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Saving Curves onto a 1520

Joined
May 5, 2022
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A bit off topic but anyone where to find DOS Oscilloscope Software that would work on a 286 1520? I have looked a bit but so far, no luck.
If anyone is curious that is a tube trace of a 3AU6 tube on a Tek 577D1 which doesn't have a serial port (it's from 1972), but I am hoping to save waveforms/analyze off of my 222a or TDS 420a (not pictured) using my 1520.
Thanks!
 

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Well the 222A has some sort of a "comm port" but to me that's really odd because almost every scope I know of was using GPIB to communicate between devices. Can't really help you there.
The 577D1 has that, but the GRiD 1520 isn't like the Compass and doesn't have GPIB onboard.
I know there was a time many many years ago where "mini scopes" were advertised in the back of magazines that plugged into the serial or parallel port and supported DOS but I have never actually seen one in reality.
 
Well the 222A has some sort of a "comm port" but to me that's really odd because almost every scope I know of was using GPIB to communicate between devices. Can't really help you there.
The 577D1 has that, but the GRiD 1520 isn't like the Compass and doesn't have GPIB onboard.
I know there was a time many many years ago where "mini scopes" were advertised in the back of magazines that plugged into the serial or parallel port and supported DOS but I have never actually seen one in reality.
Thanks, but as I mentioned earlier my 577D1 doesn’t have a serial or gpib out and I would need a add on mod (they do exist for usb at least) for the traces to be saved. For the 222 it looks like I would need some software that I have been unsuccessful in finding the analysis software (like CAT200) thus far.
I did find the basic terminal program however (https://www.tek.com/en/support/software/utility/222-power-scout-utility-software)
 

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Sorry, I meant the TDS 420a has GPIB.
NP, I was able to get that terminal software running on my 1520 and printed out some sample waveforms. However, I ordered a breakout box because the rs232 requires a specific pinout in the 222a for actual communication with the scope.
I would be very happy to be able to non-destructively add a mod to my 577d1 that allows a similar capture, but it would be significantly harder because it's an analog instrument (would require digitizing...)
 
Given the vintage of this thing, it's pretty clear that there aren't any external outputs. It seems that your best option is what we used to do back in the day on our 7000 series scopes--a Polaroid 'scope camera. Since they're not really used any more, such cameras are very cheap on the used market.

At least one fellow has worked up a digicam attachment for his old scope: https://hackaday.io/project/171961-a-digital-camera-for-analog-oscilloscopes
 
Given the vintage of this thing, it's pretty clear that there aren't any external outputs. It seems that your best option is what we used to do back in the day on our 7000 series scopes--a Polaroid 'scope camera. Since they're not really used any more, such cameras are very cheap on the used market.

At least one fellow has worked up a digicam attachment for his old scope: https://hackaday.io/project/171961-a-digital-camera-for-analog-oscilloscopes
Cool! I will check it out
These guys on eBay also sell a USB attachment mod but it's too expensive for me to consider (960$!)
 
The price on that one is now 1 cent short of USD$4000.00!
Probably just a MCU with a couple of DACs. But hey, given the small market, maybe it's worth it.
 
The price on that one is now 1 cent short of USD$4000.00!
Probably just a MCU with a couple of DACs. But hey, given the small market, maybe it's worth it.
To be fair that includes the curve tracer as well but yes.
Below it says they will sell the usb device separately for 960$.
Based upon where it hooks up it seems as though it just draws off of the CRT control grid for digitization.
 
I was able to get the 222a to communicate with the 1520 using that software.
For anyone interested, here is the step generator output for a 577d1.
IMG_1339.jpeg
 

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I was able to get the 222a to communicate with the 1520 using that software.
For anyone interested, here is the step generator output for a 577d1.
View attachment 1247885
At first, I would have said this was impossible. But, I see the trace on the screen of the Grid.
But I do have a question: the sawtooth wave on the screen of the Grid doesn't look like the trace seen on the 222.
Are we looking at the same waveforms?
Thanks,
-Shawn
 
At first, I would have said this was impossible. But, I see the trace on the screen of the Grid.
But I do have a question: the sawtooth wave on the screen of the Grid doesn't look like the trace seen on the 222.
Are we looking at the same waveforms?
Thanks,
-Shawn
No, the waveform is the previous one shown when the step generator is set at 1X on the 577 as shown in the video clip. When set at a higher speed you can see the individual steps as shown on the saved Grid trace.
It wasn't actually that difficult as Tektronix had software (posted above) that lets me control the 222a from the command line on the 1520 and can acquire the digitized waveform from it through the serial port. The 222a is doing the digitizing of the analog output of the 577d1 and I can save and print waveforms with the 1520 from the 222a.
My next step is finding out how I can connect to my 7D20 https://w140.com/tekwiki/wiki/7D20 (Need a GPIB converter box)
Or eventually my R7912 which uses a proprietary interface for a PDP-11 :)
Check out the memory on this guy R7912(1973!!):
IMG_1928.jpeg
 
I was also thinking this might work to convert gpib to parallel for the 1520...
If anyone has experience with this, I would appreciate it!
I have a GPIB interface for the Grid. It slides in to the battery port.
 
You'll have to rotate the 2nd one. I'll admit, opening the box was like opening Marcellus' briefcase in Pulp Fiction! :biggrin:A little mystical. :)
No, the waveform is the previous one shown when the step generator is set at 1X on the 577 as shown in the video clip. When set at a higher speed you can see the individual steps as shown on the saved Grid trace.
It wasn't actually that difficult as Tektronix had software (posted above) that lets me control the 222a from the command line on the 1520 and can acquire the digitized waveform from it through the serial port. The 222a is doing the digitizing of the analog output of the 577d1 and I can save and print waveforms with the 1520 from the 222a.
My next step is finding out how I can connect to my 7D20 https://w140.com/tekwiki/wiki/7D20 (Need a GPIB converter box)
Or eventually my R7912 which uses a proprietary interface for a PDP-11 :)
Check out the memory on this guy R7912(1973

I have never seen one in the wild.
Could you post pics? Maybe it's possible to create one from off the shelf parts... :unsure:
 

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Thats pretty cool! I wonder if that would allow me to communicate with my 7D20!
The R7912 will take some more work as it is for a different interface and although I fixed its power supply it uses a proprietary digital interface, and the composite video card isn't outputting anything...
If you are ever willing to let it go let me know and I would be happy to buy it from you and put it to work!
 
Just an update for anyone interested, I was able to get some basic communication using the Grid GPIB device from Shawnerz (thanks again) to a Tektronix 7D20 https://w140.com/tekwiki/wiki/7D20
(Much more powerful than a 222a) running in a 7623A!
I will be working on actually running some useful software to actually visualize and print the waveforms rather than just a data dump text printout of a flat line (shown here)
Refresh of image is interfering with the camera shot...



IMG_2179.jpeg
 
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