Author Topic: recent experience shopping for hobby scope in today's market. tek, rigol, ...  (Read 6155 times)

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Offline argile_tileTopic starter

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I went shopping for a used oscilloscope for hobby: you need it but don't want to give up parts money to have it :)  This turned out way difficult due to availability, terms of sale, disposable electronics.  I want to share some results.

all 4 are great

   .  waverate comes at a cost of price and inconvenience
      it is good for measurement, also bad for measurement, heavier, more likely to fail
   .  B&K Precision:  "Listed bandwidth is of little use if the scope can't trigger due to rise time."
   .  none below have channel isolation (expensive handhelds do, but limits certain measures)
      (you'll need to make custom (opamp) differentiator per situation need, unless your rich)
   ?  Is Tek just outdated and overpriced compared to Keysight and Rigol like Youtube says?

.  $ 600  Keysight EDUX1052A
   + certified in usa
   -  50 watts max
   -  fan always spins
   .  7 lb, 12.5 x 6.5 x 5.1  (most compact build of all 3)
   - 150 VRMS  (wall outlet)
   + better sales brochures (if your re-selling)
   -  7ns
   - 1Gs/s  per channel  (2G/s for both)
   +  100kpts ? 50?
   .  says web based panel - unk if browser mod needed, or use benchvue
   +  50k svrate - 10x fast
   +  > 100k wav/sec update
       (silgent 100k to 400k "depending on mode" (greedy spec given))
   -  upgradeable at factory ONLY - many features are "2G model only"
   +  UART (blah) and i2c
   +  2 FFT mode (magnitude phase), dual window
   .  unkown if it has color for waveform probability
   - acquisition 10ns,  + on averaging 1-64k
   ?  External trigger. (can be used as a 3rd digital channel at the front)
   .  3yr warrantee
   .  extended warrantee expensive, includes only 1 ESD incident
   ? no wifi dongle (but may not need it - may work off-the-shelf)
-------
   . online help (by pdf snapshot) looks plain text mostly, but well done
   - NO courseware, no way to put (manuals) on your oscope
   + has nice learning kit  (has courseware only for this)
   + free www help
   . https://github.com/Keysight
   -  no salesperson ready, phone chase - sales called 2 days later
   - 2G model is on backorder - you can't get one "today"
   + Keysight sells well, the 2G is on backorder, used keysight sell

.  $563  Tektronix TBS1000C
   + lower total cost and lower  dollars/year  on hobby
   + certified in usa
   .  30 watts max
   +  fanless design  (love changing fans in your PC?)
   + 4 lb, 19 x 7 x 4.25
   + 300 VRMS - both home (240) hvac and 3-phase (208) able
   + 2ns rise time (best in low budget class) (bandwidth ineffective if not trig'ed)
   + claims freq. accuracy
   + claims better triggering ability competitors, idk
   + 1Gs/s per channel
   -  20kpts (each channel)  (40?)
      how limiting idk:  20k is ALLOT for "one capture".  read about that before.
      if (tek, keysight, silgent) is limited by  kpt  for of (24hr capture of infrequent capture)
      is another matter entirely
   -  5k wavrate refresh can't catch as many glitches "visibly"
       (any rate is too slow to catch all glitches, however)
   -  NO i2c spi hackr stuffs (apparently SoC supports, but not software) (higher models have)
       has nice demo boards but not easy to FIND on web
   ?  tek claims  real-time sampling  others don't say.  is defined by tek as
       "records all samples at once, stores in 'memory', then repeats"
       (does that mean ADC is 20kpt?)  other brands say nothing about it
       tek oversampling supported also
   + dual window FFT , 2 FFT modes (dbV, RMS), dual window
   .  full 32 measurements shown where taken on curve
   + acquisition 4ns, - on ave of 2-256 (is ok, no 16 channel i2c either)
   +  5 yr warrantee
   +  Total Protection Plan  best ; $32/yr to stay protected from "some incidents"
       (comparable to apple care plan is $80/yr)
       $32/yr to insure you can sell (you have a scope) when upgrade time comes; worth it
       (doesn't say how many drops or ESD, leaves that in air)
   -  likely doesn't have color for waveform probability
   + tek's interface (has always) supports coarse/fine adjustment by nob
   + Wifi (w/usb dongle) "for courseware", seen only in tbs2000B ads (unk if off-the-shelf works)
-------
   + built-in help apparently (by snapshots in pdf) is graphical
       help can be individually enabled/disabled per topic - nice
   + courseware allows adding your own courses - so if you have info you
      like to have handy (say, forrest mims guides) ready on the scope w/o using PC
      100M of courseware can be stored on the scope.  scope also has built-in "introduction to osc"
   + has nice "demo boards", if you can find them on tek's site or google
      (they may not be for sale on website - may only come with special offers, idk)
   + free www help
   .  some free online resources - ie software AWG/win10
   .  https://github.com/tektronix
   ?  did not compare ecosphere (if ks has wider gambut of accessories / equip coverage)
   -  person on phone nice but  $80  shipping?  oh well
   + Tek sells well, even old Tek scopes find buyers

chinese scopes (mentioned quickly, not covered much) are good but "not as good".  being lower priced makes them well attractive:  but the trade-deficit factors say if your in usa they are "save a tiny bit now, cost you features and usa industry closures later"

.  $380  silgent sds1000X
   + certified in usa
   .  25W max  (would be a plus but ...)
   -  noisy fan problems, always running
   ?  has 84 color for waveform probability, but NOT ON by default ?  why ?
       has "menu transparency" again OFF by default
   +  > 100k wav/sec - 400k waverate "depending on mode"
       (questionable if this is better than ks or just a greedy spec)
   .  5.5 lb, 5.91 x 5.28 x 5.91  xxxx  17 x 15 x 10  (largest of all 3)
       photos show it is not box shaped:  the dimensions are WRONG
   -  3 yr warranty promised - but Amazon says "arrived broken on sale, refused to replace",
      "failed after year, failed after days" (rigol, silgen, f1nsr1, hantek, all really)
   -  "channel isolated spec", but docs warnings conflictingly say NOT ISOLATED, damaged
   -  20Mhz +- 40%  ... that's ALLOT of  %   "disclosed" what cond is 40% lost?  always?
   -  suspicious specs and warrantee
   --  help looks junky, screen text dump isn't even line formatted !!
   -  no courseware (in english distributions)
   -  despite linux arm ubu open claims is just as secretive as tek and ks
   .  has ubuntu suse "domination ware" support ONLY (other linux are excluded)
   .  www help is not much, however it's likely good in chinese
   .  forwardly has linux support:  ubuntu suse "domination ware" (other linux are excluded)
   .  ok user's manual (not all asian scopes have this)

?  Keysight DSOX1202G
?  $1,650  keysight "expensive" is upgradeable  (at what ransome, they are ruthless)
   + 200k wavrate/sec on DSOX model
   -  upgrade factory only  (not really optional)
   -  no used G models - on backorder
   +  uart, i2c, can, spi, ...  (these are on SoC, supported by software) + demo board
   +  sexier scope - but spec upgrades are really not allot for the money

.  $350  GW Instek GDS-1054B
   -  not certified in usa
   .  i like the way the hw "looks"
      .  boards laid out clean (easy to read) and "less crowded" than others
         pcb trace lines wide & easy to follow
      .  accessible to repair
      .  power supply is simple not complicated - repairable
   +  good fft
       -  no i2c
   .  ok user's manual (not all asian scopes have this)
   -  no courseware (in english distributions)
   ?  probably this is a great scope to have if in china or if ubucrat

. $329  Rigol DS1054Z
   -  not certified in usa
   + nice display / waverate - cost less than silgent
   + has i2c spi uart software built-in
   .  does not stand out in any particular way except that it is "as good choice" for asian brands
   .  ok user's manual (not all asian scopes have this)
   -  no courseware (in english distributions)

Summary:

.  comparison shows Tek has the best features for some buyers  despite being cheaper than Keysight and more expensive than chinese branded scopes.

.  I'm budget minded but don't want "un-certified" built things
.  I figure Tek costs me $75/year, all hobby money out the window, after sale in 5 yr.
   with warranty to insure i have a unit to sell (defintely cost less than 2 units)
.  I figure Keysight costs me $121/year, money out the window, after sale in 5 yr.
   (this isn't bad - but it depends how high on the shelf the hobby is)
.  I figure keysight sells for more, but Tek is a strong seller after all.

In[4]:= {(738+250+70),((738+250+70-450)/5),250/5}//N
Out[4]= {1058.,121.6,50.}
In[108]:= {(563+163+50),(563+163+50-400)/5,163/5}//N
Out[108]= {776.,75.2,32.6}

.  I could definitely use the savings.  My power source, AWG, part bin:  are all under-stocked  :)
   prices for good ones are enormous.
   (and that's before considering auto parts if the car dies)

A few more shopping isms...

I first looked for used.  All were so close to new price?  Why bother with the definite risk.  (many were even marked "no returns" despite being a poor price choice).  Two deals I found were "new opened" and "new in box" 15 yr old units.  Ok if your flying in the face of "no warranty" with disposable technology (look for keysight power supply replacement:  they are not for sale even for new units).  But check my cost formula.  When I go to sell I got a 20yr old unit and the buy has no clue whether it was new when I got it (a good deal if your never going to sell or willing to take the hit).
as for sales, the chinese scopes recently made do find buyers.  unsure about older models.  suspect (which models) they sell for less than Keysight or Tektronix when sold used.  (they cost less and sell lesser).

as for china "linux support" claims:  i am wary.  installing "a particular ubuntu" to make a proprietary binary run is a gamble, timely, boring:  ubu is "abandonment" (they kill software that WAS working), and hackers.  As for linux / arduino - keysight and tek support (i2c) also (not in tbs1000c but tbs2000c).  The chinese scopes don't support arduino (a product of china) except by "forum advertising name dropping".  And Pi would take a very expensive scope to analyze (a ridiculous proposition unless you own the company and profits are high this year).  I should say I'm not an "arduino hacker" and also don't believe low-end scopes i2c support would be good for debugging.  It would be "doing it the hard way".  It takes a full PC based software "to know much", which wouldn't be needed if wave forms looks good on a regular scope UNLESS it's a software issue: which is better resolved using software not a scope.

Tek and Keysight mention linux and also have github downloads - they are not completely anti-linux.
All of the above have "expensive much better models", none are from small companies.

One last good note for Tek and cost saving.  I watched EEVBlog and Signal Path (youtube) and noticed:  they don't use the good (on loan) scopes unless showcasing (advertising) or the measurement requires it.  They ususally uses the cheapest scope that is nice to work with.  Much safer.  This plays into the hobbyist need to "buy an expensive upgrade that is still miles behind 50Ghz".  It's probably not a good idea to spend "ones total hobby budget" on a scope that "just isn't ground breaking".
« Last Edit: February 23, 2023, 05:13:37 pm by argile_tile »
 

Online tautech

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Wow, just wow......never seen someone overthink a DSO purchase so.  :-//

Many here will advise to get a $500 Asian scope and be done with it as for most features they leave western DSO's in their wake.

A correction if I may:
Quote
$380 Siglent SDS1000X
Is discontinued.
2ch replacement SDS1202X-E
4ch replacement SDS1104X-E or 200 MHz model SDS1204X-E

Please don't purchase precision test equipment from Amazon when instead countrywide distributor networks exist and provide better support.
https://siglentna.com/how-to-buy/
Avid Rabid Hobbyist.
Some stuff seen @ Siglent HQ cannot be shared.
 
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Offline thm_w

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This is just all justification as to why you bought a Tek TBS1000. Which is fine, if you want to buy it go for it. But in terms of features per dollar its on the low end of whats out there.

https://www.eevblog.com/forum/testgear/tektronix-tbs1000c-released/

Also you claim Rigol is "-not certified in usa", which I doubt is true.
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Offline nctnico

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This is just all justification as to why you bought a Tek TBS1000. Which is fine, if you want to buy it go for it. But in terms of features per dollar its on the low end of whats out there.
Without knowing the OP's use case, there is absolutely no good advise to give.  :)
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline Zenith

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Without knowing the OP's use case, there is absolutely no good advise to give.  :)

Exactly. The sensible answer might be a Hameg 20MHz 203-4/5/6/7 solid state scope available on ebay for about 50 £/$/€ or less. No bragging rights, but a serviceable instrument within its limits.
 

Offline thm_w

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Without knowing the OP's use case, there is absolutely no good advise to give.  :)

Exactly. The sensible answer might be a Hameg 20MHz 203-4/5/6/7 solid state scope available on ebay for about 50 £/$/€ or less. No bragging rights, but a serviceable instrument within its limits.

Sure but they already spent $600 on the Tek, so they clearly have more than $50 to spare.
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Online bdunham7

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Without knowing the OP's use case, there is absolutely no good advise to give.  :)

It's fairly obvious what the OP's 'use case' is and I dare say he made quite reasonable choice.  It will be some time before (if ever) he realizes what 20K memory and 5K wfm mean or why they matter.  And in the meantime, he'll have a nice set of educational pop-up windows to refer to.

His post is mostly a massive mishmash of miscellanous misinformation though.  But there's no need for a blow-by-blow of that.
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 
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Offline Zenith

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It seems a bit like discussions about SLR cameras in the 60s/70s/80s with magazines dedicated to dissecting the differences between them.

As nctnico pointed out, without knowing the requirements of the o/p, it's no use giving exact advice.

It's the o/p's wad and if he gets satisfaction from blowing more than $600 on a scope that's up to him. Others may think it's sensible or not, as the case may be.
 

Offline argile_tileTopic starter

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Oh.  OP isn't going to argue anything.  The post is for fun.  Do you worst!
 

Offline 2N3055

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Oh.  OP isn't going to argue anything.  The post is for fun.  Do you worst!

So you posted to waste our time.
Thanks for clarifying..

Enjoy your new scope.
"Just hard work is not enough - it must be applied sensibly."
Dr. Richard W. Hamming
 
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Online J-R

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Can't believe the crying about having to read something.  I've seen it all...

OP: if you are truly in the US, then used is the way to go.  You'll get great deals and feel good about the money you saved. Ebay is a good place for this, but there are other places you can find used equipment and many ebay sellers have their own website where the same items are quite a bit cheaper.

I recently got a Keysight DSOX2004A and liberated it to an MSOX2024A+everything and it was only $700.  It seems like bragging, but it shows that the deals are out there.  There are a LOT of scopes that can be liberated, but doing that on a new scope is perhaps less than ideal.
 

Offline 2N3055

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Can't believe the crying about having to read something.  I've seen it all...

It is general attitude and not the only topic like that ... That is why I commented.

OP: if you are truly in the US, then used is the way to go.  You'll get great deals and feel good about the money you saved. Ebay is a good place for this, but there are other places you can find used equipment and many ebay sellers have their own website where the same items are quite a bit cheaper.

I recently got a Keysight DSOX2004A and liberated it to an MSOX2024A+everything and it was only $700.  It seems like bragging, but it shows that the deals are out there.  There are a LOT of scopes that can be liberated, but doing that on a new scope is perhaps less than ideal.

Good advice for people that have some patience and knowledge...
But it could be argued that for 700 USD MSOX2024A is not better scope than what you can get from Rigol or Siglent new for that kind of money..
As always, there is no single solution.
"Just hard work is not enough - it must be applied sensibly."
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Online BillyO

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I'm not saying the OP made a "wrong choice" but he certainly seemed to make it based on inaccurate information.  GI-GO  :-//

The scope of his choice is the sort of thing you'd find on the bench in a community college and it seems it's specifically made for that market.  Not much in the features department and only basic low spec  functionality.  If he is just starting out it might serve him well, but at quite a high cost for what he's getting.  His idea that Tek sells well might be true, but I don't think many will be lining up to buy that particular model.  There are plenty of 10-20 year old brand name scopes on the used market that will handily blow that unit away in performance for a lot less money.

A used 50MHz boat-anchor student model based on stale technology that has spent the last 5 years in the hands of a .. "learner" .. would quite honestly be the last thing on my shopping list.

But to each their own, I guess.   ::)
Bill  (Currently a Siglent fanboy)
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Offline rsjsouza

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In my opinion the OP made the non-optimal choice based on wrong and/or optimistic assumptions, sprinkled with lack of knowledge about modern oscilloscopes.

In my experience, any of the $400~500 mainstream models of the major Chinese brands (RigSigGwi) blows the chosen model out of the water. The Tek was up to date two decades earlier.
« Last Edit: February 26, 2023, 01:38:05 am by rsjsouza »
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Offline jasonRF

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It's fairly obvious what the OP's 'use case' is and I dare say he made quite reasonable choice.  It will be some time before (if ever) he realizes what 20K memory and 5K wfm mean or why they matter.  And in the meantime, he'll have a nice set of educational pop-up windows to refer to.


Agreed.  In fact, the lack of features may make it also easier to learn to use than a more full-featured scope.  Once they learn more, if they decide they want more features they can sell it and get something more capable. 

I am just a hobbyist and my nicer picoscope can support all of the analysis I will ever need, but I really hate fan noise so if I ever decided to get a bench scope I would probably want something like the Tek.  I would only consider used - the 1052B sometimes goes for $250ish or less on ebay.  Would rather do that than spend the same amount on a new fanless Owon.

jason




 

Offline David Hess

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.  $563  Tektronix TBS1000C
   -  20kpts (each channel)  (40?)
      how limiting idk:  20k is ALLOT for "one capture".  read about that before.
      if (tek, keysight, silgent) is limited by  kpt  for of (24hr capture of infrequent capture)
      is another matter entirely

The Tektronix TBS1000C supports delayed triggering so the 20k sample points can be moved to a later part of the waveform after the trigger.  This is the equivalent of delayed sweep in an older oscilloscope which effectively allows horizontal magnification of the waveform.

Quote
?  tek claims  real-time sampling  others don't say.  is defined by tek as
       "records all samples at once, stores in 'memory', then repeats"
       (does that mean ADC is 20kpt?)  other brands say nothing about it
       tek oversampling supported also

"Real time" in this case means that all channels sample at their maximum rate no matter how many channels are active.  Turning on more channels does not lower the sample rate of each channel.
 

Offline 2N3055

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.  $563  Tektronix TBS1000C
   -  20kpts (each channel)  (40?)
      how limiting idk:  20k is ALLOT for "one capture".  read about that before.
      if (tek, keysight, silgent) is limited by  kpt  for of (24hr capture of infrequent capture)
      is another matter entirely

The Tektronix TBS1000C supports delayed triggering so the 20k sample points can be moved to a later part of the waveform after the trigger.  This is the equivalent of delayed sweep in an older oscilloscope which effectively allows horizontal magnification of the waveform.

Quote
?  tek claims  real-time sampling  others don't say.  is defined by tek as
       "records all samples at once, stores in 'memory', then repeats"
       (does that mean ADC is 20kpt?)  other brands say nothing about it
       tek oversampling supported also

"Real time" in this case means that all channels sample at their maximum rate no matter how many channels are active.  Turning on more channels does not lower the sample rate of each channel.

Real time simply mean this is not repetitive sampling oscilloscope (i.e. it samples at real 2 GS/s rate, not equvalent rate).

And 20kpoint is very little or enough memory, depending on what you do. If you spend life using scope at short timebases looking at repetitive signals at higher frequencies it might be enough. Large memory helps with aliasing problems, it helps keep that sampling rate high while at longer timebase...
"Just hard work is not enough - it must be applied sensibly."
Dr. Richard W. Hamming
 

Offline nctnico

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For as long as a scope has peak detect mode, aliasing is not a problem at all. With short memory, you can't zoom in though to see if a small blib that pops up suddenly is something interesting or not.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline David Hess

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"Real time" in this case means that all channels sample at their maximum rate no matter how many channels are active.  Turning on more channels does not lower the sample rate of each channel.

Real time simply mean this is not repetitive sampling oscilloscope (i.e. it samples at real 2 GS/s rate, not equvalent rate).

Tektronix does not use "Real Time" to mean that at all.  Many of their previous "real time" DSOs also supported equivalent time sampling, including their earliest "real time' DSOs like the 2400 series.  It only means that sample rate (and record length) is independent of the number of channels.

Quote
And 20kpoint is very little or enough memory, depending on what you do. If you spend life using scope at short timebases looking at repetitive signals at higher frequencies it might be enough. Large memory helps with aliasing problems, it helps keep that sampling rate high while at longer timebase...

My point is that the delayed triggering capability makes up for the short record length in most cases, and it has nothing to do with repetitive signals; it works fine in single sweep acquisition mode.  The TBS1000C can view portions of a waveform at high sample rates at any point after the trigger, where DSOs without this feature are limited by their record length.
 

Offline zrq

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Quote
And 20kpoint is very little or enough memory, depending on what you do. If you spend life using scope at short timebases looking at repetitive signals at higher frequencies it might be enough. Large memory helps with aliasing problems, it helps keep that sampling rate high while at longer timebase...

My point is that the delayed triggering capability makes up for the short record length in most cases, and it has nothing to do with repetitive signals; it works fine in single sweep acquisition mode.  The TBS1000C can view portions of a waveform at high sample rates at any point after the trigger, where DSOs without this feature are limited by their record length.

You are right if the interesting short time feature is appearing repetitively at a predictable interval after some triggerable event. Which is arguably not so common.
 

Offline David Hess

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My point is that the delayed triggering capability makes up for the short record length in most cases, and it has nothing to do with repetitive signals; it works fine in single sweep acquisition mode.  The TBS1000C can view portions of a waveform at high sample rates at any point after the trigger, where DSOs without this feature are limited by their record length.

You are right if the interesting short time feature is appearing repetitively at a predictable interval after some triggerable event. Which is arguably not so common.

The more useful feature, which all of the DSOs under discussion lack, is trigger after delay, which is what you get with a dual delayed timebase with two sweeps and two triggers.

After the first trigger, there is an adjustable delay, and then a second trigger produces the acquisition.  For instance when probing a switching power supply, this allows locking onto the reverse recovery waveform even in the presence of jitter.

In the past this was used to trigger at the start of a video frame, and then select a horizontal line to display with no jitter.  No amount of record length can correctly display that in real time; it requires the second trigger.

 

Online bdunham7

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The more useful feature, which all of the DSOs under discussion lack, is trigger after delay, which is what you get with a dual delayed timebase with two sweeps and two triggers.

After the first trigger, there is an adjustable delay, and then a second trigger produces the acquisition.  For instance when probing a switching power supply, this allows locking onto the reverse recovery waveform even in the presence of jitter.

If you wanted an entry-level scope with retro features, the elderly but still produced Siglent SDS1102CML actually is sort of interesting.  It doesn't have an explicit B-sweep or B-trigger, but it does have trigger delay and I think you could manage something close using the alternate trigger, some holdoff and the rather odd dual-timebase feature where each channel can have independent horizontal settings.  You would have to feed the signal into both channels, which is somewhat of a gnarly probing issue, and I haven't tried it so I'm just speculating.  Other retro features include the 50GSa/s ETS and video triggering.

You're right that trigger delay is limited by record length, but that can be many thousands of divisions depending on your scope and setup.
A 3.5 digit 4.5 digit 5 digit 5.5 digit 6.5 digit 7.5 digit DMM is good enough for most people.
 

Offline 2N3055

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My point is that the delayed triggering capability makes up for the short record length in most cases, and it has nothing to do with repetitive signals; it works fine in single sweep acquisition mode.  The TBS1000C can view portions of a waveform at high sample rates at any point after the trigger, where DSOs without this feature are limited by their record length.

You are right if the interesting short time feature is appearing repetitively at a predictable interval after some triggerable event. Which is arguably not so common.

The more useful feature, which all of the DSOs under discussion lack, is trigger after delay, which is what you get with a dual delayed timebase with two sweeps and two triggers.

After the first trigger, there is an adjustable delay, and then a second trigger produces the acquisition.  For instance when probing a switching power supply, this allows locking onto the reverse recovery waveform even in the presence of jitter.

In the past this was used to trigger at the start of a video frame, and then select a horizontal line to display with no jitter.  No amount of record length can correctly display that in real time; it requires the second trigger.

Of course even the cheap digital scopes have that functionality. On SDS1000X-E it is called interval trigger.

You have one trigger satisfied, then time limit and then when second trigger comes in, you capture the buffer.

On cheap DS1000Z you have similar Delay trigger and  N-th edge trigger, where you can choose both time delay and number of edges.

On more expensive scopes more sophisticated version is  called Qualified trigger, where you can actually mix and match trigger types.

For video you have video triggers.
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Offline David Hess

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The more useful feature, which all of the DSOs under discussion lack, is trigger after delay, which is what you get with a dual delayed timebase with two sweeps and two triggers.

After the first trigger, there is an adjustable delay, and then a second trigger produces the acquisition.  For instance when probing a switching power supply, this allows locking onto the reverse recovery waveform even in the presence of jitter.

In the past this was used to trigger at the start of a video frame, and then select a horizontal line to display with no jitter.  No amount of record length can correctly display that in real time; it requires the second trigger.

Of course even the cheap digital scopes have that functionality. On SDS1000X-E it is called interval trigger.

You have one trigger satisfied, then time limit and then when second trigger comes in, you capture the buffer.

Usually they have something, but it is not as flexible, and in Rigol's case they outright lied in their documentation deliberately confusing their delayed trigger, which was not even that, with what older oscilloscopes provided with a delayed sweep.

Quote
For video you have video triggers.

Old oscilloscopes with video triggering still worked as I described, so their video trigger is not like a modern scope but instead only extracted the video trigger from the video waveform.  Modern instruments with video triggers allow the video line to be selected, although that feature goes back to at least the 1980s so it has been around for a while.  Before that some oscilloscopes provided countdown trigger capability, but I doubt it was ever used for video, although it could have been.
 

Offline zrq

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I don't want to derail this thread further. I don't really understand, which feature is available on the TBS1000C but not SDS1000X-E ?

Maybe more security of firmware is one example of such a feature, (AFG31000 seems to be based on the same platform, and I'm not sure if it's Secure Boot or some softer checks that maybe bypassed by, for example open case and use JTAG) https://www.eevblog.com/forum/testgear/tektronix-afg-31000-hack/msg3211768/#msg3211768 .
 


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