The tag has no usage guidance.

learn more… | top users | synonyms

0
votes
2answers
37 views

Connecting AC analog amps meter

I'm a hobbyist/newby and I buy some items to build a cheap nichrome wire heater.First I buy a 50feet of 22gauges nichrome wire. For 120V AC source , I need 8feet of this nichrome wire to get desired ...
0
votes
0answers
30 views

Capacitor ESR meter IC

G'day All I am working on building an ESR meter for testing capacitors in circuit. I figure I need a circuit capable of generating at least 200kHz. Looking around I found the Exar XR2206 which ...
0
votes
2answers
227 views

Can I use 2n2222 transistor instead of c9013 transistor in a vu meter?

I am building a science project for my friend. We chose to make a VU Meter. I am planning to make the Vu Meter as the schematic in the image: The audio source will be 3.5mm jack output of a ...
1
vote
2answers
204 views

How to measure current with an analog multimeter? [closed]

I need measuring the current through a dc motor with an analog multimeter, but I don't know how to select the correct function to that. The meter is a FT-360TR. I know it can measure currents of ...
1
vote
1answer
241 views

Water conductivity measurement AC, interfacing with arduino

I want to implementate this device, mentioned in the title. The problem is how to correctly build the " read out device" that is clearly a wheatsone bridge? But in AC, the problem is the signal ...
0
votes
1answer
52 views

LM3914 4S lithium polymer meter

I need help creating an LM3914 voltage meter (in bar mode). I looked at the datasheet and understand how to create a standard voltmeter (0-5V for example). However, what I need is an expanded range ...
0
votes
0answers
90 views

how work this flow meter

As you know , The principle of operation for the magnetic flow meter is based on the Faraday’s Law of Electromagnetic Induction.An electrical current (I) is applied to a coil package inside the flow ...
1
vote
0answers
56 views

How do you measure an output designed for a moving coil meter, using an Arduino?

I have a Yaesu FT-857 Amateur Radio transceiver which has an output for an Analogue Moving Coil meter. The radio will output a current varying between zero and 1 milliamp (0–1mA), depending on the ...
1
vote
1answer
156 views

Tactics for stable unity-gain op-amp

The circuit given below is typical pH meter op-amp circuit. But here LMC6001 is not configured as unity gain. My question is this, I want to make this circuit with unity-gain buffer op-amp. What ...
1
vote
0answers
39 views

How to calibrate pico-ammeter votage bias?

I'm using Keithley 6487 pico-ammeter. It's strange when I turn on the machine without connecting any circuit, there exists 0.05 Volts difference between the in and out probe. So I have to add -0.05 ...
0
votes
1answer
90 views

OSI Model for Smart Meters

Seeing as smart meters are becoming more and more popular (in particular countries), I would like to understand smart meters and thought knowing the OSI Model would be a good place to start. I already ...
0
votes
1answer
489 views

LM3915 VU Meter Not working properly

I built a LM3915 (Waiting for LM3916 to arrive) VU Meter based on Sparkfun's tutorial https://learn.sparkfun.com/tutorials/dotbar-display-driver-hookup-guide Problem is, when I plug the power, only ...
0
votes
2answers
117 views

Why monitoring power and energy in energy usage meters?

This time my question about the how power companies monitor usage. We get electric usage bill in [Kilo watt hour]/Energy. What should be looked up on for monitoring the usage the instantaneous energy ...
3
votes
3answers
210 views

Using step-up converter in metering instrument?

I am designing a pressure calibrator (my first Real project), which is supposed to measure from 0-200.00 mmWC (20000 counts) using Silabs C8051F350 (inbuilt 24-bit Sigma delta ADC). Sensor used is a ...
3
votes
2answers
439 views

How can I extend the ammeter wires to my shunt?

Is it possible for me to locate my ammeter and shunt a few meters away from each other (more than intended by original wiring)? The extra wiring obviously has a resistance and provokes a false ...
0
votes
1answer
85 views

What is the wavelength of an Itron C1S IR LED?

I'm trying to find an appropriate IR Phototransistor for an Itron Centron C1S Meter. But I can't figure out exactly what is the wavelength of the IR transistor used by Itron. Do meters have standard ...
1
vote
1answer
231 views

How would you go about creating a lux meter for very low light (0.0001 to 1 lux)?

I like to take pictures of the the sky in really dark places like Death Valley. To get an estimate of exposure times for the foreground I would like to measure the light intensity. According to ...
1
vote
2answers
307 views

Serial Data Input through Microcontroller to Output Voltage

I am new here and new to programming, so I thought maybe some of you might be able to help me in the right direction. I am looking to design a circuit that receives serial data from an RS232 port on ...
-4
votes
1answer
198 views

Smart meters and filtering [closed]

My mother suffers from Electromagnetic hypersensitivity and her electricity provider recently installed her a HF Smart Meter (CERM 1). I've been researching about ways of filtering the dirty power ...
1
vote
2answers
350 views

Can I use Mic to input Frequency Meter circuit?

Í'm new to application level of electronics that I'm studying.I have a project to do in college and I was thinking to do a Frequency Meter circuit that can measure the frequency of given input signal ...
1
vote
1answer
282 views

How can I detect brain waves

I want to build some type of electrical circuit to detect alpha, beta , theta etc. waves from the brain and maybe even show the frequency in hertz . Or at first, generate a higher power wave for my ...
0
votes
2answers
385 views

Frequency Selective Voltmeters

Does anyone here know of any cheap-ish handheld meters that are capable of measuring the voltage at specific audio frequencies? I'm dealing with a few constant frequency signals on the same wire - ...
2
votes
2answers
115 views

Is there any such thing as a linear panel meter?

I like to use regular panel meters for showing data. I would like to know if there's such a thing as a linear meter, say 10 cm long or so. By linear I mean that the indicator moves up some scale in a ...
-8
votes
1answer
182 views

Voltage/resistors/series/impedance/meter

Assume you measure a power supply voltage through a series 1M OHM resistor and observe that is drops by 1/2 its former value when no resistor is in series. What is the input impedance of the meter? ...
1
vote
3answers
702 views

How do I hijack a reading from the circuit of my digital meter

I have a tri - meter (ph, ppm, temp) that reads and displays readings on three LCD screens. I'm trying to hijack the measurement at some point in the circuit and read it in through on of the inputs on ...
2
votes
3answers
2k views

How to light an LED when a voltage hits a certain point

Lets say I need an LED to indicate when a DC voltage reaches 5 volts or more. I don't want the LED to be dim when it is at 4.5 or anything. I just want it to be full bright at 5, 0 bright at anything ...