Analog XY Plotter Output to HPGL Translator

[@georgewerl6631]

Mr. Horstman: Excellent project. I actually replaced the X-Y board in my TEK 2232 with the GPIB board, now (almost) all of my instruments will plot directly to HPGL (I use a ProLogix GPIB to USB dongle to interface to the computer for capture). I have a couple of older instruments that I still cannot plot, one is an HP 3580a audio spectrum analyzer that outputs X, Y and contact closure for pen up/down. It looks like your project might be adaptable to this. It is not clear from the 3850a manual if the analyzer outputs the graticule or not, I might need to create that, also no on-screen data although I suppose I could write some interactive code to create that. Could be an interesting project for me to pursue, what do you think? Also, are bare shield boards available? George Werl

[@jshorstman1438]

Mr. Werl: Thanks! I did this project because it represents a great starting project for Arduino. It’s spec’d for the TEK2232: -2.5 to +2.5 input on X and Y translated to 0 to 5v for the Arduino ADC’s. Luckily, that’s a scale factor of 1.0 and a translation of +2.5v. Therefore, I could use precision unity-gain opamps (with built in precision laser matched feedback resistors). Unfortunately, it would be incompatible with the HP 3580A, except with substantial redesign. The HP 3580A manual states X-axis spread is 0 to 5v while Y-axis spread is -1.5 to 5.5v. X-axis could feed right through to Arduino but Y-axis would require a gain of 0.71 and a translation of +1.07v to produce 0-5v for Arduino. This non-unity gain would require external feedback resisters. It’s doable, and more of a challenge. You can use the schematic and software for this project as a ‘jumping off’ point for your project. I would be delighted to see your solution. Good luck!

[@jankoch]

Wasnt there an hpgl option in the scope making at least the conversion part obsolete?

[@jshorstman1438]

Yes. The Model 2232 was available with the GPIB option. However, this unit I bought at auction has only the X-Y Plotter option. So this was an opportunity for a hobby project using the Arduino UNO.

[@150551100]

Hi Mr Horstman,i just bought an old 2232 scope as well,i don't have an operation manual,i haven't figured out the storage feature,do you know if someone made a video on how to use this feature,or where to find an operation manual ? paper or pdf ?? Bye,Lucien

[@jshorstman1438]

Try this for a paper manual: www.manualslib.com/manual/2036603/Tektronix-2232.html#product-2232 There is a user manual and a service manual: Tektronix 2232 User Manual, 070-7066-02, 1993, 186pp Tektronix 2232 Service Manual, 070-7067-01, 1992, 366pp Here is a concise tutorial on Tektronix storage scope capabilities compared to the analog scope: 'Complete Analog Vs Digital Storage Oscilloscopes' kzbin.info/www/bejne/o3iWlqF9payshKM

[@andyk9685]

I was expecting the PD and PU command (pen down, pen up) but I did not see it .. Do you know why ? Cheers

[@jshorstman1438]

The lines were scrolling at approximately 614 lines per second. Out of the 153,733 lines that scrolled by only 147 were PD and 147 were PU commands. With the Windows screen updates and the frame rate of my video camera and only 32 viewable lines in the window there's no way the eye can catch the few PU/PD lines that fly by. To see for yourself, the whole output is in my GitHub page here: github.com/jshorstman/Analog-XY-Plotter-Output-to-HPGL-Translator/blob/master/Documentation/test200.plt?raw=true

[@Scrogan]

Aw man, I wish my scope had XY plotting output. Instead it outputs directly in HPGL, but not just XY values, it has a bunch of normal text, custom characters, and coordinate changes, as well as the grid lines and trace lines. I need to manually parse it and process certain elements to try and get an HPGL viewer to read it.

[@jshorstman1438]

I use SPLOT to open and display my HPGL files (€65, however, there is an evaluation version) www.swplot.com/splot.htm There may be other freeware HPGL viewers out there. Also, you may want to retrieve the HPGL and HPGL2 Reference guides: HPGL dokumen.tips/documents/chapter-9-hp-gl-graphics-language.html?page=7 HPGL/2 www.hpmuseum.net/document.php?catfile=213

[@squad_rcg.]

Can I use an amp other than AMP03?

[@jshorstman1438]

If you want a direct, drop in replacement it would need these specifications: *Bi-polar supply of at least ±6.3V. *Built-in voltage divider and feedback resistors (laser matched, preferably). *Same pin-out, of course. You’re free to redesign the circuit. Use any non-inverting, unity gain op-amp configuration. Ensure the op-amp, if single sided, can operate to the rails (0v). I recommend a resistor array for the voltage divider and feedback - they’re usually laser matched.