Should I Buy the Finrsi DSO510 on a Tight Budget?

[osmax_br]

I am am a hobbyist who works on ESP32 projects, TFT displays, I2C devices, and does some circuit debugging here and there. I'm looking to buy an oscilloscope on a budget, specifically thinking about the Finrsi DSO510 (10 MHz, 48 MS/s, + 50 kHz function generator). My budget is very tight, around $30.

Of course, my question is NOT whether it is as good as a $300-$400 oscilloscope. My question is: Is it usable or somewhat useful for my work scenarios, or is it just a complete $30 waste of money, essentially e-garbage? Should I avoid buying it altogether and be without an oscilloscope?

I don't currently have any oscilloscope and can't afford a proper one for the next 4 years until I'm out of debt. Should I get the DSO510, or would I be better off waiting 4 years to save up for a $300 one?

[tunk]

For a bit more you can get the Zeeweii DSO1C81 (80MHz, 250MSps).

[Psi]

Are the BNC grounds connected to mains/USB earth on the Zeeweii DSO1C81 ?

[artag]

It's essentially a learning tool or toy due to low speed and single channel. It isn't enough to debug your intended targets - it can tell you there's a signal but not what the data is, for example.

 It may be useful enough to give you a feel for using an oscilloscope, show gross errors such as shorted wiring etc. Kind of like a DMM oir logic probe with just a little more information but frustrating lack of ability. It will tell you something about what you want in a real scope.

If it's all you can afford it may better than nothing but I would still aim to replace it with a 2-channel 50MHz (better still 100MHz) unit as soon as you have the money. If buying this makes that significantly harder then that may be a mistake.

I would suggest you save up for something better but fill the gap in your knowledge other ways. Maybe join a hackspace and use their equipment (though this too has a cost). Maybe look out for someone givinmg away an old analogue oscilloscope. Most will be better than this one - digital oscilloscopes have to be pretty good to be better than a 50 year old tektronix.

Specifically for the I2C/SPI etc jobs, get a $10 USB logic analyser. It will have enough channels to do something useful for digital debug and does something that an old analog can't do - storage. I'm assuming you have a PC to run it - a phone isn't enough.

[Fungus]

Any 'scope is better than no 'scope at all so get whatever you can.

For a bit more you can get the Zeeweii DSO1C81 (80MHz, 250MSps).

I think Zeeweii make better 'scopes than FNIRSI. Get FNIRSI for power supplies, Zeeweii for 'scopes.

The higher bandwidth and sample rate of the DSO1C81 will make a huge difference on the digital signals produced by an ESP32.

[osmax_br]

For a bit more you can get the Zeeweii DSO1C81 (80MHz, 250MSps).

OMG thanks , it is only 10$ more , but I honestly think it is like "too good to be true"
Did try one or know someone who tried it?

[Peabody]

The least expensive two-channel scope I've seen is the SC02.  The manufacturer is a mystery, but you can get it at Aliexpress for about $40 including two probes:

https://www.aliexpress.us/item/3256807551530702.html

Edit:  Here's another seller at a lower price - about $35 with two probes:

https://www.aliexpress.us/item/3256806585989509.html

I know nothing about it, and have never seen any comments here from anyone who uses it.  But the price is certainly right if it's any good.  Here's a video review:

[tunk]

Did try one or know someone who tried it?

There's one user report here:
https://www.eevblog.com/forum/testgear/zeeweii-dso1c81/msg5741961/#msg5741961

[tggzzz]

I am am a hobbyist who works on ESP32 projects, TFT displays, I2C devices, and does some circuit debugging here and there. I'm looking to buy an oscilloscope on a budget, specifically thinking about the Finrsi DSO510 (10 MHz, 48 MS/s, + 50 kHz function generator). My budget is very tight, around $30.

Of course, my question is NOT whether it is as good as a $300-$400 oscilloscope. My question is: Is it usable or somewhat useful for my work scenarios, or is it just a complete $30 waste of money, essentially e-garbage? Should I avoid buying it altogether and be without an oscilloscope?

I don't currently have any oscilloscope and can't afford a proper one for the next 4 years until I'm out of debt. Should I get the DSO510, or would I be better off waiting 4 years to save up for a $300 one?

Yes, repeat no

Scopes show analogue waveform shape and timing.

Strategy for digital circuits: use an analogue domain tool (i.e. a scope) to ensure analogue signal integrity (voltages, timing), then flip to the digital domain and debug digital signals with digital domain tools (i.e. logic/protocol analyser or printf()). Signal integrity can be assured by ensuring repetitive waveforms. That implies that a storage scope is not necessary.

Realise that the clock frequency of a digital circuit is irrelevant; the only important parameter is the rise/fall time. Then you need BW >0.35/t_risetime. A scope's samples/second spec is less important.

Any working scope which can deal with the edge rates and voltages is better than no scope. Having said that, with sufficient understanding and imagination, a heck of a lot can be done with some switches, LEDs, voltage sources, and a DVM. That was all I had when I designed my first computer, a 6800 with 128 bytes of RAM. (No, you couldn't fit an SMS message in that!)

If money is tight then realise

• Logic/protocol analysers can be very cheap and sufficient for many purposes.
• Second-hand analogue scopes can be very cheap and sufficient for many purposes - provided they are working. Beginners shouldn't want to have to fix their scope

Alternatively try to find a local hackspace/makerspace, and use their tools.

[nctnico]

I recommend against getting an analog scope. It will be way less usefull compared to anything digitial for the single shot feature alone.

To the OP: don't look at specs alone but try to find reviews from people and pay attention to their remarks where it comes to the user interface. Better specifications mean very little if the user interface makes a device hard to use.

[osmax_br]

The least expensive two-channel scope I've seen is the SC02.  The manufacturer is a mystery,

Edit:  Here's another seller at a lower price - about $35 with two probes:

https://www.aliexpress.us/item/3256806585989509.html

In the product description it says

Dual channel oscilloscope with 50M sampling rate, 2MHz actual bandwidth, and 10MHz analog bandwidth.

I didnt understand how it has 2 bandwidths actually
But thx for the suggestion, still 2ch is better than one

[tggzzz]

I recommend against getting an analog scope. It will be way less usefull compared to anything digitial for the single shot feature alone.

To the OP: don't look at specs alone but try to find reviews from people and pay attention to their remarks where it comes to the user interface. Better specifications mean very little if the user interface makes a device hard to use.

The OP is cash-strapped.

10/20MHz analogue scopes are almost free nowadays. Certainly my local hackspace seems to be given them on a regular basis. Look at fleabay or gumtree, find a local one, verify it works.

Single shot digital signals can be captured perfectly well with a very cheap logic analyser. In many cases that will be better than a low-end scope, digitising or otherwise.

The number of times I've had to debug single-shot analogue signals is very limited. If the OP's use-cases include those, then a digitising scope is necessary; if not, a DSO is optional.

If I had to choose between

• a moderate working analogue scope plus a basic logic analyser
• a low-end new digitising scope plus nothing else

then I would choose the first option.

That would leave money available for the other things the OP has yet to discover they need.

[tggzzz]

The least expensive two-channel scope I've seen is the SC02.  The manufacturer is a mystery,

Edit:  Here's another seller at a lower price - about $35 with two probes:

https://www.aliexpress.us/item/3256806585989509.html

In the product description it says

Dual channel oscilloscope with 50M sampling rate, 2MHz actual bandwidth, and 10MHz analog bandwidth.

I didnt understand how it has 2 bandwidths actually
But thx for the suggestion, still 2ch is better than one

Digitising scopes are complex, and their internal operation is not intuitively easy for a beginner to understand; beginners often mislead themselves. That's reflected in the specifications; there are many ways in which manufacturers  can and do highlight irrelevant numbers simply because they are impressively large.

Analogue scopes are much simpler, and the specifications are correspondingly simple. All the controls are visible on the front panel, whereas digitising scopes usually have some important controls buried within a menu structure.

I haven't checked, but it might be that the scope bandwidths you mention are higher for repetitive waveforms and lower for single shot waveforms. That's a classic trick manufacturers play[1].


[1] long ago I used a high-end HP scope with a 1GHz bandwidth but only 25MS/s, i.e. 1GHz for repetitive waveforms but ~50MHz for single shot waveforms.

[ledtester]

I am am a hobbyist who works on ESP32 projects, TFT displays, I2C devices, and does some circuit debugging here and there. ...

Since you deal a lot with digital signals save $10 for one of these logic analyzers:

Low cost logic analyzer -- Mr.T's Design Graveyard
https://youtu.be/3IA_6MwInVg

[deadly_penguin]

$30 is pushing it - I'd usually say not to bother with a super cheap new scope as not being worth the hassle, but with that budget... £30 on fleabay here only usually runs to a knackerd museum piece (at best), though there are a couple of Hantek USB scopes right now that might be okay.
As others have said a cheap logic probe paired with a cheap meter (an Aneng an8002/8?) might be better.

[OLderDan]

another great logic analyser option (mine still lives on a breadboard!) is using an old android phone/tab with a raspberry pico (if you use the W version you can connect with wifi or usb) and the free scoppy app. I use it often to confirm spi or i2c or uart on my arduino/esp32/pi projects beffore i switch to my pc based logic analyser through pulseview to use the decoding plugins.

[tggzzz]

another great logic analyser option (mine still lives on a breadboard!) is using an old android phone/tab with a raspberry pico (if you use the W version you can connect with wifi or usb) and the free scoppy app. I use it often to confirm spi or i2c or uart on my arduino/esp32/pi projects beffore i switch to my pc based logic analyser through pulseview to use the decoding plugins.

For working with i2c, spi, uarts,  etc etc, consider a BusPirate5. It also acts as a small PSU, simple logic analyser and even a 0.5MS/s oscilloscope.

Benefit: it enables you to capture the information (i.e. decode the digital signals) and also to generate the signals. Hence you can use it to peek and poke peripherals.

[nctnico]

While those logic analysers may be handy for protocol decoding, I'd prioritize on getting an oscilloscope. An oscilloscope shows you the actual signal. There can be a million things wrong with a signal which you won't catch using a logic analyser.

[tggzzz]

While those logic analysers may be handy for protocol decoding, I'd prioritize on getting an oscilloscope. An oscilloscope shows you the actual signal. There can be a million things wrong with a signal which you won't catch using a logic analyser.

That argument works both ways round.

There can be a million things wrong with digital signals that you won't catch with a scope.

Consider "long" sequences of two-way messages between a processor and one or more devices on a bus.

[osmax_br]

another great logic analyser option (mine still lives on a breadboard!) is using an old android phone/tab with a raspberry pico (if you use the W version you can connect with wifi or usb) and the free scoppy app. I use it often to confirm spi or i2c or uart on my arduino/esp32/pi projects beffore i switch to my pc based logic analyser through pulseview to use the decoding plugins.

It is actually really solid idea , thanks !

[osmax_br]

The OP is cash-strapped.

10/20MHz analogue scopes are almost free nowadays. Certainly my local hackspace seems to be given them on a regular basis. Look at fleabay or gumtree, find a local one, verify it works.

Single shot digital signals can be captured perfectly well with a very cheap logic analyser. In many cases that will be better than a low-end scope, digitising or otherwise.

The number of times I've had to debug single-shot analogue signals is very limited. If the OP's use-cases include those, then a digitising scope is necessary; if not, a DSO is optional.

If I had to choose between

• a moderate working analogue scope plus a basic logic analyser
• a low-end new digitising scope plus nothing else

then I would choose the first option.

That would leave money available for the other things the OP has yet to discover they need.

Well I actually got a free analog oscilloscope, it is a 20 MHz goldstar os9020g with a function gen , it worked fine 2,3 times and then died , I tried fixing it but it is very complicated circuit (1000s of components) + I get terrified when poking around HV CRT while not having enough experience, I finally gave up and gave it to a friend of mine who repairs board issues on laptops and he told me that he  wasn't able to find the problem
Since I have very little experience on this stuff (especially reverse engineering and repairs) I concluded that I am better buying a cheap dso since I didn't find any other analog scope in my local area
Also , do you have any suggestions for a course to get comfortable with repairs and reverse engineer circuits , do you recommend watching "old oscilloscope repair" videos on YouTube or that's a waste of time and you'd be better on a proper course online on Udemy or yt
+ I am the same guy who was asking about pursuing electronics as a med student , you always reply on all posts , thanks for your help and time

[tggzzz]

Well I actually got a free analog oscilloscope, it is a 20 MHz goldstar os9020g with a function gen , it worked fine 2,3 times and then died , I tried fixing it but it is very complicated circuit (1000s of components) + I get terrified when poking around HV CRT while not having enough experience, I finally gave up

Good decision

Also , do you have any suggestions for a course to get comfortable with repairs and reverse engineer circuits , do you recommend watching "old oscilloscope repair" videos on YouTube or that's a waste of time and you'd be better on a proper course online on Udemy or yt

No, I don't.

Be aware that design and repair are very different in all ways. While there is a lot of overlap, it is enlightening to turn up the contrast and consider the differences. Hence simplistically...

Repair is about understanding something that already exists. It doesn't require that you understand how the circuit works. It is mainly understanding the symptoms of failure, understanding what typically fails, looking at components carefully to spot gross failures, following test procedures to localise failures, knowing how to repair failures and having the coordination skills. The first of those have a lot in common with doctors, with where the specific published test procedures are the NICE guidelines The latter are more nurse/technician skills. It it quite often beneficial to have an older experienced person diagnosing the problem, and a younger less decrepit person doing the repair.

Design is about working out and understanding the problem you are trying to solve. You need to understand the maths and physics of the system you are creating, components ideal and non-ideal behaviour, how they are typically put together to minimise the non-ideal behaviour. Beginners worry about how the system will work; professionals worry about how the working system will fail (and how to ameliorate that).

EDIT: if you want to have a quick overview of repairing equipment, skim the blue paragraphs in https://emperoroftestequipment.weebly.com/ and look at the summary section near the bottom. There are many different types of equipment mentioned, but you will be able to see some recurring themes: electrolytic capacitors and switch contacts.

Skimming that is much much faster and more than listening to dozens of talking heads s-l-o-w-l-y droning on in a yoootooob vid. No surprises there

[tautech]

Well I actually got a free analog oscilloscope, it is a 20 MHz goldstar os9020g with a function gen , it worked fine 2,3 times and then died , I tried fixing it but it is very complicated circuit (1000s of components) + I get terrified when poking around HV CRT while not having enough experience, I finally gave up

Good decision

Also , do you have any suggestions for a course to get comfortable with repairs and reverse engineer circuits , do you recommend watching "old oscilloscope repair" videos on YouTube or that's a waste of time and you'd be better on a proper course online on Udemy or yt

No, I don't.

Be aware that design and repair are very different in all ways. While there is a lot of overlap, it is enlightening to turn up the contrast and consider the differences. Hence simplistically...

Repair is about understanding something that already exists. It doesn't require that you understand how the circuit works. It is mainly understanding the symptoms of failure, understanding what typically fails, looking at components carefully to spot gross failures, following test procedures to localise failures, knowing how to repair failures and having the coordination skills. The first of those have a lot in common with doctors, with where the specific published test procedures are the NICE guidelines The latter are more nurse/technician skills. It it quite often beneficial to have an older experienced person diagnosing the problem, and a younger less decrepit person doing the repair.

Design is about working out and understanding the problem you are trying to solve. You need to understand the maths and physics of the system you are creating, components ideal and non-ideal behaviour, how they are typically put together to minimise the non-ideal behaviour. Beginners worry about how the system will work; professionals worry about how the working system will fail (and how to ameliorate that).

EDIT: if you want to have a quick overview of repairing equipment, skim the blue paragraphs in https://emperoroftestequipment.weebly.com/ There are many different types of equipment mentioned, but you will be able to see some recurring themes: electrolytic capacitors and switch contacts.

Skimming that is much much faster and more than listening to dozens of talking heads s-l-o-w-l-y droning on in a yoootooob vid. No surprises there

Yeah well I started this road with nothing more than a MC meter and unregulated soldering iron !

Was gifted a busted 60 MHz CRO and at that time no manuals were available for it online but paper copies from the UK were.
Many components were obsolete for that old Telequipment D83 but repaired and serviceable it became and sent me down the road of acquiring any cheap broken CRO I could find, with 1 proviso, full manuals for it must be available !
Quickly I had to accept the EHT levels of -2750V were to be the norm and just make the best of it....safely !

I fixed many CRO's until discovering the power of a DSO and after repairing a few Tek DSO's and them selling very well luckily enough I was Johnny on the spot to grab an upcoming brand agency......

There are times one must be brave......

[osmax_br]

Thank you all for your advice
I've decided to get an analog oscilloscope, for around 30$ I got goldstar os9020g 20mhz + 1mhz func gen

I know that it wouldn't be very useful for my digital work , since I do mostly work on esp32 , i2c , spi ,TFT screens ETC.....
However as many mentioned ,  This 30$ dso is the worst of both worlds
So I would probably get a 10$ logic analyzer in addition to my analog oscilloscope

Any suggestions or adivce?

[tggzzz]

I've decided to get an analog oscilloscope, for around 30$ I got goldstar os9020g 20mhz + 1mhz func gen

I know that it wouldn't be very useful for my digital work , since I do mostly work on esp32 , i2c , spi ,TFT screens ETC.....

That's a simple instrument - which is beneficial for a beginner.

With some imagination and understanding, it will be useful for your digital work[1]. The main limitation is that its risetime will be 17ns, so it won't display transients faster than that.

Depending on what tests you want to do with i2c etc, a BusPirate5 may be helpful, since it can record and generate a variety of digital bus signals. OTOH, if you are just recording digital signals generated by other devices, then a simple $10 data recorder (plus software for post-processing) may well be sufficient.

So, have fun, learn to use your instruments to their fullest, and afterwards you will be in a better position to define what you do and don't need in another instrument.

[1] I designed and built my first computer (with 128bytes of RAM) using LEDs and a voltmeter, plus an oscilloscope to measure signal integrity on one line.