Show Us Your Curve Tracer

[Anthocyanina]

If someone is interested, I have a pdf of the original ELEKTOR article the Thai kit is based upon. Not that it is very diffiult to find but if someone wants it without much hassle, drop me a note.

I would like that, please, i think it would be fun to build a curve tracer. Thank you!

[Calambres]

Curve_Tracer_(ELEKTOR_12-89).pdf

[QuadESL63]

My Philips PM6507 curve tracer:

Jac

[Calvin]

Hi,

regarding the locky-z intelligent curve tracer I had a bit of time to test it again.
Seemingly his own software rev.3.1 generated the problems on my system.
The now installed rev 3.5 which user erikovsky put on github seems better.
At least I could get some MOSFET measurements to look almost like MOSFET curves.

regards
Calvin

[jastreb]

Where did you buy that transistor holder. Love it

[mjs]

Some years ago I bought a boatanchor HP 4142B with 3 SMU modules. Some Python in Jupyter Notebook created a nice programmable curve tracer. Unfortunately it's way too big to keep in my home lab at the moment..

Here's an example of results:
https://chart-studio.plotly.com/~msyrjala/13

[Anthocyanina]

Curve_Tracer_(ELEKTOR_12-89).pdf

Thank you! I have a question about the transformer used for the power supply. how do you get +14v and -14v from a 9v transformer? (they list a 9v transformer in the BOM) Thank you!

[tubularnut]

Thank you! I have a question about the transformer used for the power supply. how do you get +14v and -14v from a 9v transformer? (they list a 9v transformer in the BOM) Thank you!

The notes refer to 14V as the 'unloaded' voltage, which will drop under load.

The secondary voltage rating will be the RMS voltage.

For a half rectified voltage with capacitor, the peak 'unloaded' voltage be 1.414 x secondary voltage, so for 9 volts, this will be just short of 13V. Given that a transformer will often give out a higher than rated voltage, its possible to see 14V.

When under load it will drop to around 0.9 x secondary voltage.

The +14V and -14V is because there are 2 half wave rectifiers, one for +ve and one for -ve.

[Larryc001]

Another project for another day I’m afraid.

[Anthocyanina]

Thank you! I have a question about the transformer used for the power supply. how do you get +14v and -14v from a 9v transformer? (they list a 9v transformer in the BOM) Thank you!

The notes refer to 14V as the 'unloaded' voltage, which will drop under load.

The secondary voltage rating will be the RMS voltage.

For a half rectified voltage with capacitor, the peak 'unloaded' voltage be 1.414 x secondary voltage, so for 9 volts, this will be just short of 13V. Given that a transformer will often give out a higher than rated voltage, its possible to see 14V.

When under load it will drop to around 0.9 x secondary voltage.

The +14V and -14V is because there are 2 half wave rectifiers, one for +ve and one for -ve.

Oooh, that makes sense. I have a 12-0-12 transformer that i would like to use for this. should i then use +9v and -9v regulators? Sorry if this shouldn't be the place to ask these questions, thought to ask since it's related to a curve tracer project! Thank you!

[tubularnut]

Oooh, that makes sense. I have a 12-0-12 transformer that i would like to use for this. should i then use +9v and -9v regulators? Sorry if this shouldn't be the place to ask these questions, thought to ask since it's related to a curve tracer project! Thank you!

If you use one half of the 12v-0-12v(i.e 0-12v) I think you should be able to swap it directly in place of the 0-9v transformer. The documentation for the tracer refers regularly to use of the unregulated supply.

[khutch004]

A uTracer kit plus an old tube tester:

(picture will follow when I figure out how to do that!)

[Electro Fan]

A uTracer kit plus an old tube tester:

(picture will follow when I figure out how to do that!)

Thanks for posting.  That caused me to look up the uTracer.  The comments from the designer are pretty neat as he walks through his thinking on evolving the design to higher voltage.

https://www.dos4ever.com/uTracerlog6/tubetester6.html

[THDplusN_bad]

Good Day,

@Ground loop, I totally agree that the Heathkit IT-1121/3121 is a joy to work with. Both types are virtual identical, but have different colours and front panel knobs.

I have repaired my unit back in 2014, and modified it with BNC-output connectors for the outputs to the oscilloscope (to replace the 4mm/banana connectors), added a fuse holder for base step currents with a "fuse fail" indicator lamp and a custom scale.
I have also made a simple adapter with a ZIF-socket for the A/B testing of components, which has proven its value. Matching transistors is a joy with this. 
Photos attached.

I also enjoy using a Tektronix 5CT1N (basically the Tektronix 7CT1N's little brother for the Tektronix 51xx/54xx oscilloscopes). And the latest addition to my labs is an Agilent N3280A DC component tester. More of the latter soon...

Cheers,

THDplusN_bad

[jh15]

I have one (575) in top shape, what is the problem with yours?

In college, there was a brand new one, and I really liked the manual that was under that top compartment 0n the cabinet. Can't find one anywhere.

[THDplusN_bad]

@jh15: This might be well known to you, but electronic copies of all Tektronix manuals for the type 575 curve tracer can be found here: https://w140.com/tekwiki/wiki/575

Cheers,

THDplusN_bad

[jh15]

Thank you, I may have missed it. It is a small manual that fits in the pop-up storage area on the top of the right shell. I'll look again. Next best thing I liked were the pull-out quick guides on the bottom of most of my Sencore equipment.

[jh15]

Couldn't find the pop-up chamber manual. It must have a p/n, but I went down a rabbit hole of interesting things like info on my scope cart, etc.

[khutch004]

A uTracer kit plus an old tube tester:

(picture will follow when I figure out how to do that!)

Thanks for posting.  That caused me to look up the uTracer.  The comments from the designer are pretty neat as he walks through his thinking on evolving the design to higher voltage.

https://www.dos4ever.com/uTracerlog6/tubetester6.html

Yeah, he is one of us and he and his wife are a great team with occasional packing and shipping help from the kids, I think. The kit is very nicely done with a manual that does Heathkit one better. It was a great experience to work with them and build the kit. I don't need the new version, I don't know that I will be able to resist it!

[Electro Fan]

A uTracer kit plus an old tube tester:

(picture will follow when I figure out how to do that!)

Thanks for posting.  That caused me to look up the uTracer.  The comments from the designer are pretty neat as he walks through his thinking on evolving the design to higher voltage.

https://www.dos4ever.com/uTracerlog6/tubetester6.html

Yeah, he is one of us and he and his wife are a great team with occasional packing and shipping help from the kids, I think. The kit is very nicely done with a manual that does Heathkit one better. It was a great experience to work with them and build the kit.

Cool! 

I don't need the new version, I don't know that I will be able to resist it!

If you go for it, let us know.

[THDplusN_bad]

Good Day,

here are some details about the latest addition to my labs, an Agilent N3280A "component test DC source". Which I have turned into a curve tracer with some Python magic 

• There is surprisingly little information on this unit available on the internet. The official data sheet specs, user guide and an App Note on "Optimizing Power Product Usage to Speed Design Validation Testing" are available on the Keysight website https://www.keysight.com/us/en/product/N3280A/component-test-dc-source-5-w-4-outputs.html
  
• The unit basically provides four isolated, independent voltage/current sources, up to +/-10.25V and +/-512mA each. It sports four-wire outputs with current and voltage sensing and programming of both with 0.1% basic accuracy.
• It features four quadrant bipolar outputs, and it has exactly *one* front panel knob. Which is the POWER ON/OFF switch. 
  Which means that you have to program the device via GPIB to use it.
• The output connectors are a bit unusual, these fit 6 pole connectors, Würth Elektronik type 3673 male for custom cabling.
• I suspect these are the main reasons why this unit was offered at a relatively low price by a US-based surplus dealer. I have paid about as much for shipment and import duties as for the item itself...
• I have inspected the unit upon arrival, changed the line voltage to 230VAC and some basic cleaning of the housing was all it needed. I have replaced the noisy Pabst type 612 fan with a Noctua NF-A6x25 FLX 60 mm fan, which has slightly less air flow. This has reduced the noise emissions from a "screamin', I do not want this"-noise to a still noticeable, but completely acceptable level.
• The attached photos provide a few details, i.e. a XILINX Spartan XC2S50 as the digital brain, AD677 16-Bit 100 kSPS ADC from Analog Devices. The output power amplifiers are from APEX, type PA46.
  Most datecodes are from 1999. Note the massive toroid transformer.
• A closer inspection revealed that the input section of one power supply has been repaired in the past, apparently with original-spec'd components; but the solder joints do not like this was completed by Agilent/Keysight. 
  Anyway, all power supply units were found to be well within specs.
• I have also replaced the Schaffer line filter, which is another story on its own.
• The mounting screws for the GPIB-connector always need some moderate re-tightening. It pays back to use some quality 9/32 inch-/imperial tools for this.
• It is nice to see that the old HP plastic feet still fit this.

I have started to familiarize with the user guide, then to program the unit using Python and my NI USB GPIB-adapter about four weeks ago. I am quite pleased that the program creates some pretty nice plots such as the one included below.

That is more than 2,100 readings, from testing a standard BC547 NPN transistor. 

Cheers,

THDplusN_bad

[THDplusN_bad]

Added screenshot in PNG format

[Ground_Loop]

Good Day,

@Ground loop, I totally agree that the Heathkit IT-1121/3121 is a joy to work with. Both types are virtual identical, but have different colours and front panel knobs.

I have repaired my unit back in 2014, and modified it with BNC-output connectors for the outputs to the oscilloscope (to replace the 4mm/banana connectors), added a fuse holder for base step currents with a "fuse fail" indicator lamp and a custom scale.
I have also made a simple adapter with a ZIF-socket for the A/B testing of components, which has proven its value. Matching transistors is a joy with this. 
Photos attached.

I also enjoy using a Tektronix 5CT1N (basically the Tektronix 7CT1N's little brother for the Tektronix 51xx/54xx oscilloscopes). And the latest addition to my labs is an Agilent N3280A DC component tester. More of the latter soon...

Cheers,

THDplusN_bad

Nice mods. Got me thinking now.

[THDplusN_bad]

Curve tracing - or at least looking at those lovely curves --- it surely can turn into an obsession.

I have been using Python for programming an (inexpensive) USB-6008 DAQ box from National Instruments.

Guess what my hands grabbed for the creation of two input signals for testing two inputs...
An "Octopus" tester (a crude form of a component tester, well known, but still useful). That is not a curve tracer, but I just had to see a diode's I/V curve like in the attached screenshot... 
I cannot help it! 

Pls. ignore the voltage scaling; as it's irrelevant in this case.

Cheers,

THDplusN_bad

[Johnny10]

B&K Model 501A