wimberleytech

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Re: Dirt cheap and simple scope-based component tester - curve tracer
« Reply #63 on: November 06, 2018, 01:50:37 am »
Yup, built it in 1974 from this Popular Electronics Magazine.  And...I still have it...still works.
 


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