What in the world is a 'hard copy' oscilloscope? - Page 1
Forum section: electronics / testgear

author: dizz
author_rank: Newbie
timestamp: December 16, 2016, 10:19:57 pm
content: 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-/232169748323Thanks in advance

author: Gyro
author_rank: Super Contributor
timestamp: December 16, 2016, 10:26:54 pm
content: I know rebadging is rife but that's ridiculous!(Sorry, couldn't resist)

author: madires
author_rank: Super Contributor
timestamp: December 16, 2016, 10:32:32 pm
content: Electrical isolation to prevent you from touching the case/ground. "Grid", "Heater" and "Cathode" should tell you why

author: Gyro
author_rank: Super Contributor
timestamp: December 16, 2016, 10:35:00 pm
content: Agreed, someserioushigh voltage isolation.

author: StillTrying
author_rank: Super Contributor
timestamp: December 16, 2016, 11:03:42 pm
content: Yep, that would be hard to copy.http://www.tek.com/manual-topic/printing-hard-copy-0

author: nctnico
author_rank: Super Contributor
timestamp: December 16, 2016, 11:18:21 pm
content: 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.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 16, 2016, 11:47:08 pm
content: It has a digitizer to allow printouts of waveforms - see this manual :http://exodus.poly.edu/~kurt/manuals/manuals/Tektronix/TEK%202252%20Operations.pdfLooks 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

author: tggzzz
author_rank: Super Contributor
timestamp: December 16, 2016, 11:49:21 pm
content: 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".

author: joeqsmith
author_rank: Super Contributor
timestamp: December 17, 2016, 01:24:06 am
content: I want to see whatever it was attached to.

author: SeanB
author_rank: Super Contributor
timestamp: December 17, 2016, 06:30:38 am
content: Probably the cathode of a large SEM, to monitor the current waveform as it scanned.

author: jonovid
author_rank: Super Contributor
timestamp: December 17, 2016, 06:38:23 am
content: hot glue gun sticks?

author: Monkeh
author_rank: Super Contributor
timestamp: December 17, 2016, 06:59:34 am
content: Quote from: jonovid on December 17, 2016, 06:38:23 amNylon or acetal rods.

author: ebclr
author_rank: Super Contributor
timestamp: December 17, 2016, 08:32:21 am
content: Sold for USD 64.14 it a very fair price

author: electrolust
author_rank: Unknown
timestamp: December 17, 2016, 10:36:14 am
content: 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.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 17, 2016, 10:54:33 am
content: Quote from: electrolust on December 17, 2016, 10:36:14 amAnd it can only print repetitive waveforms

author: nctnico
author_rank: Super Contributor
timestamp: December 17, 2016, 11:01:24 am
content: Quote from: electrolust on December 17, 2016, 10:36:14 amThese 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.

author: Luminax
author_rank: Regular Contributor
timestamp: December 17, 2016, 01:22:54 pm
content: What's those strange waveform on the display?

author: Fungus
author_rank: Super Contributor
timestamp: December 17, 2016, 03:16:14 pm
content: Quote from: nctnico on December 17, 2016, 11:01:24 amMaybe it had some sort of optical->paper printer in the empty space.

author: PointyOintment
author_rank: Frequent Contributor
timestamp: December 17, 2016, 03:19:54 pm
content: Quote from: Luminax on December 17, 2016, 01:22:54 pmI think that's actually text. Not sure what it says, though.

author: David Hess
author_rank: Super Contributor
timestamp: December 17, 2016, 05:02:39 pm
content: Quote from: mikeselectricstuff on December 16, 2016, 11:47:08 pmThis 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.