EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: nsummy on April 30, 2024, 06:20:12 pm
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I hate to add another oscilloscope thread as I know the info is out there but I am overwhelmed. Reading this stuff almost feels like reading in-depth reviews for tvs and cameras: The people reviewing use all of the capabilities so anything but the high(er) end seems like utter garbage.
I have slowly but surely been getting into electronics in general and more specifically vintage electronics. I'm a beginner but starting to advance to reading service manuals & am now wanting to perform alignments & other test steps in these manuals. Its clear I need to get an oscilloscope to do anything meaningful. I know enough about test equipment & its eye watering prices to know that $300 for a new oscilloscope is "cheap" but I can't help but think there has to be something cheaper that can give basic & accurate measurements. The DHO800 is $330 but I know I do not need all of the capabilities it provides. Looking at used prices on ebay bottom prices for an (old) digital scope seem to be about $200+ and at that point I might as well just spend the extra $100. I see analog scopes recommended but many are sold "for parts" and I think initially I will need a scope that I can trust the readings.
TL;DR Is there anything out there in the $100-$200 range that can provide reliable functionality to do something like aligning an FM receiver or verify an old EICO signal generator is working.
Also for what its worth, my inspiration for this post was reading the thread on the Hanmatek DOS1102 and truly couldn't tell if it was junk or decent enough for my needs: https://www.eevblog.com/forum/testgear/wow (https://www.eevblog.com/forum/testgear/wow)!-$123-hanmatek-dos1102-initial-comments/
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Good enough for FM !!!
https://www.amazon.com/FNIRSI-1014D-Dual-Channel-Oscilloscope-Generator-Bandwidth/dp/B097T5NRTZ/ref=sr_1_18?crid=3HIPUJHWE3Y4A&dib=eyJ2IjoiMSJ9.WoZDHjN6HecMkQMHtx4S4sW1q54hO8cokgRLezwcUJzKC3I5bTgBjP0oi02DTj5E0Ufxum6arVqBBi7TGyDoZyMhLPXJQLIJVDCxvcJXY6a8HSwBSaZL_SL8ZAp_1l0n32cBPmXeZoIfDfMkLcrQs8J80L81GF5a1i32x01stBGrQD9HnjI9UBnpbmNWl_BjYK9qR2JF1gO4fvhivugpLDDNWM8odwKIPv3NpMLvG_s.pyC4dsWOmaTX-ndDARF0QITWnx4HoNkE7D8L5AL_umA&dib_tag=se&keywords=oscilloscope+50MHz&qid=1714503049&sprefix=oscilloscope+50mhz%2Caps%2C152&sr=8-18 (https://www.amazon.com/FNIRSI-1014D-Dual-Channel-Oscilloscope-Generator-Bandwidth/dp/B097T5NRTZ/ref=sr_1_18?crid=3HIPUJHWE3Y4A&dib=eyJ2IjoiMSJ9.WoZDHjN6HecMkQMHtx4S4sW1q54hO8cokgRLezwcUJzKC3I5bTgBjP0oi02DTj5E0Ufxum6arVqBBi7TGyDoZyMhLPXJQLIJVDCxvcJXY6a8HSwBSaZL_SL8ZAp_1l0n32cBPmXeZoIfDfMkLcrQs8J80L81GF5a1i32x01stBGrQD9HnjI9UBnpbmNWl_BjYK9qR2JF1gO4fvhivugpLDDNWM8odwKIPv3NpMLvG_s.pyC4dsWOmaTX-ndDARF0QITWnx4HoNkE7D8L5AL_umA&dib_tag=se&keywords=oscilloscope+50MHz&qid=1714503049&sprefix=oscilloscope+50mhz%2Caps%2C152&sr=8-18)
and still good enough for FM.....
https://www.amazon.com/FNIRSI-2C23T-Oscilloscope-Multimeter-Generator/dp/B0CMT5WMFY/ref=sr_1_3?crid=1YD78RCECO18B&dib=eyJ2IjoiMSJ9.a3LJUX28uy8JHXmLAKVRuEgSueVm_z-a_Gm2AZzQqdOgrNiU_ClbEanT5REteR0l-VQcnzPY4pf2Hj_fHFk-5L-iQ02K_NN1tHXw0XOyOJfN2ij0nIk44HTN_qe4CH5Luc4Bv0l_6h4C5dRP8u6xiJV7Y-zTAV2AKi-NFpInUWCrID9cQFI07cJBgc632EXKFTyd7tjmmPZR1PmaoeThV8wcGibM0ch8e6ept9-8Os0.jIm5XfP85Eu1tYrFuEcTQ41moZCbC9qi72s_wkEnFS0&dib_tag=se&keywords=FNIRSI&qid=1714503136&sprefix=fnirsi%2Caps%2C179&sr=8-3 (https://www.amazon.com/FNIRSI-2C23T-Oscilloscope-Multimeter-Generator/dp/B0CMT5WMFY/ref=sr_1_3?crid=1YD78RCECO18B&dib=eyJ2IjoiMSJ9.a3LJUX28uy8JHXmLAKVRuEgSueVm_z-a_Gm2AZzQqdOgrNiU_ClbEanT5REteR0l-VQcnzPY4pf2Hj_fHFk-5L-iQ02K_NN1tHXw0XOyOJfN2ij0nIk44HTN_qe4CH5Luc4Bv0l_6h4C5dRP8u6xiJV7Y-zTAV2AKi-NFpInUWCrID9cQFI07cJBgc632EXKFTyd7tjmmPZR1PmaoeThV8wcGibM0ch8e6ept9-8Os0.jIm5XfP85Eu1tYrFuEcTQ41moZCbC9qi72s_wkEnFS0&dib_tag=se&keywords=FNIRSI&qid=1714503136&sprefix=fnirsi%2Caps%2C179&sr=8-3)
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Go to a local Hamfest and see if you can find one that works. I have seen nice scopes for under $100 including a Tek 475 (200 MHz) recently.
https://www.arrl.org/hamfests/search (https://www.arrl.org/hamfests/search)
Just put in your state.
Oh, make sure your probes match the input capacitance of your scope, plenty of good cheap probes from China.
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The FNIRSI 1014D is pretty much the worst benchtop scope.
In comparison, a Hantek DSO2C10 (https://www.aliexpress.com/item/1005004787775801.html) is a serious measuring instrument (with some shortcomings of course) for about the same price.
Unfortunately, not much is known about the cheaper models from Owon, Hanmatek, Vevor and what they are all called.
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I hate to add another oscilloscope thread as I know the info is out there but I am overwhelmed. Reading this stuff almost feels like reading in-depth reviews for tvs and cameras: The people reviewing use all of the capabilities so anything but the high(er) end seems like utter garbage.
I have slowly but surely been getting into electronics in general and more specifically vintage electronics. I'm a beginner but starting to advance to reading service manuals & am now wanting to perform alignments & other test steps in these manuals. Its clear I need to get an oscilloscope to do anything meaningful.
We deal with all this most days.
For sure you are partially blind without a scope but for so little cost today an instrument is available that can serve you for many years and particularly as your skill and knowledge grows.
While the feature set in modern scopes seems daunting it soon becomes familiar and you will in due course use it.
You don't need to invest lots but best advice is to future proof your purchase with functionality you can grow into.
I think back to my first DSO (a Tek TDS2012B) and even that 2nd hand price vs what you can get now for the same money (new) and the extraordinary feature set offered I'm sad I did not back then have one of the entry level DSO's available today.
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TL;DR Is there anything out there in the $100-$200 range that can provide reliable functionality to do something like aligning an FM receiver or verify an old EICO signal generator is working.
Consider a simple working analogue scope for simple tasks like those. Extra benefit: simpler, so the learning curve is shorter; digitizing scopes' complexity can be overwhelming for a beginner.
A reasonable price is $1/MHz, so a 20MHz scope should be very cheap - my local hackspace has so many they are giving them to members to make space! Think of it as a disposable learning tool; afterwards you will have a better idea of what you need.
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Consider a simple working analogue scope for simple tasks like those. Extra benefit: simpler, so the learning curve is shorter; digitizing scopes' complexity can be overwhelming for a beginner.
Shhh..... you'll wake up the anti-analog guard
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TL;DR Is there anything out there in the $100-$200 range that can provide reliable functionality to do something like aligning an FM receiver or verify an old EICO signal generator is working.
The problem is that in this very competitive market and at the $300-500 price points every nickel you spend gets you a LOT more. I see very little point in buying anything less than a Siglent SDS804X HD, but if you really need to save $100 perhaps the SDS802X HD 2-channel will suffice.
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I hate to add another oscilloscope thread as I know the info is out there but I am overwhelmed. Reading this stuff almost feels like reading in-depth reviews for tvs and cameras: The people reviewing use all of the capabilities so anything but the high(er) end seems like utter garbage.
I think I have paid about the same for my camera and lenses as I paid for my oscilloscopes and probes - one consumer difference is that my camera has plenty of YouTube reviews and interest. It does feel like though you're often left to your own devices with test equipment. :palm:
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I agree with the last two posts in particular. I have been learning only for 6 months, but for $350 I bought a brand new Siglent 4 channel that I upgraded for free to 200 mHz (these scopes come with the features of their upgraded brethern, just locked. But there are many sources explaining how to unlock those features, and it does not effect your warranty).
I also own a 100mHz analog (2 but only my wife is counting). You can buy the analogs for $100 delivered. These are sold as "parts only" but if you restrict yourself to the major ebay dealers you have 30 day and usually free returns. I have no idea why the "parts only"; certainly has no impact on eBay buyer protection. Maybe to limit liability for damages caused by the user?? I don't understand.
The new digital scopes are overwhelming. I cannot see me using the Siglent's full potential for a long time. But people here will help you figure out how to do what you want.
I like the analogs because the selections are all right there, no menus to drill down through. On the other hand, you will appreciate the cursors and the measurement displays on the digitals.
As was mentioned, there is a cost to education. You cannot go wrong with a Siglent, but if you want to get your feet wet, then look at a used analog. If nothing else, you can darken the room and watch the pretty lights.
If you go with an analog, I highly recommend downloading the service manual for it BEFORE you buy. A lot of user information plus you have the info for making adjustments if they become needed. If you buy a new digital scope, research the brand's reputation for after sales service and firmware upgrades.
I almost bought a scope from the Keysight Used Store. But the runaround and hoops raised concerns about after sales service. Glad they chased me away.
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Extra benefit: simpler, so the learning curve is shorter; digitizing scopes' complexity can be overwhelming for a beginner.
People here keep talking as if a beginner is somehow mentally handicapped. ;)
I'm a beginner and it's exciting for me to discover all the possibilities of my DSO.
I can use "Auto Set" and Edge Trigger on the DSO if I want to keep things simple.
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For ages I had a nice second-hand Hitachi storage 'scope, and as far as I was concerned it was awesome. Easy to use, I got a lot of value out of it.
Even though I eventually had several other more modern 'scopes, I enjoyed using that one in particular. I gave it away about 6-7 years ago to someone who needed it, so it's possible to get old scopes for free or next-to-nothing. Not only is it ideal for beginners, I would also put it this way: if I still had it, I would still use it, since it was a delight to use.
(Attached image is from ebay, since I don't have a photo of mine any more, but it was the same model).
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Thank you for all of the replies. I found this on ebay and was wondering what everyone thought? https://www.ebay.com/itm/404930733283?epid=0&itmmeta=01HWR6P31AV2TC4YQ9CKW2YQ85&hash=item5e47c0a4e3:g:ou0AAOSwmQFmISQ2 (https://www.ebay.com/itm/404930733283?epid=0&itmmeta=01HWR6P31AV2TC4YQ9CKW2YQ85&hash=item5e47c0a4e3:g:ou0AAOSwmQFmISQ2)
Its an 54645A 100MHz-200 MSa/s. I have read the sampling rate should be 5x the MHZ. Would this be a bad buy? The price is certainly right.
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Go for it!
Odds are you'll never need more than 20...40 MHz bandwidth anyway.
Best starter 'scope I've seen.
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Looks pretty nice to me....actually looks hardly used at all. I do not see any probes, perhaps ask seller if they are included? Otherwise they are not expensive.
Shipping is another expense.....Free!Let's hope he packs it well..
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I have read the sampling rate should be 5x the MHZ.
The only important signal parameter is the transition time, since that determines the signal's bandwidth. FFI see https://entertaininghacks.wordpress.com/2018/05/08/digital-signal-integrity-and-bandwidth-signals-risetime-is-important-period-is-irrelevant/
In order to reconstruct the signal from the samples, there need to be at least two samples per period, e.g. a 10MHz signal needs at least 20MS/s. In practical scopes there needs to be at least 2.5 samples per period, i.e. 25MS/s for a 10MHz signal. For convenience, many scopes have much higher sampling rates (e.g. 10 samples per period) - but that does not change the signal's bandwidth-transition time relationship.
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I hate to add another oscilloscope thread as I know the info is out there but I am overwhelmed. Reading this stuff almost feels like reading in-depth reviews for tvs and cameras: The people reviewing use all of the capabilities so anything but the high(er) end seems like utter garbage.
Given that, until fairly recently, the likely most-recommended scope in the world was the Rigol DS1054Z, I don't think it’s at all fair to characterize the reviews like that.
…Its clear I need to get an oscilloscope to do anything meaningful. I know enough about test equipment & its eye watering prices to know that $300 for a new oscilloscope is "cheap" but I can't help but think there has to be something cheaper that can give basic & accurate measurements. The DHO800 is $330 but I know I do not need all of the capabilities it provides. Looking at used prices on ebay bottom prices for an (old) digital scope seem to be about $200+ and at that point I might as well just spend the extra $100. I see analog scopes recommended but many are sold "for parts" and I think initially I will need a scope that I can trust the readings.
TL;DR Is there anything out there in the $100-$200 range that can provide reliable functionality to do something like aligning an FM receiver or verify an old EICO signal generator is working.
If you’re willing to spend $200, just spend the $330-400 and get a new Rigol or Siglent. I think you’ll be happier in the long run. Early digital scopes represent one of the least-attractive options possible, because they have serious limitations (foremost among them: very small memory depth) without getting you any of the advantages of an analog scope (absolute responsiveness, smooth display).
The aforementioned Rigol was the first scope I ever owned (and the first I ever used), and it certainly wasn’t overwhelming, and I didn’t know anything about them at the time. But now I do, and a lot of the things I suspect you’re dismissing as unneeded bells and whistles are actually really useful. You’ll grow into them.
The one thing that digital scopes really excel at, and precisely where deep memory is super useful, is single-shot capture, and the ability to zoom in after capture to look at details. Analog scopes can’t do this at all (ignoring the tiny handful of spectacularly expensive and rare analog storage scopes that were made for a while), and old digital scopes do it very poorly by today's standards. Another is triggering, where digital scopes can do more complex triggering that is really useful in practice.
And super cheap (under $300) new digital scopes today fall into a similar “uncanny valley” as old digital scopes: they’re mostly so bad as to be functionally useless. Any tool, whether basic or advanced, needs to be competent at whatever it’s meant to do. The super cheap scopes often fail at even basic functionality, like reliably triggering on a simple periodic signal. An untrustworthy tool is often worse than none at all.
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Its an 54645A 100MHz-200 MSa/s. I have read the sampling rate should be 5x the MHZ. Would this be a bad buy? The price is certainly right.
This is the sort of thing I'd typically advise you to avoid--an early non-hybrid DSO--because of both reliability and capability problems. However, I'd make an exception for this one because it looks like it is in good shape and works, IIRC it is well documented ( https://xdevs.com/doc/HP_Agilent_Keysight/HP%2054645A,%2054645D%20User%20&%20Service.pdf ) and it will do the things you need it to reasonably well.
It has 1Mpts memory and Megazoom, so although it isn't the 10 to 200Mpts you might get with a modern scope, it is enough for many frames of capture in most cases. The sampling rate only allows for a 50MHz bandwidth for single-shot captures. For repetitive waveforms only it uses Equivalent Time Sampling (ETS) to acquire a waveform over multiple captures that are just a bit offset from each other. If you only want to spend $129, then this is going to be a better idea than some new steaming pile of junk that doesn't, never did and never will work properly.
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Given that, until fairly recently, the likely most-recommended scope in the world was the Rigol DS1054Z...
For the hobbyist market :)
Looking at used prices on ebay bottom prices for an (old) digital scope seem to be about $200+ and at that point I might as well just spend the extra $100. I see analog scopes recommended but many are sold "for parts" and I think initially I will need a scope that I can trust the readings.
I would definitely spend the extra $100 :). Speaking as a hobbyist, I would gladly trade any of my older hobbyist DSOs plus $100 to get a current-manufacture hobbyist DSO.
And although I know I'm opening a can of worms (so to speak) by saying this: I would not buy a used (and nowadays they are all "used") analog scope as your only oscilloscope. I really like analog scopes, but a (new) modern hobbyist DSO is a much better choice if you can only have one scope.
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I would definitely spend the extra $100 :). Speaking as a hobbyist, I would gladly trade any of my older hobbyist DSOs plus $100 to get a current-manufacture hobbyist DSO.
Me to. It's the difference between something that is probably adequate now but you will find lacking in one or two years, versus having a decent instrument for the next 10+ years. If you think it's too much now, then wait a few months or half a year if you can to save up some money. Consider that if you can use it for 10 years, even an EUR400 scope will just be EUR 40 per year.
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I know many here will disagree, but I would prefer my Hantek DSO2000, which I also paid $130 for, over this 54645A, not for some “fuzzy” reasons like “I've heard it can't trigger properly" or "pile of junk" but for hard facts.
1. The 54645A is probably 20 years old and you don't know what condition it's in.
2. it is approx. 32 cm deep (excluding handle ;) ). I have no space for it.
3. it is heavy.
4. it consumes 200-300 W, the Hantek less than 15W (no fan).
5. it has no SCPI, so I can't extend the functionality with scripts.
6. it has no FFT
7. it has no AWG (with AM, FM, burst...).
8. the Hantek has many more trigger variants plus pass/fail.
9. it can't save anything to USB stick
10. etc. etc.
Other people have other priorities. Everyone has to decide for themselves.
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My 2 cents provided w/o further evidence:
- Most cheap/used scopes will probably do what you need. I had a Rigol DS1102E for a long time and just replaced it recently – because I wanted something better/cooler, not because I really needed it.
- Stay a way from non-brands like FNIRSI. But anything from brands popular with hobbyists, like Rigol or Siglent as well as some less highly regarded ones such as Owon or Hantek will most likely serve you well.
- While old (often analog) scopes are cool, and I very much enjoy owning one, I would not recommend getting one as your first scope because you need to be able to assess if they are in good working condition and fix them if necessary. But they make excellent second scopes (or repair projects) once you have a known-good one to diagnose them with
- It's ok to have a bunch of features you don't understand or need – I certainly don't understand 100% of what my latest toy (SDS2104X Plus) is capable of.
- As a hobbyist, it is also ok to go feature overkill if you get pleasure out of that... (I do)
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I bought 2 scopes and then I bought a proper scope.
Don't be like me, go for the proper scope first.
Owon 20Mhz USB isolated scope. $100 Starts to show bandwidth issues around 5-10Mhz. Horrible PC based software.
FNIRSI 1014D 100Mhz scope. $150 I used it for 1 month and it was the thing that made me take 6 month interest free credit and buy:
Siglent SDS-1104-XE $500 ish.
The FNIRSI is first nerfed by the god awful software. The screen can't even render waveforms even if the front end can sample them. The front end gets to about 20Mhz with -3db attentuation. Above 50Mhz is useless and the waveform rendering packs in.
Both the OWON and the FNIRSI I keep on a shelf. They have purpose. They are both isolated and both can run on battery power making them "mobile".
If I want to scope the mains or do something "sketchy" with a scope, I know I'm not using the Siglent... lets say.
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I know many here will disagree, but I would prefer my Hantek DSO2000, which I also paid $130 for, over this 54645A, not for some “fuzzy” reasons like “I've heard it can't trigger properly" or "pile of junk" but for hard facts.
1. The 54645A is probably 20 years old and you don't know what condition it's in.
2. it is approx. 32 cm deep (excluding handle ;) ). I have no space for it.
3. it is heavy.
4. it consumes 200-300 W, the Hantek less than 15W (no fan).
5. it has no SCPI, so I can't extend the functionality with scripts.
6. it has no FFT
7. it has no AWG (with AM, FM, burst...).
8. the Hantek has many more trigger variants plus pass/fail.
9. it can't save anything to USB stick
10. etc. etc.
Other people have other priorities. Everyone has to decide for themselves.
Precisely.
One size doesn't fit all.
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You could buy an analogue scope for $40 or more. You'd need to be satisfied it worked and was more or less in calibration. You might find that's all you need. It could develop problems you wouldn't want to fix, because they are all old now. Analogue scopes are always nice to have around.
Other than that you mentioned a DHO800 for $330. If you've got the $330 I think you should go for that. It may be more than you need, but something that can comfortably do the job is always good. It's amazing the way requirements expand.
I'd avoid hobbyist DSOs apart from Rigol and Siglent. I get the impression that they are not very well supported with firmware updates etc. I'm sure there are Owon, Hantek, Fnirsi owners who would disagree, but that's the way I see it.
I think you'd find the 54645A a PITA. Too big, too heavy and not as capable as modern DSOs plus problems if it goes wrong.
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The FNIRSI is first nerfed by the god awful software. The screen can't even render waveforms even if the front end can sample them. The front end gets to about 20Mhz with -3db attentuation. Above 50Mhz is useless and the waveform rendering packs in.
I know that “from above” all junk piles look the same height, :-DD but just so there's no misunderstanding, the Hantek DSO2000 can do things the Fnirsi 1014D can't even dream of.
It's also made on a tight budget of course, but if you can buy it for ~$150, it delivers in my opinion.
For example, as a “100MHz” scope it is capable of measuring 200MHz even in 2-channel mode (@500MSa/s Image 1). I'm not talking about -3dB, but it doesn't show total garbage or wrong frequencies like the Fnirsi would.
Or it can measure the frequency of a sine wave <1mVpp (Image 2). Again, a 1014D definitely can't do that.
It is simply a $130/$150 scope. For this price, it's just good enough. For $300+ there are much better scopes.
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You could buy an analogue scope for $40 or more. You'd need to be satisfied it worked and was more or less in calibration. You might find that's all you need. It could develop problems you wouldn't want to fix, because they are all old now.
And then you would need to buy a modern DSO to troubleshoot your analog scope :)
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You could buy an analogue scope for $40 or more. You'd need to be satisfied it worked and was more or less in calibration. You might find that's all you need. It could develop problems you wouldn't want to fix, because they are all old now.
And then you would need to buy a modern DSO to troubleshoot your analog scope :)
Yup, seems we've both been there and earned the darn T shirt. ;D 8) :-+
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You could buy an analogue scope for $40 or more. You'd need to be satisfied it worked and was more or less in calibration. You might find that's all you need. It could develop problems you wouldn't want to fix, because they are all old now.
And then you would need to buy a modern DSO to troubleshoot your analog scope :)
Actually you wouldn't. You often find you need a scope to fix a scope, but it usually doesn't need to be a very good one.
I think the OP would be best served by spending $330 on the DHO800.
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Mechanicals are many times omitted.
I have around 5x2m room with "road encumberance" to balcony.
5 is fine but 2 is not enough for two chairs.
2 probably could be fine but then it needs completely other furniture.
80cm table is not enough for almost any old style CRO.
Only possibility is to tilt or move it to some direction, my version is face up and under a table with wheels.
Tilting is not so big problem if you don't have classes.
If you always have had your glasses you're different from me, I've had glasses only some years and I've not yet learned to turn my head.
Means also that sight is out of sight in no time, if direction is somewhere else than front of glasses.
It doesn't help that my probe tips are bulky, means that moving a head too much jeopardizes the position of the probe.
Checking old style parallel bus is a good example.
Never tried a hand mirror, could be practical, maybe not.
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You could buy an analogue scope for $40 or more. You'd need to be satisfied it worked and was more or less in calibration. You might find that's all you need. It could develop problems you wouldn't want to fix, because they are all old now.
And then you would need to buy a modern DSO to troubleshoot your analog scope :)
Not necessarily.
Most faults (other than cracked cases/knobs) are electrolytic capacitors (diagnose with voltmeter measuring both DC and AC), and gummed up switched.
The most interesting fault I had was a 465 that was working well, except it was doing a very good impersonation of a torch: it cast a shadow on the opposite wall without the lights being dimmed :) Turned out to be the grid had become disconnected inside the CRT. Worked out the fault had to be inside the CRT (not any of the EHT components) using only a simple voltmeter. Took a lot of time, but it was an interesting puzzle. Not recommended for beginners!
But more realistically, a beginner should only buy working equipment - and that is true for not only old equipment, but also brand new equipment.
Now, what was that about buggy firmware?
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Mechanicals are many times omitted.
I have around 5x2m room with "road encumberance" to balcony.
5 is fine but 2 is not enough for two chairs.
2 probably could be fine but then it needs completely other furniture.
80cm table is not enough for almost any old style CRO.
Only possibility is to tilt or move it to some direction, my version is face up and under a table with wheels.
10m2. That big? I really envy you.
My room is 6.6m2 (2.3*2.9m).
My worktop is a repurposed kitchen worktop with Ikea legs. 62cm deep.
All my scopes fit, e.g. Tek 485, Tek 2465, Tek 1502, HP 1740, Philips 3410, HP/Agilent 53310A, Tek 492, HP 8562A, Tek TDS710, - albeit not all at the same time :)
I really must sell some.
Personally I wouldn't have any equipment that requires wheels; it would be too difficult/dangerous to get them upstairs.
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Not necessarily.
Most faults (other than cracked cases/knobs) are electrolytic capacitors (diagnose with voltmeter measuring both DC and AC), and gummed up switched.
But more realistically, a beginner should only buy working equipment - and that is true for not only old equipment, but also brand new equipment.
Now, what was that about buggy firmware?
There are numerous threads here from new users that have purchased an analog scope and are asking for help repairing it. The apparent success rate has not been high despite a serious effort on their part and the people here attempting ot help. Out of the dozen or so CROs I've repaired (or tried to) recently only one had "bad capacitors" sufficient to actually cause the issues making the scope unusable and even that one had more issues. I've had broken/bad switches, bad solder joints, bad hybrid ICs, damaged CRT, bad flex circuit board, failed transistors, calibration battery failure, etc etc. And those are the ones I have fixed. I still have a few in the queue that need advanced help.
I haven't seen or heard of any firmware issues in products by Rigol/Silent/GW Instek et al that are so severe that a new user would even notice them, let alone be unable to use the DSO. Now if you're talking about Fnirsi or Vevor, well....
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As always,
ignore advice of buying an analog scope.
It's a practical joke many experienced guys play on the poor young players. You can buy an analog scope later for a toy or some niche uses, but it's so much more limited instrument for general purpose design/prototyping/repair work of 2000's so that you have to buy a DSO anyway so better get that one first.
Getting rid of that, usually any modern day DSO, even a fairly cheap Chinese one, will work fine, until you know exactly what the specs mean and need something more specific. The biggest issues in cheap scopes are related to less responsive user interfaces, small bugs etc. These are not showstoppers. The advantage of a cheap unit is that you are not wasting a lot of money for nothing. You will later understand all the specs.
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As a very novice amateur, I agree that if the extra $250 for a spanking new digital scope is not a barrier over the $100 for a used analog in good condition, then the $250 is money well spent.
On the other hand, by choosing my sellers, I have two good 100MHz Kenwood scopes that worked out of the box. I did learn much from adjusting them per the service manuals. Earlier I bought one other scope for $50 that had a weak channel 2. Hoped it was in the preamp, but it is not and since I have 2 others, It is now not even a distraction. Shame, but....
I keep on my bench the Siglent and Kenwood. I like the Siglent because it can easily be put within reach, the Kenwood, not so much. But until I watched the Keysight videos linked toward the end of the post Charlotte started (https://www.youtube.com/playlist?list=PL2XuMA5AwNUznkBE46tcZAF3p5Edxgm-z (https://www.youtube.com/playlist?list=PL2XuMA5AwNUznkBE46tcZAF3p5Edxgm-z)) I was always confused about how to manually set up my Siglent.
While I agree that a new digital scope (especially the new ones out this year) is something you can grow into (as my mother said when it came to shoes and pants), the learning curve is steeper. But the Keysight playlist goes a long way to making the climb easier.
Just my thoughts as a mature (maybe?) learner who is navigating all of this.
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Its an 54645A 100MHz-200 MSa/s. I have read the sampling rate should be 5x the MHZ. Would this be a bad buy? The price is certainly right.
This is the sort of thing I'd typically advise you to avoid--an early non-hybrid DSO--because of both reliability and capability problems. However, I'd make an exception for this one because it looks like it is in good shape and works, IIRC it is well documented ( https://xdevs.com/doc/HP_Agilent_Keysight/HP%2054645A,%2054645D%20User%20&%20Service.pdf ) and it will do the things you need it to reasonably well.
It has 1Mpts memory and Megazoom, so although it isn't the 10 to 200Mpts you might get with a modern scope, it is enough for many frames of capture in most cases. The sampling rate only allows for a 50MHz bandwidth for single-shot captures. For repetitive waveforms only it uses Equivalent Time Sampling (ETS) to acquire a waveform over multiple captures that are just a bit offset from each other. If you only want to spend $129, then this is going to be a better idea than some new steaming pile of junk that doesn't, never did and never will work properly.
I went ahead and bought it. Thank you also Wallace Gasiewicz & Benta and everyone else for the advice. This will probably be a quick stepping stone for me to get my feet wet before I buy a siglent or rigol. I'm a big believer in the "buy once, cry once" philosophy but want to learn on something quick & simple.
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While I agree that a new digital scope (especially the new ones out this year) is something you can grow into (as my mother said when it came to shoes and pants), the learning curve is steeper. But the Keysight playlist goes a long way to making the climb easier.
Just my thoughts as a mature (maybe?) learner who is navigating all of this.
That's a sensible perspective.
Good tutorials play a valuable role in education, and hence are to be welcomed.
There are too many half-baked explanations/tutorials nowadays, unfortunately. It can be difficult for the inexperienced to short the wheat from the chaff.
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I think you will be happy with the unit, Just make sure you have appropriate probes and only use 10X probes for now.
If you are going to purchase probes, people here can be helpful.
I have used scopes like the one you have purchased and the only thing that I really do not like is the GREEN screen. Reminds me of old computer screens.
If you tire of it, you can probably sell it and only take a minimal loss, which will be cheap compared to the experience you gain.
OH Aldo, thanks for your comment about bandwidth, my experience was that the bandwidth of a digital scope always fell off drastically after the advertised limit. It does so on my Agilent 54820. I guess it a bit like the analog scopes, you never know about the upper limit till you try the scope (and the probes).
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suggest simple 2 ch 10..20 MHz analog scope to start.
We have bought the fine German Hameg HM103, 204, 205 at street markets and fleas for EU 5, 25, 40!
All were from 1980s and worked fine, still using them
Check Ham fleas and local ads like Craig List (USA) or PaP.fr, le bon coin (France)
AVOID shipping any scope with a CRT.
Jon
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OH Aldo, thanks for your comment about bandwidth, my experience was that the bandwidth of a digital scope always fell off drastically after the advertised limit. It does so on my Agilent 54820. I guess it a bit like the analog scopes, you never know about the upper limit till you try the scope (and the probes).
I've recorded the frequency response with my SCPI script “just for you” (and a little bit for myself). :D
It is of course not a professional measurement, the source is the TinySA Basic and V/div is 500mV.
It doesn't look exactly flat, but it is above -3dB up to approx. 165MHz.
The fluctuations before are 1.5dB max. (scale is on the left, ignore the green line and phase scale).
Are more expensive scopes better (flatter frequency response)? I suspect so, but I have no idea.
Anyway, it's within specs, afaics.