Author Topic: Are old digital scopes worth the money?  (Read 19521 times)

0 Members and 1 Guest are viewing this topic.

Offline Wuerstchenhund

  • Super Contributor
  • ***
  • Posts: 3079
  • Country: gb
  • Able to drop by occasionally only
Re: Are old digital scopes worth the money?
« Reply #25 on: March 29, 2016, 08:17:45 am »
When HP did ship a minicomputer too early, Packard sent a two line memo to the manager requesting that HP not ship products until they met their specification. The manager framed the memo, and everybody in HP was told the story for 10-20 years thereafter.
And now they are out of this business.

Yes, like pretty much everyone else because minicomputers are no longer a thing :palm:

HP is still in desktops, workstations and servers from 'pretty small' to 'very large'

Quote
Cool story, but I'd rather use slightly buggy hardware delivered in timely manner, than perfect thing delivered 2 years tool late and 10x more expensive.

HP wasn't (and still isn't) a Chinese B-brand who doesn't get software, so it most certainly did not take them anything close to that. In reality, the time to fix that was probably more like days and weeks.
 

Online coppice

  • Super Contributor
  • ***
  • Posts: 6461
  • Country: gb
Re: Are old digital scopes worth the money?
« Reply #26 on: March 29, 2016, 08:27:37 am »
Yes, eBay is an expensive place to buy test gear.
Caveat: I've never bought general purpose test equipment, like a scope, on E-Bay. I have bought specialist test equipment there.

I wouldn't say E-Bay is expensive. I would say erratic. If a flood of similar stuff passes through, prices plummet. If people feel their is more demand than supply they can rise quickly. Unless you are in a hurry, bide your time and follow what's going on.
 

Offline pxl

  • Regular Contributor
  • *
  • Posts: 126
  • Country: hu
Re: Are old digital scopes worth the money?
« Reply #27 on: March 29, 2016, 08:48:55 am »
On those time bases, where large mem really kicks in, eg at 500us, which is your preferred memory settings? You may find large mem useful sometimes on every time bases, that is out of question, but what are you using usually?

Most (all?) DSOs have an "auto" setting for memory size. In auto mode they choose a memory size that gives a good update rate for the selected time base.

Most of the time you can just leave it in auto mode and it will be good.

So most of the time the large memory does not matter at all, because the scope will use small memory. Most of the time.
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 12373
  • Country: 00
Re: Are old digital scopes worth the money?
« Reply #28 on: March 29, 2016, 08:58:20 am »
Most (all?) DSOs have an "auto" setting for memory size. In auto mode they choose a memory size that gives a good update rate for the selected time base.

Most of the time you can just leave it in auto mode and it will be good.

So most of the time the large memory does not matter at all, because the scope will use small memory. Most of the time.

It matters when you're capturing, zooming and scrolling.

(which is an important feature of DSOs)

 

Online tggzzz

  • Super Contributor
  • ***
  • Posts: 13848
  • Country: gb
    • Having fun doing more, with less
Re: Are old digital scopes worth the money?
« Reply #29 on: March 29, 2016, 08:59:29 am »
When HP did ship a minicomputer too early, Packard sent a two line memo to the manager requesting that HP not ship products until they met their specification. The manager framed the memo, and everybody in HP was told the story for 10-20 years thereafter.
And now they are out of this business.

Yes, like pretty much everyone else because minicomputers are no longer a thing :palm:

HP is still in desktops, workstations and servers from 'pretty small' to 'very large'

Quote
Cool story, but I'd rather use slightly buggy hardware delivered in timely manner, than perfect thing delivered 2 years tool late and 10x more expensive.

HP wasn't (and still isn't) a Chinese B-brand who doesn't get software, so it most certainly did not take them anything close to that. In reality, the time to fix that was probably more like days and weeks.

I can't instantly find a decent reference, but from (faulty?) memory the delay was 6 months to a year. The primary motivation for accepting the delay was that back then HP thought that a reputation for bulletproof dependability and corporate responsibility were key business assets. A corollary is that other companies' products often had marginally better specifications, but engineers trusted HP to "do the right thing" and "do the thing right".
« Last Edit: March 29, 2016, 09:02:39 am by tggzzz »
There are lies, damned lies, statistics - and ADC/DAC specs.
Glider pilot's aphorism: "there is no substitute for span". Retort: "There is a substitute: skill+imagination. But you can buy span".
Having fun doing more, with less
 

Offline Wuerstchenhund

  • Super Contributor
  • ***
  • Posts: 3079
  • Country: gb
  • Able to drop by occasionally only
Re: Are old digital scopes worth the money?
« Reply #30 on: March 29, 2016, 09:03:35 am »
'Lot of bandwitdh' and 'small amount of money' are mutually exclusive if you're buying online.
Yes, for new kit. For 2nd hand gear it's not. In fact, "lots of bandwidth" can often be had for similar prices as "modest bandwidth".
I'm not sure if that equates to "small amount of money" or not. Modest bandwidth can be expensive, too.  :P

True. I guess it depends on how a "small amount of money" is defined. Even on the 2nd hand market there's a certain limit below which you're pretty much just getting crap. I'd put this limit to somewhere between $250 and $300. For scopes, you're unlikely to find anything useful below that.
 

Online nctnico

  • Super Contributor
  • ***
  • Posts: 21292
  • Country: nl
    • NCT Developments
Re: Are old digital scopes worth the money?
« Reply #31 on: March 29, 2016, 10:30:35 am »
IMHO an older digital scope is only worth the money if you need a lot of bandwitdh for a small amount of money.
'Lot of bandwitdh' and 'small amount of money' are mutually exclusive if you're buying online.
I paid $225 for a working 4 channel 500MHz Tektronix TDS510A from Ebay 6 or 7 years ago. Even including shipping it was a bargain.
Could you go out today and get another one like that...?
Ofcourse! Lots of Tektronix scopes from these series on Ebay and if not today then some patience will get you one quickly.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline pxl

  • Regular Contributor
  • *
  • Posts: 126
  • Country: hu
Re: Are old digital scopes worth the money?
« Reply #32 on: March 29, 2016, 10:41:31 am »
Most (all?) DSOs have an "auto" setting for memory size. In auto mode they choose a memory size that gives a good update rate for the selected time base.

Most of the time you can just leave it in auto mode and it will be good.

So most of the time the large memory does not matter at all, because the scope will use small memory. Most of the time.

It matters when you're capturing, zooming and scrolling.

(which is an important feature of DSOs)

24k memory means approx 5 timebase steps when zooming. 12Mbyte means about 14 steps (1Mbyte means 10 steps). The question is (if I get the point), whether that 5 steps zooms is enough usually or need to go for that 14 steps zoom.
 

Offline pxl

  • Regular Contributor
  • *
  • Posts: 126
  • Country: hu
Re: Are old digital scopes worth the money?
« Reply #33 on: March 29, 2016, 10:44:30 am »
Btw, for rigol dso1000z, what is the default memory setting in auto mode for 500us?
 

Online Kjelt

  • Super Contributor
  • ***
  • Posts: 6091
  • Country: nl
Re: Are old digital scopes worth the money?
« Reply #34 on: March 29, 2016, 10:58:40 am »
Small advice: just do your homework before buying, whats inside the machine what does it run?
For instance I would never touch the old Lecroy scopes before they used standard pc boards with windows OS. Because they had some proprietary Lecroy OS on it.
If the hdd fails where do you get it from? Perhaps you can clone the old one before it breaks, than you need a small hdd (newer ones are not running) to clone it etc. etc.
So you should ask yourself the question can I fix it if something breaks.
I had a colleague that had some very expensive Tektronix scope that had 3 motherboards on it, and it took him 2 years and a lot of help from other owners to clone some content like cal settings etc. to get it going again.
For hobbie it can be a challenge but if you really want/need it as a main measurement instrument I would think twice.
 

Offline pxl

  • Regular Contributor
  • *
  • Posts: 126
  • Country: hu
Re: Are old digital scopes worth the money?
« Reply #35 on: March 29, 2016, 11:11:37 am »
Btw, for rigol dso1000z, what is the default memory setting in auto mode for 500us?

another question, if you stop/zoom the acq. will it use more memory?
 

Online nctnico

  • Super Contributor
  • ***
  • Posts: 21292
  • Country: nl
    • NCT Developments
Re: Are old digital scopes worth the money?
« Reply #36 on: March 29, 2016, 11:16:10 am »
Btw, for rigol dso1000z, what is the default memory setting in auto mode for 500us?
another question, if you stop/zoom the acq. will it use more memory?
No because the samples aren't there. The best thing is when an oscilloscope always uses all the memory so you can zoom in after capturing a signal.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline grouchobyte

  • Regular Contributor
  • *
  • Posts: 240
  • Country: ca
Re: Are old digital scopes worth the money?
« Reply #37 on: March 29, 2016, 11:36:49 am »
There is absolutely no reason in the world to obtain an "older digital scope" when you can get a modern up to date Rigol, Sigilent, Owon, Instek, Tek, Keysight, LeCroy, Hameg, etc for pretty cheap with more bells and whistles, faster waveforms per sec, more waveform memory and software functionality. Used or new, its a no brainer

Think of it this way.......it you had a choice, would you buy a Zune MP3 player or have just play your music on an iphone or android device?

The nostalgia you have for the world of old digital scopes is a graveyard of relics you wouldn't want. Sure, some can argue that they used a pretty shmick box back in the day, but that was BACK IN THE DAY.
Move on.

@grouchobyte;
 

Offline Wuerstchenhund

  • Super Contributor
  • ***
  • Posts: 3079
  • Country: gb
  • Able to drop by occasionally only
Re: Are old digital scopes worth the money?
« Reply #38 on: March 29, 2016, 11:37:06 am »
Small advice: just do your homework before buying, whats inside the machine what does it run?
For instance I would never touch the old Lecroy scopes before they used standard pc boards with windows OS. Because they had some proprietary Lecroy OS on it.
If the hdd fails where do you get it from? Perhaps you can clone the old one before it breaks, than you need a small hdd (newer ones are not running) to clone it etc. etc.

 :wtf:

Small advice from someone who actually knows these scopes: do your homework and get a basic clue before sprouting nonsense.  :palm:

Almost all older LeCroy scopes (i.e. non-Windows scopes), which includes all the ones mentioned in this thread, have their OS in flash ROM. And yes, the flash images are still available. An optional hard drive (actually a IBM MicroDrive, a small PCMCIA hard disk that plugs into the external PCMCIA slot in the scope) was available as option to store screenshots and data on it, but this can easily be replaced by a standard CF card.

The only exception was the (somewhat rare) ScopeStation 140 which is based on the old LW410/420 AWG and which uses a hard disk running Microsoft DOS. There are ways to replace that hard disk with a small CF card, and the restore floppies necessary to restore the disk content are generally available through the LeCroy Yahoo group (if you ask there you'll get them). But I wouldn't recommend buying a ScopeStation, simply because unlike for other LeCroy scopes there are no service manuals out there.

Quote
I had a colleague that had some very expensive Tektronix scope that had 3 motherboards on it, and it took him 2 years and a lot of help from other owners to clone some content like cal settings etc. to get it going again.

If he was similarly clueless then this isn't a surprise. And I bet this was a Windows scope.
« Last Edit: March 29, 2016, 12:16:11 pm by Wuerstchenhund »
 

Offline Wuerstchenhund

  • Super Contributor
  • ***
  • Posts: 3079
  • Country: gb
  • Able to drop by occasionally only
Re: Are old digital scopes worth the money?
« Reply #39 on: March 29, 2016, 12:04:17 pm »
There is absolutely no reason in the world to obtain an "older digital scope" when you can get a modern up to date Rigol, Sigilent, Owon, Instek, Tek, Keysight, LeCroy, Hameg, etc for pretty cheap with more bells and whistles, faster waveforms per sec, more waveform memory and software functionality. Used or new, its a no brainer

Really? What new Hameg, Keysight or LeCroy scope do you get for $300? Or as a matter, what used ones that aren't 20 years old, aren't analog scopes and aren't shit (i.e. LeCroy WaveAce)?

I'm not saying that you can't get great scopes for good prices but newer scopes with decent specs from the big brands cost still a bit more than the $300 the scopes that have been discussed here.

As stated before, I decided against a new Rigol when I read about their idiotic hardware design. The 54645D I bought might be old but at least HP knew how to build an oscillator.

Siglent is a no-go as they are utterly incompetent in writing firmware. I had a SDS2000 scope (their most expensive scope) and the firmware was still unusable 2 years after the scope has been released, and it seems this saga is still ongoing. Siglent also recently released a new series of spectrum analyzers (SSA3000X), and again it comes with retarded bugs (like having the window for selecting the place and file name of a screenshot in the actual screenshot :palm: ). If your time is worthless enough to play beta testers for a bunch of clown then more power to you, I won't touch their gear with a bargepole.

OWON, well the scopes look and feel like toys, and while it seems they have less firmware issues than Rigol and Siglent their hardware quality seems to be poor.

Quote
Think of it this way.......it you had a choice, would you buy a Zune MP3 player or have just play your music on an iphone or android device?

What a terrible comparison. Seriously, how is the question if buying an older or newer scope even related to playing music on a separate music player vs a multi-function device like a cell phone? Does your cell phone play the MP3 file somehow better than the Zune? What's the point?

Quote
The nostalgia you have for the world of old digital scopes is a graveyard of relics you wouldn't want. Sure, some can argue that they used a pretty shmick box back in the day, but that was BACK IN THE DAY.
Move on.

It has nothing to do with nostalgia but simply what you can get for little money. Which pretty much buys you new bottom-of-the-barrel B-brand or old big brand kit. It also leaves other things aside, for example the simple fact that some of these 20 year old scopes like the LeCroy 9300 Series in terms of functionality and capability still wipe the floor with everything that has been made by the B-brands, including Rigol's $9k+ DS6000.

Go figure.
« Last Edit: March 29, 2016, 12:07:13 pm by Wuerstchenhund »
 

Offline vk6zgo

  • Super Contributor
  • ***
  • Posts: 6046
  • Country: au
Re: Are old digital scopes worth the money?
« Reply #40 on: March 29, 2016, 12:16:49 pm »
Are old digital scopes like those lecroy or hp 100 mhz 200msa/s monochrome worth the money? ive seen them on ebay and other places sometimes quite expensive

There's nothing wrong with the scopes if you can get them at a bargain price. OTOH they're old.

Yes, eBay is an expensive place to buy test gear.

would you pick one of those or a good analog scope?

I'd pick even a medium/low DSO over an old analog scope. They do stuff the old analog scopes don't do.

The only reason for buying analog is if it has a huge bandwidth which you really need and you got it at an amazing price.

Or,if you want to look at any signal with high frequency components using a fairly long time/div setting.
This is not an unusual requirement --hum on a pulse train is one,looking for hum & clamping errors on an analog TV signal at frame rate is another.
Early DSOs descend into a nightmare of aliasing!
Quote
If not? Nope. Why would you want something that takes up your entire bench and does half the things a DSO can do?
Many early DSOs are larger than the same generation analogs.

If I could pick up,say, a TDS220 for around $A100,I'd buy it,just for fun,but they sell for crazy prices on eBay.
 

Offline pxl

  • Regular Contributor
  • *
  • Posts: 126
  • Country: hu
Re: Are old digital scopes worth the money?
« Reply #41 on: March 29, 2016, 12:17:38 pm »
Btw, for rigol dso1000z, what is the default memory setting in auto mode for 500us?
another question, if you stop/zoom the acq. will it use more memory?
No because the samples aren't there. The best thing is when an oscilloscope always uses all the memory so you can zoom in after capturing a signal.

I started to be confused now. In this case if we would like to use the advantages of large memory, then we
- use the scope in auto mem (because otherwise it would be slow)
- if we would like to zoom then we need to switch to large mem mode
- zoom and analyze
- switch back to auto mode for normal workflow
- if we would like to zoom again then goto 10

Probably I misunderstood something.
 

Online nctnico

  • Super Contributor
  • ***
  • Posts: 21292
  • Country: nl
    • NCT Developments
Re: Are old digital scopes worth the money?
« Reply #42 on: March 29, 2016, 12:29:43 pm »
Btw, for rigol dso1000z, what is the default memory setting in auto mode for 500us?
another question, if you stop/zoom the acq. will it use more memory?
No because the samples aren't there. The best thing is when an oscilloscope always uses all the memory so you can zoom in after capturing a signal.

I started to be confused now. In this case if we would like to use the advantages of large memory, then we
- use the scope in auto mem (because otherwise it would be slow)
- if we would like to zoom then we need to switch to large mem mode
- zoom and analyze
- switch back to auto mode for normal workflow
- if we would like to zoom again then goto 10

Probably I misunderstood something.
You didn't misunderstood. It is the price you pay for getting an inexpensive scope which does not have dedicated hardware for dealing with waveform display.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 12373
  • Country: 00
Re: Are old digital scopes worth the money?
« Reply #43 on: March 29, 2016, 01:52:09 pm »
24k memory means approx 5 timebase steps when zooming. 12Mbyte means about 14 steps (1Mbyte means 10 steps).

??

I have no idea what you're calculating there. How can 500 times more memory only give 2 or three more steps?

 

Offline pxl

  • Regular Contributor
  • *
  • Posts: 126
  • Country: hu
Re: Are old digital scopes worth the money?
« Reply #44 on: March 29, 2016, 04:58:53 pm »
24k memory means approx 5 timebase steps when zooming. 12Mbyte means about 14 steps (1Mbyte means 10 steps).

??

I have no idea what you're calculating there. How can 500 times more memory only give 2 or three more steps?

Every zooming steps require 2 times memory. Let's suppose one screen is 600px, then log2(24000/600)=5.32, log2(1*10^6)=10.7,   log2(12*10^6/600) = 14.28
 

Offline Fungus

  • Super Contributor
  • ***
  • Posts: 12373
  • Country: 00
Re: Are old digital scopes worth the money?
« Reply #45 on: March 29, 2016, 05:49:37 pm »
24k memory means approx 5 timebase steps when zooming. 12Mbyte means about 14 steps (1Mbyte means 10 steps).

??

I have no idea what you're calculating there. How can 500 times more memory only give 2 or three more steps?

Every zooming steps require 2 times memory.

Oh, I see.

Yes, 2^9 = 512

That's a weird way to look at it though. Nine logarithmic steps is a lot more information (remember the story of grains of rice on a chess board).

Plus ... it doesn't have to sample at 1GHz. I can turn the time base/sample rate right down and record a signal for quite a long time (minutes!) That's useful for looking at RS232, etc.

 

Offline Howardlong

  • Super Contributor
  • ***
  • Posts: 5105
  • Country: gb
Re: Are old digital scopes worth the money?
« Reply #46 on: March 29, 2016, 06:51:27 pm »
FWIW for a while I had a 54622D and an MSO1074Z, and the 54622D was used much more than the Rigol. Why? Mostly it's down to the UI, how immediately responsive it is and how ergonimic it is to use, everything is obvious, in your face, no random button pushing to find things. I liked it so much I upgraded to a 54642D, the 500MHz 2 GSa/s version. 5 second boot time was also a good reason to prefer them, although I know some don't think this facet means much to them, but being a mixed signal firmware type I don't tend to have my TE switched on all the time.

FWIW, the 54622D is 4Mpt and the 54642D 8Mpt, so this matches or exceeds the current x3000 series (4Mpt) from Keysight. These 15 tear olds also have plenty of modern stuff like built in serial decoding and triggering.

Although it's a bit more snazzy, the fundamentals of the UI from those scopes comtinue to this day, even though the underlying OS went from VxWorks to Windows CE. The key principles of a simple, self explanetary and fast UI remain.

 

Offline robert_

  • Regular Contributor
  • *
  • Posts: 151
  • Country: de
Re: Are old digital scopes worth the money?
« Reply #47 on: March 29, 2016, 07:52:48 pm »
I still work with an old Lecroy 9354L from time to time.
Its certainly no useless or "shit", the more advanced functions are somewhat non-intuitive to use but at least THEY WORK. And there are a LOT of these that will come in handy from time to time.
2M/ch certainly isnt bad, nor is the ability to use math over the full memory, and quite deep FFT (iirc 1M or so, gets fairly slow but it does work properly). Advanced trigger modes work fine too, reducing the need for stupid "manual glitch detection" with ultra-high wfm/sec.
Also i didnt have that thing crash or find a problematic bug yet, as opposed to pretty much any low-end scope (or anything made by Tek no matter how expensive) i ever had the displeasure to work with.
Try to find one with a CPU3 card as these are a lot faster (48Mhz 68030 vs. 16Mhz 68020) and can run newer FW with more features (upgradable via floppy drive on these, older ones are EPROM).

Stuff is quite repairable too, you get a full service manual for it and most of the "common" problems are fixable. No "leaking SMT capacitors killing the entire board" or "unobtainium hybrids failing like flies" type of fail as with some other scopes of that time. Floppy drive breaks often, but its replacable with a common laptop floppy drive for <5bucks.

So yeah, the better models from the 93xx series probably are worth more than a DS1054.

Things to stay away from:
Most TDSxxx (short memory,slow, many are terribly unreliable, close to unrepairable)
TDS1xxx, TDS2xxx (short memory, nothing but extremely basic festures)
All Tek if its broken, no service manuals for almost all of them
large-case HP greenscreens with that single encoder wheel (too old, unuseable UI)
Lecroy 7200 (wayyy to old and HUGE)
Lecroy 9400 (too old, too little features)
Most analog/digital combiscopes (too little memory, too limited features, except for some newer hamgs that are quite decent)
 

Offline firworks

  • Supporter
  • ****
  • Posts: 22
  • Country: us
    • Firworks
Re: Are old digital scopes worth the money?
« Reply #48 on: March 29, 2016, 07:56:34 pm »
I spent a long time looking for a deal on the LeCroy 93X4Ls and wasn't able to find anything. I still do look though and might grab one if I find it to complement my new Siglent. You never know what will come in handy some day. One day while working on an issue we had a MSO with 4 channels and 16 channels digital chain triggering another 4 channel scope and a 2 channel analogue scope to solve a particular issue. It was quite the frankenstein setup but it worked.

Also I'm sort of drawn to the LeCroys because I love the orange screen. It looks too cool.
For fun, for information? http://firworks.net
 

Offline Wuerstchenhund

  • Super Contributor
  • ***
  • Posts: 3079
  • Country: gb
  • Able to drop by occasionally only
Re: Are old digital scopes worth the money?
« Reply #49 on: March 29, 2016, 08:18:54 pm »
I spent a long time looking for a deal on the LeCroy 93X4Ls and wasn't able to find anything. I still do look though and might grab one if I find it to complement my new Siglent.

Have a look a the LC Series, it's essentially a 9300 with color screen and much faster processor. With some luck you might find one of the CRT ones (LC 3xx/5xx) for roughly the same or maybe even less than a higher spec 9300.

The LC 500/600 were also the first scopes that were also sold as Disk Drive Analyzer (DDA). It's essentially a LC with the DDM option preinstalled and is regularly overseen by punters who often think that this is only something for doing stuff with hard drives and worthless for anything else.

Also, with some patience you can sometimes even find a WaveRunner LT for a low price.
« Last Edit: March 29, 2016, 08:25:40 pm by Wuerstchenhund »
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf