Questions tagged [probe]
A physical device used to connect an electronic instrument (such as an oscilloscope) to a circuit in order to measure quantities such as voltage, current, temperature, etc. Use in conjunction with related tags such as "oscilloscope", "voltmeter", etc., as applicable.
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Driving 50 Ω coax cable for doing measurements with oscilloscope
This is a follow up question to Using 50 Ω coax cable instead of passive probe.
In the linked question I asked whether it would be possible to use a 50 Ω coax cable instead of the passive probe for ...
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Using 50 Ω coax cable instead of passive probe
Preface, why am I asking this question?
Instead of using a passive probe with a ground clip, I want a more "permanent" and reliable connection for my measurements. Note: I'm not talking ...
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Looking for a short sharp pin [closed]
I'm looking for a short pin with a sharp point, to be used for probing a circuit. Similar to a scope probe tip, but for a dedicated custom PCB.
Ideal length of <5mm, diameter of <1mm, solderable....
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Circuit works only when oscilloscope probe is connected and does not work otherwise
I have built the circuit shown below.
The problem is that the circuit only works when I connect oscilloscope probes between node-A and the ground.
If I remove or decouple the probe-ground from the ...
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Why is my oscilloscope math mode showing an RMS voltage in gigavolts (unexpectedly high value)
I'm experiencing an issue with my Rigol DS1202 oscilloscope. When using the math function to measure the RMS voltage of the difference between two channels (A - B), the RMS value is displayed in ...
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Can differential probes be used with floating oscilloscopes, such as handheld/tablet scopes?
I am in the market for a differential probe (and possibly a handheld oscilloscope down the track for field work). One seller I came across has a warning for many of the probes that they sell saying &...
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Two-point probe volume resistance how to measure without guard?
So I have measured the surface resistance of a highly insulative material using a Megger MIT 420/2 and a two-point probe. But how would I go about measuring volume resistance? The Megger has no guard ...
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What type of probes are used to connect to plated-through-holes without soldering a pin into the socket? [duplicate]
Are there probes that are designed to insert snugly into 40-mil holes (about the size of those needed by a DuPont connector)?
I am thinking of something that looks like a banana plug with springs on ...
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My sourcemeter lets me do a four probe connection using banana connectors or tri-ax. What do the extra lines on the tri-ax do?
The Keithley 2450 sourcemeter has two ways you can do a 4-probe measurement: in the front there are four banana connection ports labeled SENSE HI, SENSE LO,FORCE HI, and FORCE LO. In the back, there ...
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What could be the possible reason for waveform distortion while connecting differential probe GND with single ended probe GND?
I am measuring following waveforms using a DSO:
Case 1:
Waveform 1 wrt GND using differtial probe.
Waveform 2 wrt GND using single ended probe.
Result 1: Waveform 1 distorted.
Case 2:
Waveform 1 wrt ...
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Multimeter Range and Resolution
I'm confused as to how my multimeter takes readings, especially since its not an auto-range multimeter. I have to switch to the desired range to carry out measurements. Unfortunately, the resolution ...
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Should Liquid Level Sensors be supplied AC or DC
Liquid level sensors often use two probes, when the resistance between those two probes changes with reference to the level of the liquid between them, that change is resistance is read as change in ...
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How to debug a STM32 MCU Discovery board at higher rates?
I have a STM32H735G-DK Discovery board, and can debug it with gdb (or vscode and cortex-debug). However, it is very slow - hitting s in gdb can take several ...
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Z0 (resistive) high bandwidth, probe design
I plan to make a high-speed resistive probe according to the book "High-speed digital design: A Handbook of Black Magic". There is one thing I don't understand there:
Why this probe (unlike ...
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Why are there (almost) no current shunt probes?
Most of the current probes for osciloscopes I can find are somehow magnetically coupled and have a high isolation and price.
However, in PCB design shunt resistors are often used.
Why does one not ...
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Why is the frequency response from my 1X and 10X probe seem to be converging with increasing frequency?
I'm a Mechanical Engineer trying to get into electronics so please excuse my lack of understanding.
I'm feeding a 5.0 Vpp sine wave into my SDS 1202X-E scope from my signal generator (see image below)....
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How can I check continuity longer than my probes?
I'm trying to sleuth out a wrongly wired connection on a small injection molding machine. I'm starting by verifying the connections match the diagrams from the manufacturer. However, some of the ...
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Constructing a redox probe using an Arduino
I'm trying to design an ORP that can be used to measure the total voltage of a solution. This solution would be a NaCl solution that's mixed with water that can be anywhere from 0 to 5000 ppm of NaCl.
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Difference in voltage level using different probes [closed]
I have used an active probe and a passive probe to do the same measurement at the same site. However, the active probe has measured a lower voltage than the passive probe under DC coupling measurement....
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How should I store my oscilloscope and probes
What are the best practices for storing an oscilloscope and probes?
Should the probes be disconnected after use, etc.?
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Oscilloscope probe attenuation setting
I am trying to use a differential probe that has attenuation setting of 50X and 500X. However, my oscilloscope only has 1X, 10X, 100X, and 1000X. Would it cause any issue if there's a mismatch between ...
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Sampling 24V one wire serial with a voltage divider?
I would like to sample 24V one wire serial with a voltage divider, wouldn't grounding the resistors in series potentially affect the data being transmitted?
I was considering using an optocoupler but ...
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Trying to get a replacement set of probes for an old multimeter
Summary:
I am looking for the correct terminology to describe probes from an obsolete multimeter so that I can use this information to find replacements myself.
I am not asking for specific ...
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How are 500 MHz standard passive probes tested?
I would like to understand how a standard passive probe is said to have a bandwidth equal to 500 MHz. Actually what is the standard setup to qualify a passive probe?
I found an article on Teledyne ...
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What is the difference between a differential probe isolated and a differential probe non isolated?
The classical differential probe are non isolated. But it also exist differential probe that are isolated.
What is the interest of isolated differential probe with respect to a non isolated ...
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E field probe or H field probe to detect
I have a board that is failing radiated EMC tests. There are narrowband spikes with 50 MHz intervals (300 MHz, 350 MHz, 400 MHz, etc.)
I believe it has something to do with a clock (I suspect so since ...
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Measurement with High Voltage Differential Probe
I am doing a measurement with this a 100 MHz high voltage differential probe with voltage derating. As per datasheet of TT-SI 9110 probe, the derating curve looks like below.
What impact this voltage ...
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What is the probe comp signal on a Keysight DSOX2004A?
I was trying to measure a WS2812 signal on my Keysight DSOX2004A oscilloscope. The signal didn't look right for one probe. The rectangular signal looked undercompensated. Sure enough, I know that ...
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How to extract parasitic capacitance of an oscilloscope?
Can someone please explain the procedure to extract the parasitic capacitance of an oscilloscope? I have seen that the contribution of probe capacitance is 3.9 pF. The scope is a Tektronix 3 series ...
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What is the common-mode range vs the differential-mode range of a differential probe?
A differential probe has a differential-mode range of 5000 Vrms and a common-mode range of 2500 Vrms for its input voltage.
What does that mean, and what are the differences between common-mode vs ...
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Unknown interference between signal generator, oscilloscope, and op-amp
simulate this circuit – Schematic created using CircuitLab
I am new to hardware experiments, although I have acceptable theoretical knowledge. My setup is:
a signal generator
a breadboard with ...
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Is it possible to measure 10/100baseT with a regular oscilloscope probe?
I want to measure the waveforms of ethernet signals (both RX and TX at the same time) using the DSO-X 1024G oscilloscope (200 MHz, 1 GS/s, 4 channels).
My plan is to connect 2 oscilloscope probes ...
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A budget oscilloscope for power consumption measurements of PCB [closed]
I'm working on an IoT project based on BLE (2.4 GHz) and SoC: nRf52832, and at this point, I need to do some power consumption measurements.
After going through some previously built similar projects, ...
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Homemade high-voltage probe not dividing the voltage by proper amount
I have tried to build a homemade high-voltage probe, as commercial ones are too expensive.
Firstly, I connected a 1 MΩ resistor to a ~1.4 V battery which gave an output voltage of ~0.2 V. By using ...
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Why am I seeing a signal on a shorted differential probe?
I am chasing the cause of some weird microcontroller resetting behaviour in a prototype robot. As part of the debugging, I decided to look at the stability of the power supply for the MCU.
I soldered ...
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H - probe design in cylinder cavity
I give both a short description and a longer one below. Any advice on how to design two H-probes system in a cyinder is welcome and many thanks :)
Short description
Problem: I wish to disign where to ...
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Analog oscilloscope trouble
I recently purchased an old HP 130B oscilloscope. While I have experience with old analog oscilloscopes, I have run into an issue with this particular model and before I break anything breaking into ...
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Can the 80K-15 high-voltage probe tip be unscrewed?
Can the tip of the 80K-15 high-voltage probe (that I consider buying) be unscrewed? The datasheet does not say anything about this. I would like to unscrew the tip and make another one that can be ...
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Best way to detect high-impedance state
I want to build a logic probe. What is the best solution to detect a high-impedance state?
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Error measuring Vpp using my new Micsig oscilloscope
I have Micsig STO1104C oscilloscope. I was measuring Vpp and the generator was set at 1 V, but my Micsig said it was 1.3xx Vpp. So I measured it with my KEITHLEY DMM6500 and it was measuring 1 Vpp. So ...
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Non-zero voltage measured across shorted positive and negative differential probes tied to a single circuit node
If I place the positive and negative probe tips of a differential probe on the same location, and therefore the same node, (such as sharing a test point), I would expect to read a zero voltage.
What ...
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Why there is a need to trigger to see Crystal frequency with persistent screen ? Why can't continuous run mode of scope does the overlap correctly?
Thanks Guys. I think I did not explain my question correctly. Getting dumb day by day. I am probing SMD 25MHz XO output with 500MHz probe. When my Scope is in continuous run mode, I see my persistent ...
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My Wien bridge oscillator doesn't work, what could the problem be?
I suspect I am making a probe connection mistake, but couldn't figure it out.
The circuit works fine in LTSpice but I don't get anything in a real experiment.
What might be the problem?
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How to probe UART pins of a phone?
I'm gonna try to probe this phone for UART pins: https://www.youtube.com/watch?v=scsAlvMie1M
I have a cheap logic analyzer and just bought really pointy probing pins (waiting to arrive), I also have ...
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How does a CAT 4 radio detector work in passive mode?
According to
https://www.radiodetection.com/sites/default/files/Theory-Buried-pipe-manual-V10.pdf
in passive mode a CAT 4 radio detector 'looks' for harmonics produced on the 50/60Hz mains buried ...
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Total impedance of scope probe
I would like to measure the total impedance of the scope + 20:1 attenuator + x1 probe
EDIT: Circuit modified according to Bruce Abbott's recommendation
My scope's input impedance is : 1 MΩ ±1%, in ...
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What is this oscilloscope accessory?
I have access to a FLUKE 190-504 SCOPEMETER oscilloscope. The following picture shows one of its probes.
I don't know the circled accessory in the above picture. I ...
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I am having trouble measuring the amplitude of a 97 MHz signal with an oscilloscope with a bandwidth of 100 MHz
First, I designed a Colpitts oscillator with a frequency of around 94-97 MHz. I added a common emitter amplifier to the design to increase the output amplitude of the oscillator, then I connected the ...
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Oscilloscope "isolated" inputs
As I don't want to see my oscilloscope go up in flames when I play with probing circuits, I was wondering the following:
First off, my goal is to measure different floating voltages aka the "GND&...
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Test/programming rig with spring-loaded probes/connectors
I have ESP32-CAM module with two rows of 0.1" male pins. The pins are 0.22" high. Here is a picture:
I would like to trim them, so they are too short to mate with the corresponding female ...
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