probes x1 or x10

[Adrian_Arg.]

hello, I have a rigol ds1054z, my first oscilloscope, and I am using it with arduino and small projects, I have many doubts, but one that appeared to me now is, the probes of it when working with voltages lower than 24 volts, it is necessary to place the probe in X10 of attenuation or is better to use it in X1.

[TK]

Most of the time it is better to set it to 10X as the load on the tested circuit will be 10Mohms, compared to 1Mohms on 1X setting.

[Adrian_Arg.]

ok, and at what time it is better to use them in X1, I thought that working with low voltages was better to use them in X1.

[Gyro]

It's not about voltage (well, until you blow your scope input by overloading it on X1  ), it's about loading on your circuit....

On the X1 setting, the circuit sees the whole capacitance of the scope coax lead (100pF or more), as well as the 1Meg input impedance of the scope. The capacitance is so high that it is not realistic to use it for medium to high frequencies.

On X10, the signal is attenuated but the capacitive loading is also reduced by a similar ratio and the resistive loading increased to 10Meg.

[Adrian_Arg.]

thanks for your time and the answer

[danadak]

Some background -


http://www.ni.com/white-paper/14825/en/


https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=5&ved=0ahUKEwjG9p217M3ZAhWOct8KHcHOCakQFghhMAQ&url=http%3A%2F%2Fweb.mit.edu%2F6.101%2Fwww%2Freference%2FABCprobes_s.pdf&usg=AOvVaw3jqTqjxTe5xhU8dQaIF70U


https://meettechniek.info/instruments/scope-probes.html


Regards, Dana.

[plazma]

And if you got Rigol probes the switch may not latch properly into 1x position. I got 4 extra probes for warranty because of that fault. The new probes had still the same fault.

The bandwidth is also lower in 1x mode.

[stefan_k133]

Hi,

Dave made a video on 1x probes:


And Alan posted another good probe tutorial:


Regards,
Stefan

[tggzzz]

hello, I have a rigol ds1054z, my first oscilloscope, and I am using it with arduino and small projects, I have many doubts, but one that appeared to me now is, the probes of it when working with voltages lower than 24 volts, it is necessary to place the probe in X10 of attenuation or is better to use it in X1.

Good to see someone that is thinking and asking questions.

To answer your immediate question, in most cases *10 is appropriate. If you have *1/*10 switchable probes then sooner or later you will have them in the "other" postion.

The key safety specs you should be aware of are (1) the scope input maximum voltage (2) the probe tip maximum voltage (3) the way the probe tip maximum voltage falls as the frequency increases.

There are also many different types of probe you; won't need most of them yet. However, you should know when your probes are insufficient and/or dangerous - so that you can stay away from those situations. FFI, have a look at the references in https://entertaininghacks.wordpress.com/library-2/scope-probe-reference-material/

[Adrian_Arg.]

I am careful because put in Argentina since tequipment, total cost was u $ s 610. that includes transportation and customs tax, you have to take care of it

[SirAlucard]

Hi,

Dave made a video on 1x probes:


And Alan posted another good probe tutorial:


Regards,
Stefan

Thanks for those videos, those are great.

[OLderDan]

I know, zombies... I am in exactly this situation, first cro (dso2d10 converted to 15) and I am usually playing with arduino or esp32 or pic etc and have wondered if I should be using 1x or 10x setting on my probes. After reading all the posts I am still left without a definitive answer. I understand using 10x offers a reduced loading on the circuit, but with logic levels of 5v or 3v, unless i am probing around the crystal, but rather uart, spi etc, does it really matter?
 
I notice spurious noise that isn't related to the actual signal that can only be reduced in 10x if I switch to HR mode (and lose sample depth) and also enable 20mhz filter. I have less issues enabling this because, well, I am working below 20mhz! I am really just trying to work as close to the actual signal so that I can learn he difference when I use the cro's features.

[Vovk_Z]

The rule for 10x/1x is really simple: use 10x always, until you really need 1x mode.   

[tggzzz]

I know, zombies... I am in exactly this situation, first cro (dso2d10 converted to 15) and I am usually playing with arduino or esp32 or pic etc and have wondered if I should be using 1x or 10x setting on my probes. After reading all the posts I am still left without a definitive answer. I understand using 10x offers a reduced loading on the circuit, but with logic levels of 5v or 3v, unless i am probing around the crystal, but rather uart, spi etc, does it really matter?
 
I notice spurious noise that isn't related to the actual signal that can only be reduced in 10x if I switch to HR mode (and lose sample depth) and also enable 20mhz filter. I have less issues enabling this because, well, I am working below 20mhz! I am really just trying to work as close to the actual signal so that I can learn he difference when I use the cro's features.

The only time to use *1 probes is when observing signals too small to be seen with a *10 probe.

Even *10 "high" impedance probes offer a very significant load to high speed logic signals: they aren't 10Mohm by many orders of magnitude! Plus their 6" ground lead causes ringing at ~100MHz.

Z0 or active probes are preferable.

High "speed logic" means any logic family introduced since the early 90s. I have a jellybean logic circuit with ~300ps edges, corresponding to 1GHz. 1ns/350MHz transition times are normal.

Don't forget that the speed is completely and utterly unrelated to clock frequency. The only thing that matters is the transition time. FFI: https://entertaininghacks.wordpress.com/2018/05/08/digital-signal-integrity-and-bandwidth-signals-risetime-is-important-period-is-irrelevant/

In anthropomorphic terms, the logic circuit neither knows nor cares when the next transition might occur.

In engineering terms, whether a clock single has the required monotonic transition depends on the transition time and the track length. Additionally, you can increase the setup time margin (t_su)by reducing the clock speed, but the equally important hold time margin is (t_hold) is unchanged.

In general, see the references at https://entertaininghacks.wordpress.com/library-2/scope-probe-reference-material/

[OLderDan]

Wow, I really am 60... Just noticed I was using the term cro, and thought about it for a sec... Lol, cathode ray oscilloscope might not be the correct term for my dso2d15!

[Wallace Gasiewicz]

Besides the possibility of exceeding the input volt max of your scope. tggxxx's point is very important. The scope leads "load down" the signal that is passed along after the scope contact point. So the signal after that point is less. The higher "X" your probe is, the less signal you are taking away from the signal path.
Perhaps not the best example but I just aligned a 100 Watt tube HF transmitter. The signal to the final grids is over 40 volts but just putting the 10X probe at this point decreased the output of the amp by more than half. The probe not only steals some power but changes the impedance at the point where you apply it.   
There are no Infinite impedance probes that would not affect a circuit. "Active" probes can take lass signal away from the circuit, but I do not think you want to get into that. (neither do I). Using a 1 X probe would screw up the signal path even more.   
Some circuits will stop working entirely if probed even with a 10X probe.  Like oscillators.   

Always use a 10X Probe unless you find a reason to use another one. This is very unlikely in your stated endeavors 

The rule for 10x/1x is really simple: use 10x always, until you really need 1x mode.   

There is another input into some scopes: that is a 50 Ohm input.  This is used for "Terminating" the signal.  The signal goes nowhere after this. The entire output of a device with a 50 ohm output is fed into the scope thru a coax line, not a probe.. You can do this with a signal generator and see the shape of the signal very well. I do not know if you will need this function at all.   

OLderDan:  60 ain't bad, just wait.

[tggzzz]

Besides the possibility of exceeding the input volt max of your scope. tggxxx's point is very important. The scope leads "load down" the signal that is passed along after the scope contact point. So the signal after that point is less. The higher "X" your probe is, the less signal you are taking away from the signal path.
Perhaps not the best example but I just aligned a 100 Watt tube HF transmitter. The signal to the final grids is over 40 volts but just putting the 10X probe at this point decreased the output of the amp by more than half. The probe not only steals some power but changes the impedance at the point where you apply it.

That power has to re-appear somewhere. Always check a probe's specified maximum voltage vs frequency.