What kind of 'scope to buy?

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Hey freaks,

my tests will be over next month and I'll have some time to work on the 10x10x10 LED cube project. My current oscilloscope is USB based (no screen) and has a bandwidth of 10 MHz. Unfortuantly it is unable to trigger anything at all :(

My budget is about 350€, maybe more if I'm able to give some private math lessons. Since thats quite a bit of money for me and because I'll have to stay with that scope for at least a year I'd like to get some advice.

What kind of scope would you recommend? I'm doing standard logic stuff. No radio or such. My current fastest parts are 20 MHz AVRs. But I plan to buy one of those FPGA starter kits at the end of the year.
http://www.trenz-electronic.de/d...
Aim is to learn FPGA programming.

Would you guys get a USB or stand-alone scope? Is there anything I have to watch for, despite price, bandwidth and number of channels?

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I use an old 100 MHz Tek 2235 analogue scope. They can be picked up quite cheaply. Apart from the timebase switch going intermittent (Tek used a PCB switch to save money, and they aren't available as spares), they are very reliable.

Leon

Leon Heller G1HSM

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I have an old/good Tektronix 465.
And a $130 USB 'scope, 40MHz. China-direct. Hantek DSL2090. Beware: US Retailers markup by 40%.

each form has its place! The digital scopes are essential for non-recurring (triggered) waveforms like bus signals, SPI/I2C, etc.

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I have a 465 I got at Skycraft. That was the Standard for about two decades. AT work we have a couple of those Korean 100mhz Softscopes which seem good except for the occaisional sw-takes-a-poop dialog box. Expensive though.

Imagecraft compiler user

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You already got one of the standard recommendations, buy a used Tek. Used oscilloscopes (from eBay) of course come with a risk.

Let me add a few more recommendations.

Nephazz wrote:
My budget is about 350€, maybe more if I'm able to give some private math lessons.
I'd recommend you do so. The larger your funds are, the more options you have.
Nephazz wrote:
Since thats quite a bit of money for me and because I'll have to stay with that scope for at least a year I'd like to get some advice.
350+ Euro should buy you an oscilloscope that is good for more than just a year :-)

Nephazz wrote:
What kind of scope would you recommend?
If you buy a new one, I'd recommend a DSO. Analog scopes do have advantages, and there is nothing wrong with them, but you should get more features for your money with a digital scope.

Your funds should make it possible to get a new GW Instek DSO or Rigol DSO from the lower end of their offerings. The quality is good enough for years to come. A UNI-T or Owon DSO should be cheaper, but I find their quality at the border of what I find acceptable.

Nephazz wrote:
Would you guys get a USB or stand-alone scope?
Stand-alone. Always stand-alone. This is because I am old fashioned and need real knobs on an oscilloscope, but also because USB oscilloscopes depend entirely on the PC software. The moment a Windows service pack or a new Windows version breaks compatibility, and the oscilloscope supplier doesn't do an update (or is no longer around) you have lost the whole oscilloscope. There are also safety issues. Cheap USB oscilloscopes don't have any serious isolation between the scope and the PC.

Nephazz wrote:
Is there anything I have to watch for, despite price, bandwidth and number of channels?
Noise floor comes to mind. Probes. Display quality, build quality, and maybe hundred other things. All oscilloscopes have limitations. You'll have to live with the. Some issues are a matter of personal taste. For example, if the stand-alone oscilloscope has a PC interface I require the interface protocol is documented.

Stealing Proteus doesn't make you an engineer.

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I got a new Rigol DS1052E on ebay for ~$500 USD about 4 months ago, it is a DSO with 1M sample memory and 50mhz bandwidth. 50Mhz might be a bit low for FPGA, but then again for FPGA you are probably better off with a logic analyzer.

I am impressed with the quality of the Rigol scope, everything works without problems, I also find the user interface very intuitive.

Rigol is supposed to be an OEM for Agilent, some of the Agilent scopes are supposed to be rebranded Rigol scopes.

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Yes, Rigol makes the low-end Agilent scopes.

Leon

Leon Heller G1HSM

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perhaps a UT 2042 C from Reichelt ?

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Thanks for all your thoughts and scope name postings. Gives me stuff to work with. Standalone DSO is the way to go for me I guess. For all the reasons already stated, plus: It looks waaaay more balla than a little grey box with some cables :D

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I have the Rigol DS1102E scope. It isn't as good as the scopes at work (obviously) but I like it for hobby use.

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The only problem I have with my Rigol is that for single trigger capture you can not apply a digital filter on the data.

Rigol seems to hit the sweet spot in terms of price vs performance and features.

Standalone is the way to go right now, looks cooler and is generally easier to use which increases productivity. When USB 3.0 rolls out though the game will probably change as it would allow for a 10x improvement in bandwidth, USB 2.0 seems to be limited to 250M samples/sec.

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toalan wrote:
The only problem I have with my Rigol is that for single trigger capture you can not apply a digital filter on the data.

Rigol seems to hit the sweet spot in terms of price vs performance and features.

Standalone is the way to go right now, looks cooler and is generally easier to use which increases productivity. When USB 3.0 rolls out though the game will probably change as it would allow for a 10x improvement in bandwidth, USB 2.0 seems to be limited to 250M samples/sec.

the sample rate is unrelated to the PC interface speed.

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I've got myself a UT2042C from Reichelt

40 MHz, color display, PC connection, 2 channels for 350€ :)

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Good value for money ! And I envy you for the USB-connection :) Send us a nice screenshot or so :!:
I bought a Tek TDS2022 last year, but hélas, without PC connection.

Nard

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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stevech wrote:
toalan wrote:
The only problem I have with my Rigol is that for single trigger capture you can not apply a digital filter on the data.

Rigol seems to hit the sweet spot in terms of price vs performance and features.

Standalone is the way to go right now, looks cooler and is generally easier to use which increases productivity. When USB 3.0 rolls out though the game will probably change as it would allow for a 10x improvement in bandwidth, USB 2.0 seems to be limited to 250M samples/sec.

the sample rate is unrelated to the PC interface speed.

I assume that most usb based scopes are just a fast ADC that pushes data to the PC for processing via the USB port.

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Bought a "OWON" PDS5022S (25mhz) scope for £170. It is /brilliant/ compared to my old usb based one. Of course it's not a tek, but it has USB interface and pretty much anything I'd want of a scope for "mainstream" use.

Author of simavr - Follow me on twitter : @buserror

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Good to hear that :)

It's so hard to design and build AND debug designs without a scope. I used a pretty old Philips 50 MHz analog scope with a not-perfect channel A for years, but in spite of the little cripple, it was TEH tool.

Because my Tek (as the UT2042) have a limited depth of 1024 samples, I sometimes need the analog scope to debug: very intermiitend glitches are easier to catch with that old analog scope than with the digital one.

Nard

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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@nephazz
How is your experience with that scope ?
Are you satisfied ?

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I've tested it yesterday with two square waves out of a mega. My experience so far:

If you change the time base of channel A it automatically changes the time base of channel B. I hope I can change this.

The probes are standard and nice to handle. The software looks a little grey, didn't use it though. The buttons are nice to push, knobs turn infinite, good to position. The menues are straight forward and I was able to get started without the manual. I've been using it for 30 minutes and I really like it so far.

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Nephazz wrote:
If you change the time base of channel A it automatically changes the time base of channel B. I hope I can change this.
This is absolutely normal for oscilloscopes of this class. You won't find a second time base in these oscilloscopes.

The usual workaround is to use the "S" in DSO (the storage), and investigate the signals with the windowing / zooming functions.

Stealing Proteus doesn't make you an engineer.

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I own the Tektronix TDS2014 4 channel/100MHz oscilloscope. Although it has a small LCD I find it very good and easy to use.
In the R&D dept. I work, I use the MSO2014. Guys, I find it very bad for a lot of reasons. It is not user frienly as it might be.

Michael.

User of:
IAR Embedded Workbench C/C++ Compiler
Altium Designer

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In the late 1990's I bought a 100MSa/s Link Instruments DSO-2102. It is PC based and attaches through the parallel port. It has worked well.

Since the O-scope was discontinued before Windows Vista came, Link Instruments never bothered to update the PC software to run on the Vista. So, I need to keep an XP machine in the lab. VERY annoying. (this makes me very leery about buying another PC based scope)

Matt

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matt6ft9 wrote:

Since the O-scope was discontinued before Windows Vista came, Link Instruments never bothered to update the PC software to run on the Vista. So, I need to keep an XP machine in the lab. VERY annoying. (this makes me very leery about buying another PC based scope)

Matt

Just run XP under VMware or Virtualbox.

If you use linux, you can even
put linux on an external USB drive.
When you do this, you can then have all the
s/w on an external USB drive and you can plug
that usb drive into *any* PC and boot it up.

It is a nice self contained environment
that is not attached to any machine.

--- bill

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Hi,

I've got a Rigol MSO I am quite fond of - 2 channels and a 16 channel logic analyzer.

Good luck,

Alan

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I'm having hard time choosing entry-level DSO, for general digital use, <100Mhz, 1Gsp, 2ch. My budget is <= $2500 but I try to spend as little as possible.

Should I go for Tek TDS1012B (b/w screen) or Instek (GoodWill) GDS2102? They have the same screen, somehow same options, but Instek is almost 40% cheaper than Tek. As it's name says, buy me instead of Tek = Instek :).

Why I would not buy (Ins)Tek? Both has 320x240 screen, maybe it is too small for small signal reading. Could have to scroll forever when debugging USART. Next reason is both have short buffers (2kpts for Tek, 10kpts for Ins).

On the other hand, Hameg HM1008 has analog+digital mode, 1Gsp, 1Mpts buffers, is almost same price as Tek...

But I'm afraid of the CRT: super-bulky, could be easily broken, and lack of screensaver could burn the HUD readouts. Also I couldn't find any info about Hameg's warranty. 1-2 years could be potential waste of huge money. Couldn't find any user reviews, no forum topics whatsoever about the new combo hamegs. Judging a company by it's website content, I guess Hameg is dead for a long time...

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What I ask you may seem a little silly: How
experienced are you in electronics ? Are you
able to bring a 100MHz signal into the scope
without to much error ? Is this scope for
private use or use by many people in a company ?

An experienced guy having a budget of 2500$ would
certainly spent the whole budget for an oscilloscope
and try to get the best for the money.
But if you only want to make relatively simple
meausrments in lower frequencies (<30MHz), it is
perhaps enough to buy a 1000$ scope and spend
1500$ for other nice measurement equipment.

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I agree with ossi. I bought a refurbished*) Tek TDS2022 for €1200 incl VAT and import duties. If I had another chance of choosing a scope, I'd go for the Rigol-series: very good value for money.

Nard

*) Refurbished: it was brandnew ;)

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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I own a small company and been servicing and designing electronics and electrics for 5 years now, and just starting to see how much I've been missing not having a scope. I'm the only one in company who will use it, and will forbid anybody else to come close to it.

Max frequency I would ever measure is 20Mhz (cpu clock). So I multiply it by 5 and decide a 100MHz DSO should not give me problems. All other digital buses / interfaces are operating at smaller frequency.
Other than digital, I would use it for testing of transients and noises coming in and out of PCBs and electric cabinets (troubleshooting relays, contactors, DC noise, etc).

You guys think I should go for 60MHz scope?

I got an impression that 2.5kpts of memory buffers isn't enough for recording single-shot transients or checking out I2C messages..

Instek GDS-1102A seems like a perfect buy. Everything like a TDS2012 but with 2Mpts buffer, somewhere around 950$. I could live with 500Gsp both channels active, 1Gsp single channel.

* edit: 60Mhz scope, not 60Hz :oops:

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Quote:
You guys think I should go for 60MHz scope?
No. It's a long term investment. And if you run a company: even more reason to go for the best you can afford.

Added:

Quote:
I got an impression that 2.5kpts of memory buffers isn't enough for recording single-shot transients or checking out I2C messages..
Exactly. That's the only drawback on the Tek I have.

I suggested you the Rigol. There are models that include a logic analyzer. How much better does it get ? ;)
Btw, I purchased the Intronix Logic Analyzer last year. 32+ channels. Nice tool, but I could live with 8 channels on the scope.

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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...just comparing...

Rigol
DS1102CD: 16-ports logic analyzer, 100Mhz, 1Mpts buffer, but only 400Ms/s single channel, 200Ms/s with logic analyzer. Born for digital stuff.

Instek
GDS-1102A: 100Mhz, 2Gs/s, 2Mpts buffer. I miss integrated logic analyzer. Could buy an Intronix logic analyzer and solve both problems.

Hameg & Tek are out of ring.

Will check the Rigol prices and report back.

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Bump.

And since this thread seems to have died a little, ill do a little highjack. Im looking for a scope for my hobby lab myself and it looks to me like the Instek GDS-1062A (http://www.aspen-instek.com/01-digital-osc.html) may be the way to go - any experiences? Or other suggestions?

I think its a bit expensive as i will have to pay 25% VAT to get it in to Norway, but i guess oscilloscopes dont come cheap in any case.

Any comments or suggestions are very welcome.

Thanks,
Alexander

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My recommendation: an oscilloscope is an investment that will serve for decades. Don't go for the cheap, but give it a good budget. You will never regret it.

O .... I just notice (scrolling back) that I said that already.

Quote:
i will have to pay 25% VAT to get it in to Norway
To the Netherlands it's 20% VAT + a few percent for shipping company.

Buying it in a Norwegian shop, those costs all in the price included. So you get bitten by the cat or by the dog .... but you *get* bitten.

Recommendations plenty in this (and other) thread(s)
What can you afford, budgetwise ?

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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Well, im not willing to spend too much as im just doing AVR related projects.

I might go for something like the GDS-1022 (http://www.instrutek.no/productSheets/GoodWill_GDS1022-WEB.pdf). I would be able to buy that here in Norway for about 275 GBP (3000,- NOK) not including VAT. That seems like a pretty good price as they are currently on a special discount.

What do you think, does it look alright?

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In a few years time you will find that 25MHz is not enough.
No upgradepath .... , so you either struggle on, or buy another scope.

That's more expensive, don't you think ?

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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Bit the bullet, cried a little, and bought a Hameg HM1008-2 2x100Mhz Combiscope. I don't think it's the best price-performance I could buy in all the forest, and my back pocket will hurt for few years. But it has an extra analogue scope inside, and a component tester. The screen has 2000-dots of horizontal resolution and a fast 50mS/div roll mode. Screen update speed (with 2 traces + math displayed) is little over 150Hz. Oh well...

User manual is totally horrible also. It puts me in a black mood. Manuals shouldn't be written like a bloody advertising pamphlet. Instek user manuals are eons ahead in user-friendliness, and show exactly what the scope is capable of. Hameg's tech writers should know that many buyers read the user manual cover-to-cover BEFORE they buy the thing. Some even before they buy their first scope.

I hope the 'envelope mode' (extremely undocumented) will be good enough replacement for Instek's 'accumulate' feature (Rigol & Tek call it 'Persistence'). And the whole thing looks like a 80x86 desktop computer, just without the fans. It will be a PAIN to carry it around in dark, dusty, and horrible places I roam sometimes. Not to mention, to keep it intact.

BTW, some time ago I searched all over the net and couldn't find any hi-res images or video of new combiscopes in action, so when it arrives I'll post some pics.

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If I had not had a company who lives from electronics and industrial stuff... If I was just a hobbyst... I would certainly go for the cheaper thing.

Now, I have a different opinion: in 20 years, Chinese or Indus could sell 4 x 200Mhz scope for the same or half the money you now invested in 25Mhz scope. Chips advance, engineering advance, Far East advance. Timing is very important. How fast you plan to develop your product?

If you could afford some extra $$$, then go for the cheapest Instek with 2Gpts memory - here it's almost same price as the one with 2kpts (our distributor offers some special discount).

rg2720 wrote:
Well, im not willing to spend too much as im just doing AVR related projects.

I might go for something like the GDS-1022 (http://www.instrutek.no/productSheets/GoodWill_GDS1022-WEB.pdf). I would be able to buy that here in Norway for about 275 GBP (3000,- NOK) not including VAT. That seems like a pretty good price as they are currently on a special discount.

What do you think, does it look alright?

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@kvlada

Indeed, manuals can be a big pain in the ....
Good news is: once you get to know your scope (and that will not take THAT long), you will no longer need it.

Did you buy it for a good price ? Second hand ?

Quote:
It will be a PAIN to carry it around in dark, dusty, and horrible places I roam sometimes. Not to mention, to keep it intact.

You got me puzzled here: when you KNOW on forehand you'll have to carry it around in evil places, how on earth did you decide to go for the Hameg ?

You're not a gynaecologist by any chance huh ?

Nard

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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Say, I want to see the 380V R-S-T phase voltage.
Or check the drops in 230V wall-socket in roll-mode.

The scope has CAT-I 400Vpp input.

Then I would have to buy a CAT-III 1kV differential probe with 100x/1000x attenuation?

Or I could get away with a 100x 2.5kV high-voltage passive probe?

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Quote:

Did you buy it for a good price ? Second hand ?

New. I think the price is good. It is the ordinary factory price (I found it everywhere on the netshopt) plus VAT and transport. The only way to buy a Hameg it is from a distributor. They don't sell directly...

Quote:
You got me puzzled here: when you KNOW on forehand you'll have to carry it around in evil places, how on earth did you decide to go for the Hameg ?

Well you said I go for the best for the buck.
Just kidding. :D
What were my alternatives? Every scope has knobs and buttons and sensitive screen. Instek is smaller, lighter, but is easily destroyed - if you leave it in a coal plant or near paint job, fan will inject nice conducting particles inside. On the other hand, humidity could wreck havoc on the 14kV CRT.

Distributor said if something happens they will ship it to Germany by courier, what is much faster than waiting 30+ days for Instek to be serviced to and from Taiwan.

Fluke's hand-scopes are almost double-price than Hameg HM2008 (2x200Mhz+logicprobe) and are less performance.

Chinese hand-scopes with 160x120px lcd are out of question, as I need something sensitive to be used in the lab, not just in field.

Quote:
You're not a gynaecologist by any chance huh ?

:P
We do both mechanical and electric stuff. So, it gets quite greasy sometimes.

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kvlada wrote:
If I had not had a company who lives from electronics and industrial stuff... If I was just a hobbyst... I would certainly go for the cheaper thing.

Now, I have a different opinion: in 20 years, Chinese or Indus could sell 4 x 200Mhz scope for the same or half the money you now invested in 25Mhz scope. Chips advance, engineering advance, Far East advance. Timing is very important. How fast you plan to develop your product?

If you could afford some extra $$$, then go for the cheapest Instek with 2Gpts memory - here it's almost same price as the one with 2kpts (our distributor offers some special discount).

rg2720 wrote:
Well, im not willing to spend too much as im just doing AVR related projects.

I might go for something like the GDS-1022 (http://www.instrutek.no/productSheets/GoodWill_GDS1022-WEB.pdf). I would be able to buy that here in Norway for about 275 GBP (3000,- NOK) not including VAT. That seems like a pretty good price as they are currently on a special discount.

What do you think, does it look alright?

It actually has 4000 points memory, the one i nliked to (GDS-1022). You dont think this will be enough? You see, the price gap between this model and another more advanced is huge - about 100% more expensive.

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kvlada, apparently you went through an extensive selection process. As a result, the Hameg came out as the best for your budget, needs etc.
It doesn't get better, so I hope you will be pleased once you have the scope on the lab-desk.

In the days I ran around with a simular scope, I put on the hard cover that fits over the front. That protects screen, knobs etc. On top of the scope a soft "suitcase" for mainscord and probes. That worked fine for me.

Quote:
Say, I want to see the 380V R-S-T phase voltage.
Or check the drops in 230V wall-socket in roll-mode.

The scope has CAT-I 400Vpp input.

Then I would have to buy a CAT-III 1kV differential probe with 100x/1000x attenuation?

Or I could get away with a 100x 2.5kV high-voltage passive probe?


Hmm. Not a simple one.
Your scope has a mainsplug with Safety Ground (SG) connection. That means that the groundclips of the probes are connected to SG as well. And there is where it gets tricky.
When you have to do measurements on a 3-phase system, with floating null, and you connect the groundclip of a probe to that null .... a large current can go through your scope. Which can result in a Booom, a Flash or any other bad thing.
A differential probe looks like the best way to go, but I do have my doubts.

There is a huge amount of knowledge here on Freaks, so I hope a fellow freak will pop in and provide a solid and conclusive answer.
In the mean time I will ask around and see if I can come up with something.

Nard

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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Quote:

Which can result in a Booom, a Flash or any other bad thing.

When I was still at school I went for a two day "electronics workshop" at Queen Mary College - a part of London University. While there, sadly I learned the "Boom/Flash" lesson the hard way :oops: - which probably explains why I'm now a software engineer rather than a hardware engineer! :lol:

(I've never had an explosion as a result of a mis-placed semi-colon on line 42 ;-))

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@rg2720:

My distributor offers:
25Mhz, 4kpts, 250Msps, GDS1022: 362€
60Mhz, 4kpts, 250Msps, GDS1062: 494€
60Mhz, 2000kpts, 1000Msps, GDS1062A: 563€

There is a small difference between 1062 and 1062A. If you can afford the 1062, then add a little more and get the 'A' model, it is a real mean machine.

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OMG the passive probe would make a barbecue. Common ground. I used to be more smarter than that...

So it's either an isolated differential probe, or to try measuring with current transformer.

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kvlada, don't despair ... help is on its way.
I asked tpappano for his insight and consulted my brother in law, who knows a LOT on power-systems, transformers and such. We'll get there ...

Nard

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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Hi all,

My inclination would be to just get a pair of x100 passive probes, and using the differential input mode of the scope itself, measure the voltage between the probe tips. That way you can safely measure phase to phase, phase to ground, etc. while the scope itself remains safely grounded.

Being somewhat frugal myself, for the last 26 years I used a little Hitachi V212 2ch/20mhz scope daily, and which was powered up 24/7. The phosphors finally faded so much I switched to an old Tek 7603 4ch/100mhz someone gave me for regular bench use. Really nice old scope. I still drag the Hitachi around for field work, though it is getting pretty hard to see 8-)

Tom Pappano
Tulsa, Oklahoma

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Buy a used scope, more bandwidth, cheaper unless you need a huge amount of samples, then get a DLA or whatever.

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I rented a Tektronix TDS1012 for $50 per month. Is is the size of a small radio or boom box. LCD display on the left and knobs on the right. Its pretty nice.. It has buttons to toggle options live while looking at a wave such as positive time or negative time of the square wave. It is fun when looking at PWM as you can check the on versus off time. The size is great compared to my old Hitachi 4 channel which has bad contacts in the level switches. I should have rented the RS232 module which is an optional plug in to get data out.

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Hi,

The scope I use (and love) is on sale here:

http://www.globaltestsupply.com/...

It is only 25mhz, but is a MSO (mixed signal oscilloscope) and has a 16 channel logic analyzer build in as well. Retail was $700 when I bought it. I don't know if they have any in stock, but it is a good price for a MSO.

Good luck,

Alan

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I promised to post some pics, so here we go...

My first doubt was the DSO "persistence" mode, will it work as on classic LCD scopes?

And the answer is yes and no. Here we see a clocked bus reply from a 24-bit A/D. The last few bits are noise, so they are constantly changing 0-1, and so are smelted in a big glob of glowing phosphor. I would expect to see something like a grid (formed by SDA changing up-down) but this is also usable.

Next, zooming an RS-232 bus communication, checking for glithes. The zoomed part has higher intensity. Unfortunately CRT is monochromatic...

I call this "nostalgie-mode" (switched to analog, readout off)
but now you don't know what're you watching, since only readout is digital, on screen. Dials are rotary-encoders (not pots) and smaller ones are a harder to rotate than larger. Larger have tactile feedback per step.

At last we have a nice component tester, drawing a diode characteristic

Now, the overall impression is that it's not too heavy. When I lifted the box it seemed like it was half-empty. Seems like I did too much workout on heavier, dumber hardware.

The user interface is somehow spartan. There could be only 1 automatic measurement and 1 cursor measurement on screen at once. If I had to measure both frequency and Vpp I'd have to switch from one reading to another using menus.

Probes that came with it look cheap. They're fixed to 10x, so there could be some probe shopping in near future. The inputs are really CAT I, so I'm thinking about powering the whole lab's measuring equipment from a 300W isolating transformer.

I miss the crispness of a LCD screen. But then, I get BMP screenshots in 500x400 resolution. Not close to specification ("2000 dots in horizontal screen resolution" says the datasheet) but somewhat better than 320x240 screenshot. Funny thing, the screenshot is black&white. I would expect to display channels in different color.

Trace intensity isn't automatically controlled in digital mode. I find myself constantly turning it up and down as I change horizontal resolution. It really scares the hell out of me when it abruptly turns intensity to max when I turn something on. Guess some scopes like better to burn out then fade away...

The thing really has no fans, and produce no noise when running (except the relays clicking).

Only thing I'm worried about is when moving from test site A to test site B, that are close by, I'd have to unplug power cord and plug it again somewhere else. User manual says this is a horrible abuse of the CRT heater, to turn power on and off. Maybe I'm going to strap an UPS to it - could add some extra kg but as I said earlier, I can carry it all with no problem.

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Thanks for showing us, kvlada !
In the meantime I also got an answer on measuring 380V 3 phase and such: like expected: use two probes, and set the scope up in differential mode: invert B and sum with ch A.

Nard

A GIF is worth a thousend words   They are called Rosa, Sylvia, Tessa and Tina, You can find them https://www.linuxmint.com/

Dragon broken ? http://aplomb.nl/TechStuff/Dragon/Dragon.html for how-to-fix tips

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