what an oscilloscope recommended for a woman passionate about electronics?

[CharlotteSwiss]

thanks borjam, Oculus and alseta; now I go to work until late in the evening (touches me), then I will reply to your messages 

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

meanwhile on the table I have my first repair I also have the new oscilloscope available. Logitech sound card (low cost), 2 satellites and subwoofer, no sound comes out. For now I haven't checked out much, power supply is ok (12vDc).
I think the problem is the STA540 amplifier.
I see from the datasheet which also has a pin 10 for diagnostics.
Here I have no risk of voltage, I could start taking some measurements with the oscilloscope.
Let's see if I can understand how the siglent could be useful on this repair
This card can be a good school to learn with this new toy 
See you soon

[ArthurDent]

Going back to one of the screen saves you posted in reply #329, the scope was set incorrectly and that may be why you were seeing garbage. I didn’t see where anyone noticed that the timebase was set to 20mS which is not what you want for a 31.31Khz signal. Below is a screen save I did with the timebase on my Siglent set to 20uS to display the same 31.31Khz frequency sine wave from my function generator properly. You can see that the sine wave is very clean and that allows the trigger to work properly on an exact point on the waveform. I also made some adjustments to the image in Photoshop to make the gridlines and other stuff look better.

One thing that might help is something I learned back when we used sliderules and had to keep track of exponents and powers in our heads or we’d be off by several orders of magnitudes in our answers. Do a quick check of where you know where the answer should be. For example, if you’re going to display a 1Mhz waveform, 1Mhz has a period of 1uS; 100Khz=10uS; 10Khz 100uS; and 1Khz=1mS. You had the timebase set to 20mS about 1000 times too slow. Digital scopes don’t like errors like this and can display garbage. It might help when you are trying to set the timebase for some signal to start at the fastest speed and switch down until you see the signal. 

[rstofer]

One thing that might help is something I learned back when we used sliderules and had to keep track of exponents and powers in our heads or we’d be off by several orders of magnitudes in our answers. Do a quick check of where you know where the answer should be. For example, if you’re going to display a 1Mhz waveform, 1Mhz has a period of 1uS; 100Khz=10uS; 10Khz 100uS; and 1Khz=1mS. You had the timebase set to 20mS about 1000 times too slow. Digital scopes don’t like errors like this and can display garbage. It might help when you are trying to set the timebase for some signal to start at the fastest speed and switch down until you see the signal.

I just remember '1000'.  Then it becomes an issue of getting the units right.  5 MHz into 1000 is 200 ns.  2 kHz into 1000 is 500 us. 

[tggzzz]

1Mhz has a period of 1uS

1 microMho/microSiemen? Really?

Perhaps you mean 1us/1µs?

(That's a pet hate of mine )

[ArthurDent]

1Mhz has a period of 1uS

1 microMho/microSiemen? Really?

Perhaps you mean 1us/1µs?

(That's a pet hate of mine )

What I wrote was uS, not us or U.S.. I also write uF for microfarad. The same as I write Mhz for megahertz (or sometimes mc for megacycles) and mHz for milihertz. I understood, as I'm sure others did, while, oops, whilst reading it. 

"A microsecond is an SI unit of time equal to one millionth (0.000001 or 10−6 or ​1⁄1,000,000) of a second. Its symbol is μs, sometimes simplified to us when Unicode is not available."

[tggzzz]

1Mhz has a period of 1uS

1 microMho/microSiemen? Really?

Perhaps you mean 1us/1µs?

(That's a pet hate of mine )

What I wrote was uS, not us or U.S..

Which is is wrong. S is the abbreviation for the S.I. unit Siemens. https://en.m.wikipedia.org/wiki/Siemens_(unit)

I also write uF for microfarad.

Correct.

The same as I write Mhz for megahertz

Wrong. The S.I. unit is Hertz, abbreviated Hz.

You really need to understand https://en.m.wikipedia.org/wiki/International_System_of_Units#Derived_units

(or sometimes mc for megacycles) and mHz for milihertz.

Obsolescent, and correct respectively. Although m/c was common.

I understood, as I'm sure others did, while, oops, whilst reading it. 

"A microsecond is an SI unit of time equal to one millionth (0.000001 or 10−6 or ​1⁄1,000,000) of a second. Its symbol is μs, sometimes simplified to us when Unicode is not available."

And "S" is the unit of conductance, not time.

I suggest you had a look at data sheets for components such as FETs. There they have to get it right: see the unit of the principal parameter g_m and the unit for transition times.

[Labrat101]

GIRLS stop fighting over S.I  also the chemical formula for silicon "" used in Head & shoulders ""   & lesser used in electronics   

 We all understood you Arthur they are taking the miky   

  hertz    Hz    frequency    s−1   (That is 'S' to the minus One )

 

Which is is wrong. S is the abbreviation for the S.I. unit Siemens. https://en.m.wikipedia.org/wiki/Siemens_(unit)

That link is a search error and it says so as well  ...'' S'' is not the abbreviation for the S.I. ''  S.I is the only abbreviation. as it has already been abbreviated.   S on it's own means 'S' it usually comes before 'T'
"" Dialog-information on.svg   Did you mean: Siemens (unit)? ""
If your referring to FET's   which have nothing to do with the subject S= source, G=Gate, D=drain,
  No Hertz only if you touch it when connected to 200volts ,,.. 

[CharlotteSwiss]

Just as any (working!) oscilloscope is better than no oscilloscope at all, it is also true that just about any working signal generator or function generator is better than no signal generator at all. The two instruments are born companions and are lonely without one another.

They are great fun to play with while exploring the oscilloscope, and are even very useful in the audio repair lab. Inject an audio signal of known parameters into the input of an audio circuit, use the oscilloscope to follow it through the circuitry node by node until it gets wonky or disappears -- and you have located your fault!

For under 5 USD you can build a 555-based signal generator that will produce sine (nearly), square with variable duty cycle, triangle ramp waveforms. Even such a little toy is useful in many ways.

examples: https://www.instructables.com/id/Oscillator-circuits-for-the-555-timer/

I would not use my cellphone or computer for troubleshooting faults in circuits. Better to use a standalone signal generator; even a cheap one will be better in many ways than using a general purpose and expensive gadget like a phone or computer.

you must have the crystal ball, it seems that you have read in my mind 
The idea of ​​taking the oscilloscope came to me exactly to then be able to follow a signal in audio circuits, but obviously also in other types of circuits. I also took it for another reason, I like learning new things, then if I use it a little while ago nothing. The signal generator, as I have said many times in this discussion, will be the next purchase; first, however, I want to at least learn the basics of this siglent, without heaping too many things together ... Maybe building it for now is a difficult task for me, I just need to buy it, I will ask here in the forum when it will be now.
Note: I tried the audio signal online via PC only for lack of signals, certainly I will not rely on that.
Then, by chance, the other day a friend of mine made the usual joke: "what do you mean, you couldn't settle me .."
Obviously I am scarce, but when they entrust me with something I feel important ...
And so I have here on the table a small sound card (logitech) of a 2 speaker + sub system that no longer rings ... it will make me the first patient in the operating room .. Normally I only operated with a multimeter, but now that I have the oscilloscope I absolutely want to find the fault using this new instrument, even at the cost of doing some damage 
I still don't understand much about this tool, but I'll stick it somewhere on the board and it should tell me something
thanks 

[tggzzz]

GIRLS stop fighting over S.I  also the chemical formula for silicon "" used in Head & shoulders ""   & lesser used in electronics   

I haven't seen any technical person get those two mixed up. Journalists and HRdroids perhaps

We all understood you Arthur they are taking the miky   

  hertz    Hz    frequency    s−1   (That is 'S' to the minus One )

Ah, the virtues of the "sup" tag button: you mean "Hertz  Hz    frequency    s⁻¹   (That is 'S' to the minus One )

[CharlotteSwiss]

A good function generator and a good pulse generator are both useful to have around. With a reasonably fast pulser, and a tee connector, you can do crude TDR with your scope to measure the length of a piece of coax, find a fault in a coax, etc.

I will need an instrument to be able to put a programmed signal (sinusoidal, square, etc.) into a piece of circuit, to then monitor with the oscilloscope how it behaves in its path: I think I need a function generator if I'm not mistaken
(as for the oscilloscope, I start from scratch also for that instrument)
the only signal that I can input now is direct voltage with the bench top power supply ...
thanks 

[CharlotteSwiss]

Perfect. That's what I meant but I didn't remember the actual values involved.
So you see you can't obtain a useful trigger outside of that interval in this particular case. Setting the trigger level to, say, 1 V means "trigger when the voltage hits 1 V and it is raising". If you try to trigger on a mostly "horizontal" part of the signal you won't obtain a clear image, as you just saw

1 week ago I didn't even know what the trigger was 
now at least I know it is used to trigger the signal by showing it on the display. I also learned that it must be somewhere in the signal ramp, and not in the flat signal openers; this means that a stable and visible wave can be seen on the display
thanks 

[CharlotteSwiss]

Going back to one of the screen saves you posted in reply #329, the scope was set incorrectly and that may be why you were seeing garbage. I didn’t see where anyone noticed that the timebase was set to 20mS which is not what you want for a 31.31Khz signal. Below is a screen save I did with the timebase on my Siglent set to 20uS to display the same 31.31Khz frequency sine wave from my function generator properly. You can see that the sine wave is very clean and that allows the trigger to work properly on an exact point on the waveform. I also made some adjustments to the image in Photoshop to make the gridlines and other stuff look better.

One thing that might help is something I learned back when we used sliderules and had to keep track of exponents and powers in our heads or we’d be off by several orders of magnitudes in our answers. Do a quick check of where you know where the answer should be. For example, if you’re going to display a 1Mhz waveform, 1Mhz has a period of 1uS; 100Khz=10uS; 10Khz 100uS; and 1Khz=1mS. You had the timebase set to 20mS about 1000 times too slow. Digital scopes don’t like errors like this and can display garbage. It might help when you are trying to set the timebase for some signal to start at the fastest speed and switch down until you see the signal.

thanks for the explanation, I have to read well and try to understand how to find the ideal time, I admit that I had no idea; and since it doesn't take us by car ... I have to learn how to manually set the parameters!
Maybe I'll start with the trick you mentioned, start with fast times .. and then decrease until I see the signal on the display ...
Note on that screen of mine: the time I had put at random, or rather the first that showed me something human on the display. The frequency of the signal was however 15Hz (as per grid), the 31 khz on the display were false (then we understood that by setting coupling HF the frequency was highlighted right)
 

[rstofer]

You can Google for "cheap sine wave generator".  There are several ways of building this kind of thing and Amazon has several:

https://www.amazon.com/s?k=sine+wave+generator&ref=nb_sb_noss_1

Any of these will hold you until you decide you need a professional Arbitrary Waveform Generator (the Siglent SDG 20x2-X is a good series and I have the SDG 2082-X version (80 MHz).  That can come later and lower frequency models are cheaper.

Or, you can buy that Arduino and follow along here:

https://forum.arduino.cc/index.php?topic=361759.0

But, yes, you need a signal source.

[CharlotteSwiss]

You can Google for "cheap sine wave generator".  There are several ways of building this kind of thing and Amazon has several:

https://www.amazon.com/s?k=sine+wave+generator&ref=nb_sb_noss_1

Any of these will hold you until you decide you need a professional Arbitrary Waveform Generator (the Siglent SDG 20x2-X is a good series and I have the SDG 2082-X version (80 MHz).  That can come later and lower frequency models are cheaper.

Or, you can buy that Arduino and follow along here:

https://forum.arduino.cc/index.php?topic=361759.0

But, yes, you need a signal source.

oh yes, give me time to know how to play at least minimally with the oscilloscope, then I take a signal generator (not only sinusoid though ..)
 

[CharlotteSwiss]

While you're at it another small exercise:
Trigger Setup, select Falling or Alternate and see what they each do. 

rising (default): the trigger point falls on the rise of the signal
falling: the trigger point falls on the descent of the signal
alternate: the trigger point falls alternately on descent / ascent / descent etc. etc.



 

[jiangtao.lv]

The virtual USB Oscilloscope may help,I recommend OSCA02L:
https://www.amazon.com/Oscilloscope-2-Channel-Bandwidth-4-Channel-Resolution/dp/B07RP9N2BZ/ref=sr_1_4?dchild=1&m=AR89OCDME10MV&marketplaceID=ATVPDKIKX0DER&qid=1593655482&s=merchant-items&sr=1-4


www.lotoins.com

[jiangtao.lv]

and a Tutorial video for you:

[tggzzz]

You can Google for "cheap sine wave generator".  There are several ways of building this kind of thing and Amazon has several:

https://www.amazon.com/s?k=sine+wave+generator&ref=nb_sb_noss_1

Any of these will hold you until you decide you need a professional Arbitrary Waveform Generator (the Siglent SDG 20x2-X is a good series and I have the SDG 2082-X version (80 MHz).  That can come later and lower frequency models are cheaper.

Or, you can buy that Arduino and follow along here:

https://forum.arduino.cc/index.php?topic=361759.0

But, yes, you need a signal source.

oh yes, give me time to know how to play at least minimally with the oscilloscope, then I take a signal generator (not only sinusoid though ..)
 

alsetalokin4017's suggestion that you build a 555 based timer is a good one. The expected waveforms are well defined in the datasheet (and ought to be in tutorials), and you will learn a lot examining them and playing with various controls on the scope. Examples:
https://www.ebay.co.uk/itm/Student-electronics-timer-kit-555/254640078508 (caution: contains the devil's tool: a solderless breadboard )
https://www.ebay.co.uk/itm/5-12V-NE555-Adjustable-Frequency-Timer-Module-Resistance-Pulse-Generator-Arduino/173954576885

You won't even need a PSU, since you can use a 9V battery.

[CharlotteSwiss]

The virtual USB Oscilloscope may help,I recommend OSCA02L:

I just bought the siglent, however thanks for the suggestion
 

[CharlotteSwiss]

alsetalokin4017's suggestion that you build a 555 based timer is a good one. The expected waveforms are well defined in the datasheet (and ought to be in tutorials), and you will learn a lot examining them and playing with various controls on the scope. Examples:
https://www.ebay.co.uk/itm/Student-electronics-timer-kit-555/254640078508 (caution: contains the devil's tool: a solderless breadboard )
https://www.ebay.co.uk/itm/5-12V-NE555-Adjustable-Frequency-Timer-Module-Resistance-Pulse-Generator-Arduino/173954576885

You won't even need a PSU, since you can use a 9V battery.

I try to look at the datasheet better then. But now I have to focus more on learning the basics of the oscilloscope, then I'll focus more on the signal generator. If I take that now too, I mess up my head (already confused)
thanks 

[tggzzz]

alsetalokin4017's suggestion that you build a 555 based timer is a good one. The expected waveforms are well defined in the datasheet (and ought to be in tutorials), and you will learn a lot examining them and playing with various controls on the scope. Examples:
https://www.ebay.co.uk/itm/Student-electronics-timer-kit-555/254640078508 (caution: contains the devil's tool: a solderless breadboard )
https://www.ebay.co.uk/itm/5-12V-NE555-Adjustable-Frequency-Timer-Module-Resistance-Pulse-Generator-Arduino/173954576885

You won't even need a PSU, since you can use a 9V battery.

I try to look at the datasheet better then. But now I have to focus more on learning the basics of the oscilloscope, then I'll focus more on the signal generator. If I take that now too, I mess up my head (already confused)
thanks 

When first learning how to use a scope, in physics lessons at school, I found it very useful to have a real-world waveform to inspect. Clearly there is a balance between simplicity and complexity.

The advantage I had was that they were simple analogue scopes, not modern complex digitising scopes with many many controls that can be and must be understood.

[dietert1]

Some people consider those low cost Chinese scopes toys. They are fancy, almost like computer games.

Yesterday i discovered another bug in our Rigol: I had setup the screen with infinite persistence to discover rare signal errors (missing pulse) and by chance some serial decoding was active (without on-screen result). Bug: No persistence at all in that configuration. I kept the scope running all night waiting for error records, to no avail. As soon as i turned off that decoder, i had the first exception record after 40 seconds. Then i used the missing pulse trigger to get a nice and clean image. That worked well..

Regards, Dieter

[ArthurDent]

CharlotteSwiss - "I try to look at the datasheet better then. But now I have to focus more on learning the basics of the oscilloscope, then I'll focus more on the signal generator. If I take that now too, I mess up my head (already confused)"

It isn't too early to start looking at function generators. There are many out there but judging from what you have said so far I believe you would want to buy a new fairly inexpensive unit with a lot of features. One function generator worth considering is the FeelTech FY6900-60M that cost between $100 and $130USD. You can find function generators that cost 20 times more than the FY6900 but for a good hobbyist function generator, this is one to consider. If you google you can find lots of videos and written reviews on the FY6900.

If you start looking now you can get lots of recommendations, consider the various features, and when you're ready to buy, make an informed choice. 

[Electro Fan]

CharlotteSwiss - "I try to look at the datasheet better then. But now I have to focus more on learning the basics of the oscilloscope, then I'll focus more on the signal generator. If I take that now too, I mess up my head (already confused)"

It isn't too early to start looking at function generators. There are many out there but judging from what you have said so far I believe you would want to buy a new fairly inexpensive unit with a lot of features. One function generator worth considering is the FeelTech FY6900-60M that cost between $100 and $130USD. You can find function generators that cost 20 times more than the FY6900 but for a good hobbyist function generator, this is one to consider. If you google you can find lots of videos and written reviews on the FY6900.

If you start looking now you can get lots of recommendations, consider the various features, and when you're ready to buy, make an informed choice.

+1 for it isn't too early to start looking at function generators

For a new oscilloscope user having some reasonably well understood signal to observe (sine waye, square wave, etc.) and having some control over frequency and amplitude will make learning scope operations easier to learn.  With proper BNC cables and terminators (or built-in impedance controls) the generator+scope tandem will also help with understanding impedance matching, and RMS vs average vs peak measurements, etc.  The FeelTech generators are probably good candidates to consider.

[CharlotteSwiss]

When first learning how to use a scope, in physics lessons at school, I found it very useful to have a real-world waveform to inspect. Clearly there is a balance between simplicity and complexity.

The advantage I had was that they were simple analogue scopes, not modern complex digitising scopes with many many controls that can be and must be understood.

in fact, starting to study the manual, these digital oscilloscopes make things of it .. it will take me time to understand every detail, I like to learn everything it does.
But for now I just need to really understand the basics, in a week I already have a better vision, but I also have huge chasms, but gradually I will improve
 

Yesterday i discovered another bug in our Rigol: I had setup the screen with infinite persistence to discover rare signal errors (missing pulse) and by chance some serial decoding was active (without on-screen result). Bug: No persistence at all in that configuration. I kept the scope running all night waiting for error records, to no avail. As soon as i turned off that decoder, i had the first exception record after 40 seconds. Then i used the missing pulse trigger to get a nice and clean image. That worked well..

I know that almost all oscilloscopes have bugs, from what you read ... oh well they are not too frequent 

CharlotteSwiss - "I try to look at the datasheet better then. But now I have to focus more on learning the basics of the oscilloscope, then I'll focus more on the signal generator. If I take that now too, I mess up my head (already confused)"

It isn't too early to start looking at function generators. There are many out there but judging from what you have said so far I believe you would want to buy a new fairly inexpensive unit with a lot of features. One function generator worth considering is the FeelTech FY6900-60M that cost between $100 and $130USD. You can find function generators that cost 20 times more than the FY6900 but for a good hobbyist function generator, this is one to consider. If you google you can find lots of videos and written reviews on the FY6900.

If you start looking now you can get lots of recommendations, consider the various features, and when you're ready to buy, make an informed choice. 

Arthur as I am made, I prefer to concentrate on one thing at a time, otherwise I'll make a mess.
I spend a lot of time choosing the things I buy, and therefore starting now I would take away my free time dedicated to the oscilloscope, which unfortunately I know very little at the moment.
The 6900, however, I have already spotted it, it is easy because I usually buy on amazon, and then it would be about the maximum expense that I could spend on a generator. But I would say that I came across a discussion here on EEV about this generator, and heavy comments were flying ..
thanks for the suggestion 

+1 for it isn't too early to start looking at function generators
For a new oscilloscope user having some reasonably well understood signal to observe (sine waye, square wave, etc.) and having some control over frequency and amplitude will make learning scope operations easier to learn.  With proper BNC cables and terminators (or built-in impedance controls) the generator+scope tandem will also help with understanding impedance matching, and RMS vs average vs peak measurements, etc.  The FeelTech generators are probably good candidates to consider.

as I wrote above, all at the right time.
But I must admit that if I had already had it here, I could have generated precise waves, easy to study on the oscilloscope.
I will try to hurry to learn the basics of siglent at least, so then I concentrate that week to get an ideal generator for me, thanks