What in the world is a 'hard copy' oscilloscope?

[dizz]

This ebay listing here is calling this a 'hard copy'

What is the idea here?



http://www.ebay.com/itm/Tektronix-2252-100MHz-Prog-Hard-Copy-Oscilloscope-/232169748323

Thanks in advance

[Gyro]

I know rebadging is rife but that's ridiculous! 

(Sorry, couldn't resist)

[madires]

Electrical isolation to prevent you from touching the case/ground. "Grid", "Heater" and "Cathode" should tell you why

[Gyro]

Agreed, some serious high voltage isolation.

[StillTrying]

Yep, that would be hard to copy.
http://www.tek.com/manual-topic/printing-hard-copy-0

[nctnico]

This must be the ultimate floating scope!

BTW it says 'harcopy scope' on the badge and it seems to have a PC style printer port on the back. I have not seen this before so it may actually be a very rare model.

[mikeselectricstuff]

It has a digitizer to allow printouts of waveforms - see this manual :
http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/TEK%202252%20Operations.pdf

Looks like it used a low-speed ADC to digitise repetitive waveforms in sequential sampling mode, from :
http://w140.com/tekwiki/images/3/38/Tek_2252_2247A_2245A_Specs.pdf

[tggzzz]

When somebody falsely claims it is OK to "float a scope", you can say "it is safe in some circumstances; see this picture for what is necessary".

[joeqsmith]

I want to see whatever it was attached to.   

[SeanB]

Probably the cathode of a large SEM, to monitor the  current waveform as it scanned.

[jonovid]

  hot glue gun sticks? 

[Monkeh]

hot glue gun sticks?

Nylon or acetal rods.

[ebclr]

Sold for USD 64.14 it a very fair price

[electrolust]

I'm guessing the offset front is to place a camera?  Might be hard to work around the intended camera hence the extended controls.

But why a camera if it can print out a copy?  Maybe the printout doesn't have the reticle etc.

[mikeselectricstuff]

I'm guessing the offset front is to place a camera?  Might be hard to work around the intended camera hence the extended controls.

But why a camera if it can print out a copy?  Maybe the printout doesn't have the reticle etc.

And it can only print repetitive waveforms

[nctnico]

I'm guessing the offset front is to place a camera?  Might be hard to work around the intended camera hence the extended controls.

But why a camera if it can print out a copy?  Maybe the printout doesn't have the reticle etc.

These Tektronix scopes have grooves to hold a camera so I doubt they went through all the trouble just to take a picture of the screen.

[Luminax]

What's those strange waveform on the display?

[Fungus]

These Tektronix scopes have grooves to hold a camera so I doubt they went through all the trouble just to take a picture of the screen.

Maybe it had some sort of optical->paper printer in the empty space. 

[PointyOintment]

What's those strange waveform on the display?

I think that's actually text. Not sure what it says, though.

[David Hess]

It has a digitizer to allow printouts of waveforms - see this manual :
http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/TEK%202252%20Operations.pdf

Looks like it used a low-speed ADC to digitize repetitive waveforms in sequential sampling mode, from :
http://w140.com/tekwiki/images/3/38/Tek_2252_2247A_2245A_Specs.pdf

This is exactly it.  The 2252 uses sequential sampling to capture a repetitive waveform of 500 horizontal points or 50 points/div and 12-bit vertical resolution at full bandwidth which can then be transferred to a computer over GPIB or printed via a Centronics interface.  All 5 traces can be captured at once.

No other ability to manipulate or display captured waveforms is possible so it is literally an analog oscilloscope with digital hardcopy capability.  If the hardcopy capability is ignored, then it is a 2247A which is a great oscilloscope.

We got the story on these years ago over at TekScopes@yahoogroups.com.  Apparently Tektronix got curious and asked why they needed so many replacement front panels.  They were measuring high voltage tubes of some sort, maybe TWTs.