Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [tester]

41 questions
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How does this continuity/mains tester work?

Many years ago I bought a multi-function testing screwdriver, the instruction sheet (which I have mislaid) claimed you could use it for a surprising number of tasks: Continuity of fuses Mains voltage present (barrel marked "70-240V" and, amusingly,…
RedGrittyBrick
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Can electric bulbs be powered by connecting the negative terminal to earth?

I have a very fundamental question, will an electric bulb glow with one point connected to the positive terminal of the electric line and the other point to earth? In my school some 10 years back I learnt that we are connecting the two points of the…
SpringLearner
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How do I test a USB drive to be sure it is not a “USB killer”

I have recently read of a dangerous USB drive containing a circuit instead of storage, that destroys the hardware of a computer by injecting a high voltage, high current pulse into the port it is plugged into. See this article It should be easy to…
Harry Weston
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Proper Component Testing (Specifically Resistors)

What is the best practice for testing small components such as resistors / capacitors before shipping? I buy these in bulk, and while it is easy to catch the duds that have already failed, sometimes there are components that spontaneously die in the…
MrSynAckSter
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Short circuit test on long coaxial cables

In a building infrastructure there is coaxial cables for TV. The first end of all the cables is on the roof. The second end for each cable is in different apartment. The problem is that I don't know which cable is connected to which apartment. So I…
Yousf
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What is a Reacto Tester unit and are there any projects in which I can use it?

I was given an old piece of electronics. It is a Reacto Tester made by Antronic Corp from Chicago. After a quick glance at the manual it seems that its a tester for tube display units such as television (color and black). I am wondering if there is…
KingsInnerSoul
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A question about the current value in a mains tester

After reading this question, I simulated the tester as in the below circuit along with the current passing through human body: Even I set the R_tester to zero, the current still will be around 10μA which is too small for a neon bulb. This is due…
user16307
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How do you test SMD ICs that are not soldered to a PCB?

To be more specific, let's say I have SOP16 SMD chips that have been purchased from overseas. I have several PCBs that they need to be soldered to, but I don't want to risk paying for assembly and also wasting a PCB if the chip (for whatever…
Dave
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Low volume mixed signal electronics production (hardware test, calibration, flashing) automation

I am designing a mixed-signal board with microcontroller that will need flash memory programming for its firmware, (self-)testing, and documentation for the final production steps. I know there is a whole branch of the electronics manufacturing…
handle
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How to test capacitors of non working circuit board using capacitor meter?

I bought broken sega megadrive 2 clone console. Something wrong with 7805 IC supply (I changed to another, but no result). But now I want test electrolitic capacitors and resistors, because I thing somewhere short/open circuit exits. I have chinese…
kesrut
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Voltage leak when muxing Li-ion cells for voltage measurements?

A disclaimer before I dive in, I am not working with a battery pack. Anytime I refer to Li-Ion cells or 18650s, I am trying to handle each cell as an individual. I am actually avoiding building a battery pack, that would be a problem. I am working…
Mr.Thinkage
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Alternatives to neon mains tester for home use (230v)

I've always relied on neon screwdrivers over the years and personally haven't had any issues with them. I recently bought a new one, but find that this lights up at the slightest hint of electricity (even touching it at both ends!) which I believe…
Andrew Stephens
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Simple wire continuity tester, but also needs to check shorts

I am trying to create a simple cable tester, that needs to check continuity of a multiwire cable. My first thought was to connect all wires at one end to a positive voltage, and connect LEDs at the other end. If there are 5 wires inside the cable,…
R2D2
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Neon-lamp type tester glows on gooseneck lamp adjustable shaft

I have bought several adjustable gooseneck shafts with the intent of creating lamps of my own. I have put a brand new 2x0.75mm^2 cable through it and attached a simple E27 light fixture. I have noticed, however, that when I plug the cable to the…
skinny_mike
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"Live neutral reverse" and "hot/neu reverse" difference?

I've got a "Meterk GFCI Electric Socket Tester" that can detect "live neutral reverse" and "hot/neu reverse" cases. Meterk E2752 What could be the difference between these cases? Isn't "live" a synonym of "hot"? Thanks.
Steph_P92
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