Author Topic: what an oscilloscope recommended for a woman passionate about electronics?  (Read 53162 times)

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Offline CharlotteSwiss

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Important note for those wishing to buy this 1202x-e Siglent oscilloscope: I verified that with the latest firmware it has blocking problems by saving an image on a USB key; no problem with the penultimate firmware. If the engineers do not release further firmware after 1.3.26, I do not recommend purchasing this device!

-----------------

Hello, I'm Charlotte and I live in Switzerland  :)
I work in the hospital, but my hobby is electronics; i try to repair electrical devices, 99% of the time I don't solve the problem, but that's okay
 ^-^
Women usually read gossip magazines  :-//
but there are women who prefer to make love with electrons  ^-^
My equipment is: soldering station, two multimeters, bench power supply.
I'd like to start a seductive relationship with an oscilloscope..   :palm:
I don't want to spend too much, but I don't want to buy the worst...
For example the model Rigol ds1052E is ok for beginner woman? or better Rigol ds1202z-e (200mhz) ?
Other brands on these prices?
Do you have any advice for me? i am in your hands...
thanks
Charlotte
 ^-^

« Last Edit: June 23, 2021, 09:12:44 am by CharlotteSwiss »
 
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Offline AVGresponding

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Does it have to be a new one?

I am passionate about vintage/used test gear...   :-DD

If you have a precise use case, it might be easier to recommend something.

Repairing battery items? Repairing mains powered items? Playing with PIC/Arduino/PI? General circuit design and experimentation? Playing with RF equipment?

Those are just a few examples, and all mean a slightly different oscilloscope specification.

In any case, welcome to the EEVBlog forums!
nuqDaq yuch Dapol?
Addiction count: Agilent-AVO-BlackStar-Brymen-Fluke-Hameg-HP-Keithley-IsoTech-Mastech-Megger-Micronta-Racal-Siglent-Solartron-Tektronix-Thurlby-Time Electronics-TTi-UniT
 

Offline sahko123

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A ds1052e can be upgraded for free as well as the DS1054z with very little effort so id recommend the latter
Asking for a friend
 

Online tggzzz

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The same scope as would be recommended for a man passionate about electronics, of course :)

More seriously, any working scope is better than none. You will pay to gain experience with your money and your time. There is an argument that experience with a cheap working scope will enable you to understand what you actually need.

More importantly, for safety's sake make sure you understand the different types of probe and when they can be used and when they must be used. And why you should never disconnect a scope's earth lead. FFI, see the references at https://entertaininghacks.wordpress.com/library-2/scope-probe-reference-material/
There are lies, damned lies, statistics - and ADC/DAC specs.
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Offline rstofer

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This comes up about every week but generally from a male perspective which I think is totally irrelevant.

You talked about repairing gadgets but not which kind of gadgets.  You didn't mention microprocessors or FPGAs.  Those factors point to a required bandwidth.

The most popular recommendation over the last few years is the Rigol DS1054Z because a lot of the uC projects are easier to troubleshoot with 4 channels - like SPI protocol.  Others will say you should just use a logic analyzer and that's also a nice tool to have around - after the scope.

Today, the Siglent SDS1104X-E seems pretty popular as it can be unlocked to 200 MHz and has 4 channels and purportedly a better user interface (more responsive).  Since I spend less that 1% of my scope time using the UI, I'm not sure I care.  The Siglent is more expensive

https://www.amazon.com/Siglent-SDS1104X-oscilloscope-channels-standard/dp/B0771N1ZF9   $498
https://www.amazon.com/Rigol-DS1054Z-Digital-Oscilloscopes-Bandwidth/dp/B012938E76   $362

ETA:  I have no idea what the prices are in Switzerland.  I should have paid more attention to the country flag.  OOPS!

If you use the search feature, you will find the other threads and recommendations are all over the map based on price (generally).

You didn't bound the price so, again, there's not enough information.  If you want something off of eBay, that's a different conversation.  If you want a USB scope, another topic.

If I were learning electronics (other than that which I learn just about every day), I would hope I was smart enough to consider the Digilent Analog Discovery 2. There are 4 learning experiments in the following thread, producing what I consider to be important results, that are darn hard to produce with an oscilloscope and waveform generator.  That's because the Bode' Plot is in the frequency domain (x axis is frequency - actually log(frequency) ) and a scope usually works in the time domain (X axis is time per division).

Look at Reply 54 here:  https://www.eevblog.com/forum/testgear/starter-scope/50/

https://store.digilentinc.com/analog-discovery-2-100msps-usb-oscilloscope-logic-analyzer-and-variable-power-supply/

You really can't ask the "which scope" question without bounding the replies.  Keysight makes at least one scope that costs $300k.  I assume that it is off the table.

Bottom line:  If I were in the market for another scope, it would be the Siglent SDS1104X-E.  It can be unlocked to 200 MHz and has 4 channels.  The Rigol DS1054Z can only be unlocked to 100 MHz and bandwidth is the most important specification - except channels.  I like my Rigol  a lot but when I'm playing with learning circuits, I use the AD2.

« Last Edit: June 19, 2020, 02:04:23 pm by rstofer »
 
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Offline CharlotteSwiss

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thanks  ^-^
-avgrespondic: i would like to buy new, I prefer
I try to fix anything on a basic level: audio device if don't start, any household appliance, power supply... nothing difficult.
my intention is to start studying the oscilloscope starting from the basics  ^-^

-Sahko123: but ds1054z is 4 channel, is not inconsiderate for me? 2 channel is not sufficient?  :-//

-tgzzz: thanks for warning! in general I am very attentive to safety, Every time before operating I discharge the capacitors using my special kit.
 I will be well informed on the use of the probes  ^-^

-rstofer: as price range I had indicated rigol 1052 or max 1202z-e (similar price..)
The siglent 1104 it's too much money for me  :-// :-\
I don't make electronic plans.. I only do troubleshooting on the electronic boards
Now I only use multimeter and power supply bench, but I would like to learn to find faults also using the oscilloscope.

I would like to understand:
- for my use, is not sufficient 2 channel?
-for my budget, the bandwidth range is 50 to 200 max mhz... with 200 mhz I have many more possibilities (compared to 100mhz?)
 For example the microprocessors in my amplifier work a 20mhz..

I want to start playing with the oscilloscope from the simplest things, your buying advice is very useful

Charlotte  ^-^
 

Online RoGeorge

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Rigol DS1052E is 300€, Rigol DS1054Z is 400€ at Batronix (probably the best seller in EU, very good prices and outstanding customer treatment, I baught from them 3 different Rigol instruments), all taxes included.
https://www.batronix.com/shop/oscilloscopes/Rigol-DS1052E.html
https://www.batronix.com/shop/oscilloscopes/Rigol-DS1054Z.html

I'll buy the DS1054Z because it's a newer model, can measure more things, has more memory, and also has 4 channels that you might need one day, and in case you'll want to sell the oscilloscope, a DS1052E will be much harder to sell than a DS1054Z.

Offline CharlotteSwiss

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thanks rogeorge
sure, but ds1054 costs 1/4 more...
My range price is: low ds1052 / top ds1054 (but it's already a lot for me...)
Ds1054 is 50Mhz.. but with a magic wand work to 100mhz..

I have seen that nobody takes into consideration rigol ds1202z-e... all smoke and no roast?  :o

 ^-^
 
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Offline Benta

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I'd say you need two scopes for what you want to do:

An old-fashioned analogue/CRT 'scope, 20 MHz is enough. Should be easy to find one used for cheap. The analogue 'scope allows you to see details in the signal that drown in the quantisation of DSOs.

And of course a DSO with enough sample depth.

I have both and couldn't live without either of them.

 

Online fcb

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Don't bother with an analog scope.

DS1054Z 100%

Doubles as a handbag, something an old CRT 'scope won't.

**New USB Picoammeter available now**
https://electron.plus Power Analysers, VI Signature Testers, Voltage References, Picoammeters.
 
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Offline CatalinaWOW

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There are no hard answers.  My hobby needs were similar to how you describe yours and I survived for decades with a two channel 2Mhz bandwidth oscilloscope.  There is much to be fixed within those limitations.  Even though processors are clocked nowdays at far higher rates, the signals of interest often are far slower.

Over the last few years I have upgraded and purchased several scopes with bandwidths ranging up to 500 Mhz and in several cases 4 channels.

I seldom have needed bandwidths exceeding 50 MHz.  I constantly use one channel.  Frequently use two channels.  And infrequently use the other two channels.  And out of that stack of Tektronics, LeCroy, Rigol and other scopes the one I use most frequently is the Rigol 1054Z.

Against that background I really think that the question boils down to your passion.  If you care enough the only thing that will keep you from buying the most expensive scope you can afford is the possibility that there is some other piece of test gear (or software) that you could buy by economizing on the scope.  There are tons of interesting and useful gear that can be purchased for the difference in the two scopes you reference.  A signal generator.  A microVNA.  A low end logic analyzer.  A PROM programmer.  A counter.  A voltage reference.  The list goes on and on.  If you shop carefully and go for low end capabilities you can get two or three items from the list for the price difference.

Only you can evaluate how you weigh those opportunities.  In my case, when finances were tight the answer was more types of test gear rather than a higher quality of one type.
« Last Edit: June 19, 2020, 04:35:26 pm by CatalinaWOW »
 

Offline rstofer

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I would like to understand:
- for my use, is not sufficient 2 channel?
There is a tendency to think that more channels are better - and they are.  OTOH, for MANY years, two channels were the limit, only very specialized scopes had 4 channels.  My Tek 485 (350 MHz) scope only has two channels.  I bought the 4 channel Rigol specifically for channels, not bandwidth.  I thought troubleshooting SPI (including decoding) made it worthwhile.
If there is a constraint on cost then something, perhaps channels, has to be reduced.  Money makes the choices here.  200 MHz, 2 channels versus 100 MHz 4 channels is a tough decision (in my view).

Quote
-for my budget, the bandwidth range is 50 to 200 max mhz... with 200 mhz I have many more possibilities (compared to 100mhz?)
 For example the microprocessors in my amplifier work a 20mhz..
Every one of these starter scope threads devolves into rise-time versus bandwidth but since they are tied by a constant, they are equivalent and the specs will show that.  RiseTime = 0.35 / Bandwidth  Bandwidth in GHz and risetime in ns.

https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=9817

The real question is how fast does the rise time need to be to accurately display a square wave rising edge.  But it can be turned around, how many harmonics of the fundamental frequency need to pass through the front end to display a reasonable representation.  Maybe 5?  7?  9?  It depends on how you expect the rising edge to be displayed.  So, with a 100 MHz scope and a desire to display at least the 9th harmonic, you better limit your square wave to 100/9 or around 11 MHz.  The degenerate case of a 100 MHz square wave and a 100 MHz scope is where the square wave looks like a sine wave.  Of course, if the 5th harmonic is good enough, the 100 MHz scope could display a 20 MHz signal.

There really is no substitute for bandwidth.  Since I had bandwidth covered with the Tek 485, I was free to buy the Rigol for the channels.  It is adequate for everything I do because I seldom deal with signals over about 20 MHz outside of FPGAs.

http://www.sigcon.com/Pubs/edn/TaketheFifth.htm

Quote
I want to start playing with the oscilloscope from the simplest things, your buying advice is very useful

Pick any of the scopes on your list and see how much they sell for on eBay as used equipment.  Subtract that from the  new cost and that is your cost of ownership for some period of time.  When (if) you outgrow the scope, sell it on eBay and buy something better.

As I said above, choosing between fewer channels and more bandwidth versus more channels and less bandwidth is tough.  That's why my next scope will probably be the SDS1104X-E because I can get 4 channels and 200 MHz.  I'm not quite there yet.
 

Offline CharlotteSwiss

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thank you all, I'm working now, tonight I update my (confused) ideas here on the forum...
 ^-^
Charlotte
 

Online tggzzz

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The real question is how fast does the rise time need to be to accurately display a square wave rising edge.  But it can be turned around, how many harmonics of the fundamental frequency need to pass through the front end to display a reasonable representation.  Maybe 5?  7?  9?  It depends on how you expect the rising edge to be displayed.  So, with a 100 MHz scope and a desire to display at least the 9th harmonic, you better limit your square wave to 100/9 or around 11 MHz.  The degenerate case of a 100 MHz square wave and a 100 MHz scope is where the square wave looks like a sine wave.  Of course, if the 5th harmonic is good enough, the 100 MHz scope could display a 20 MHz signal.

So you have two signals, a strobe and a chip select (ignore the data!). They are both 1Hz signals. In order to assure correct operation, what bandwidth is reqiured? 5Hz? 11Hz?

But you know the answer because you then go on to say...

Quote
There really is no substitute for bandwidth.  Since I had bandwidth covered with the Tek 485, I was free to buy the Rigol for the channels.  It is adequate for everything I do because I seldom deal with signals over about 20 MHz outside of FPGAs.

All the signals I've seen from FPGAs have significant energy >>20MHz.
There are lies, damned lies, statistics - and ADC/DAC specs.
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Online retrolefty

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Charlotte;

 Trust me if you are as passionate about the electronics hobby as you claim then trust me, your first scope will not be your last scope. I would just buy a popular starter scope (check ebay for number of listings per model so easy to sell) and learn how to use it.

 

Offline james_s

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This has been discussed to death. Gender is irrelevant, I can think of no reason to recommend a different scope for a woman than I would for a man, or somebody who is non-binary or whatever.

Anyway ask 10 people what scope to get and you'll likely get 10 different answers. The Rigol and Siglent models are some of the most popular in the hobbyist community. A friend of mine recently picked up a DS1054Z after I suggested it and he's been raving about it. Previously he had an old Tek 465B analog scope which was a fantastic instrument in its day but I can't think of a reason to recommend one to someone now other than nostalgia or if they need XY mode.
 
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Offline rstofer

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All the signals I've seen from FPGAs have significant energy >>20MHz.
  I imagine it is going to depend on the projects.  I do go about 100 MHz when talking to SRAM but that is usually pretty straight forward and usually on a factory board so known to work. 

SPI has other considerations like the relationship between CS' and the first edge of the clock, CS' going high at the end of the transaction (be certain the last bit has shifted out), 4 different configurations of idle clock state and active clock edge but these are, in my case, under 20 MHz or so.  The big concern is SPI on an FPGA which I coded.  Using SPI on a uC is pretty straight forward except for waiting on the last shift before raising CS'.

I would like to see all 4 signals over the entire transaction.

I'll concede that rise time is the important spec but in every datasheet I have viewed, the scope is rated in bandwidth but the .35 relationship holds.  It's like some kind of universal constant among the manufacturers.  There is some math behind it but I'm not overly interested.

The 100 MHz scope will have a risetime of 3.5 ns almost universally.  So, which came first, rise time or bandwidth?  Actually, the relationship only works when the system can be modeled as a 1st order low pass filter.  Good enough for most purposes.


 

Offline ejeffrey

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I definitely would try to stretch for a 4 channel scope if you are going to do digital / microcontroller projects.  2 channel is fine for a lot of analog electronics.  But 4 channels is enough to show a SPI bus (clock, data, chip select) with one channel left for monitoring whatever sensor or trigger you care about.  That is one specific example, but the basic idea is that in digital electronics you often want to correlate multiple signals happening at the same time.

It isn't necessary of course: the best scope is the one you have.  But if you are deciding between bandwidth and channels at the same price point I would pick more channels almost every time -- lets say choosing between 2 ch 100 MHz and 4 ch 50 MHz.  If you are going to work with high speed FPGAs then you want both bandwidth and channels :)

Also my personal recommendation is not to worry about buying used -- if you are buying a reasonably modern digital scope in working order.  They aren't really like cars where you expect an older one to have higher maintenance costs.  If it works when you plug it in, it is likely to work as long as you need it.  There is always the risk on eBay that you get a DoA, so for your first scope I would recommend buying one that is marketed as fully working with probes included and with a return policy.  That said: if you insist on a lightly used working scope with accessories and a return policy and then include shipping you may or may not get a good deal on a used scope in this case since new ones can be so inexpensive.

A used analog CRO can be really cheap and is a great learning experience, but I wouldn't recommend it as your first or only scope unless it is all you can get.
 

Offline james_s

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The only reason I'd ever recommend an analog CRO as a first or only scope is if it's really cheap, indeed they can sometimes be had for free, I've been given at least a couple of them and given away as many. I also had one as my only scope for quite a few years, an old analog scope is infinitely better than no scope at all.

I think the discussions surrounding bandwidth and risetime are counterproductive for a beginner, it comes up almost every time and it often results in paralysis by indecision. A 10 GHz scope will show you a more accurate representation of the signal than a 1GHz scope which will show a more accurate representation than a 100MHz scope and so on. More bandwidth is ALWAYS better, but bandwidth is expensive. Over 100MHz the price starts to rise, over 200MHz it starts to rise a lot faster, over 300 MHz the price curve starts to go vertical. Even after getting a 1GHz scope I still often used a 100MHz DSO because the one I had was so much smaller and lighter than the GHz boatanchor on my bench. It wasn't as good but I rarely found it inadequate for microcontroller and FPGA projects, I rarely care about the rise time, only the general characteristics and relationship to other signals.

Keep in mind that many lower bandwidth scopes like the 50MHz DS1054Z can be easily unlocked to 100MHz so many people buy the lower end models and upgrade them.
 

Online tggzzz

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All the signals I've seen from FPGAs have significant energy >>20MHz.
  I imagine it is going to depend on the projects.  I do go about 100 MHz when talking to SRAM but that is usually pretty straight forward and usually on a factory board so known to work. 

You can get a sine wave out of an FPGA output? How so?

Quote
SPI has other considerations like the relationship between CS' and the first edge of the clock, CS' going high at the end of the transaction (be certain the last bit has shifted out), 4 different configurations of idle clock state and active clock edge but these are, in my case, under 20 MHz or so.  The big concern is SPI on an FPGA which I coded.  Using SPI on a uC is pretty straight forward except for waiting on the last shift before raising CS'.

So on a strobe + select output that only operates once per second (i.e, 1Hz) you only need to be able to see 11Hz? 9Hz?

I think not.

Period and fundamental frequency are completely and utterly irrelevant with digital signals

Quote
I would like to see all 4 signals over the entire transaction.

I'll concede that rise time is the important spec but in every datasheet I have viewed, the scope is rated in bandwidth but the .35 relationship holds.  It's like some kind of universal constant among the manufacturers.  There is some math behind it but I'm not overly interested.

The 100 MHz scope will have a risetime of 3.5 ns almost universally.  So, which came first, rise time or bandwidth?  Actually, the relationship only works when the system can be modeled as a 1st order low pass filter.  Good enough for most purposes.

Which came first, frequency domain or time domain? Neither, since they are mutual duals.

What does matter is not to refer to square wave frequency/period and harmonics, since practically it is completely irrelevant and it unnecessarily confuses beginners (and under-educated experienced people).
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 Adrian_Arg.

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I am just like your, fan of electronics and arduino, esp32 etc, with the Rigol ds1054z, released and a FY6900, I am so far more than satisfied.   :clap:

in spanish
Yo soy igual que tu, aficionado a la electronica y arduino, esp32 etc, con el Rigol ds1054z, liberado y un FY6900, estoy por ahora mas que sastifecho.
 

Offline rstofer

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I think the discussions surrounding bandwidth and risetime are counterproductive for a beginner, it comes up almost every time and it often results in paralysis by indecision.
Except for the part where they want to view a 20 MHz square wave on a 20 MHz scope.

Everybody knows the -3dB bandwidth of their scope, it is on the front panel somewhere (usually).  Rise time?  Well, that requires a dive into the specifications.  Or a calculator...

We could try to change the industry into printing the rise time on the front panel but I wouldn't count on it happening any time soon.

We use an enormous number of pixels on this subject and the responses never change.  It really should be a sticky and EVERY response should be a link back to the sticky.

For the casual user, the DS1054Z is more than enough for a very long time.  The fact that so many users around here have that scope is sufficient reason to believe it is capable of meeting diverse needs over a range of users.  Yes, I would go for the SDS1104X-E but that's because I'm not all that price sensitive for an expenditure of that magnitude.  I'm not in the market for anything beyond the 1104's capability, my projects don't warrant anything more sophisticated.  There are examples of users around here needing far more sophisticated equipment but they generally know about the need and know full well what equipment to buy.

Can lesser scopes do the job?  Certainly!  But it soon becomes a race to the bottom and the result is a scope that meets some current minimum expectation but isn't capable of growing with experience.  Heck, I got along with a 10 MHz scope for a decade or more.  It worked well for what I was doing at the time.  8080s and TTL just didn't run all that fast..  It would be totally useless for my current projects.
 

Offline Electro Fan

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I would like to understand:
- for my use, is not sufficient 2 channel?
There is a tendency to think that more channels are better - and they are.  OTOH, for MANY years, two channels were the limit, only very specialized scopes had 4 channels.  My Tek 485 (350 MHz) scope only has two channels.  I bought the 4 channel Rigol specifically for channels, not bandwidth.  I thought troubleshooting SPI (including decoding) made it worthwhile.
If there is a constraint on cost then something, perhaps channels, has to be reduced.  Money makes the choices here.  200 MHz, 2 channels versus 100 MHz 4 channels is a tough decision (in my view).

Quote
-for my budget, the bandwidth range is 50 to 200 max mhz... with 200 mhz I have many more possibilities (compared to 100mhz?)
 For example the microprocessors in my amplifier work a 20mhz..
Every one of these starter scope threads devolves into rise-time versus bandwidth but since they are tied by a constant, they are equivalent and the specs will show that.  RiseTime = 0.35 / Bandwidth  Bandwidth in GHz and risetime in ns.

https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=9817

The real question is how fast does the rise time need to be to accurately display a square wave rising edge.  But it can be turned around, how many harmonics of the fundamental frequency need to pass through the front end to display a reasonable representation.  Maybe 5?  7?  9?  It depends on how you expect the rising edge to be displayed.  So, with a 100 MHz scope and a desire to display at least the 9th harmonic, you better limit your square wave to 100/9 or around 11 MHz.  The degenerate case of a 100 MHz square wave and a 100 MHz scope is where the square wave looks like a sine wave.  Of course, if the 5th harmonic is good enough, the 100 MHz scope could display a 20 MHz signal.

There really is no substitute for bandwidth.  Since I had bandwidth covered with the Tek 485, I was free to buy the Rigol for the channels.  It is adequate for everything I do because I seldom deal with signals over about 20 MHz outside of FPGAs.

http://www.sigcon.com/Pubs/edn/TaketheFifth.htm

Quote
I want to start playing with the oscilloscope from the simplest things, your buying advice is very useful

Pick any of the scopes on your list and see how much they sell for on eBay as used equipment.  Subtract that from the  new cost and that is your cost of ownership for some period of time.  When (if) you outgrow the scope, sell it on eBay and buy something better.

As I said above, choosing between fewer channels and more bandwidth versus more channels and less bandwidth is tough.  That's why my next scope will probably be the SDS1104X-E because I can get 4 channels and 200 MHz.  I'm not quite there yet.

To the OP,

There is a bunch of good advice being posted in the replies to the thread you have started, one of which is retrolefty's comment that "if you are as passionate about the electronics hobby as you claim then trust me, your first scope will not be your last scope" - which also ties a little bit to rstofer's 3rd section (see above). 

fwiw, as a person who has over a period of nearly 20 years accumulated 4 scopes (three analog and one digital including scopes 2-4 since I found this site - look up "TEA"), I would say that the smart first choice for most first time scope users would be a digital scope.  Certainly for some situations and use cases a good case can be made for an analog scope, but these cases are more likely to be exceptions rather than the typically applicable rule.  Currently, depending on your budget I'd say you could choose between the Rigol 1054Z and the Siglent 1104X-E.  Either will give you a good useful life and will have some residual value if you need to sell it to fund something else.

rstofer,

Your posts are consistently good but I think this one might be approaching or reaching "sticky" quality - some version of it might deserve to be stuck up above under a "FAQ" that addresses how to think about the tradeoffs between 2 or 4 channels vs more bandwidth.  Each of your 3 sections is very good, especially your second section (about how much bandwidth is needed, rise times, harmonics, and "degenerate" square waves), and the third section makes a good practical suggestion too (about taking into consideration some potential residual value).  I think you have just about nailed the refinement on how to address these tradeoffs.  Nice work  :-+
 

Offline Electro Fan

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<snip>

What does matter is not to refer to square wave frequency/period and harmonics, since practically it is completely irrelevant and it unnecessarily confuses beginners (and under-educated experienced people).

Ok, I just saw tggzzz's comment and I think there is some validity here too - so if I can have my cake (rstofer's comments) and eat it too (tggzzz's comments) it could be that although it might not be totally irrelevant the discussion of harmonics, square waves that look like sine waves, etc. might be too much for most first time scope users to digest.  As tggzzz says some first time users might find it confusing or possibly irrelevant - but on the other hand some first time users might have the wherewithal and interest to see where these discussions lead in terms of making purchase decisions. 

Owning and using a scope can be a lot of fun and a great educational experience, but shopping for the right scope and learning the criteria for selecting a scope can also be educational and often a fun part of the process.

If there is a common theme we see in first time user questions it's that many are not totally sure what they are going to do with the scope, and many are pretty sure they will discover other uses, and they sense that if they could better anticipate what's over the horizon, they might then select a different scope (than what is dictated by initial uses).  So, I think it's good for the more experienced users to layout the path with first fundamentals first but also with a bit of stretch to touch upon next level considerations - and then the users can eat as much as their appetite dictates.  Like a lot of stuff, it's a balancing act.  The good news is this site exists for both "students" to learn and for "teachers" to teach - and as long as the students are willing to keep framing questions there are many teachers here who are devoted to teaching.  So in my view, while it's good for the teachers to try to teach relevant "on-level" material it's especially incumbent on the students (at every level) to keep framing questions and then if the shoe fits.... cool.
 

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Owning and using a scope can be a lot of fun and a great educational experience, but shopping for the right scope and learning the criteria for selecting a scope can also be educational and often a fun part of the process.

If there is a common theme we see in first time user questions it's that many are not totally sure what they are going to do with the scope, and many are pretty sure they will discover other uses, and they sense that if they could better anticipate what's over the horizon, they might then select a different scope (than what is dictated by initial uses).  So, I think it's good for the more experienced users to layout the path with first fundamentals first but also with a bit of stretch to touch upon next level considerations - and then the users can eat as much as their appetite dictates.  Like a lot of stuff, it's a balancing act.  The good news is this site exists for both "students" to learn and for "teachers" to teach - and as long as the students are willing to keep framing questions there are many teachers here who are devoted to teaching.  So in my view, while it's good for the teachers to try to teach relevant "on-level" material it's especially incumbent on the students (at every level) to keep framing questions and then if the shoe fits.... cool.

That's why I wrote...

"More seriously, any working scope is better than none. You will pay to gain experience with your money and your time. There is an argument that experience with a cheap working scope will enable you to understand what you actually need."

and added the hints about using a scope safely!


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
 


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