# All Questions

120,756 questions
Filter by
Sorted by
Tagged with
27 views

### What are the covers behind the terminals for in lead-acid batteries?

Some lead-acid batteries have two extra covers behind the terminals (See the images below). I understand that the 6 holes in the row in front of the terminals are used to water the cells. But what is ...
18 views

### Poles and Zeros of a Transfer Function

I am trying to understand the physical meaning of poles and zeros of a transfer function. Can someone help me how to understand the Figure 2b in the link below? What does the height of the cone ...
8 views

### AC resistance of LVAC transmission line

I'm currently working on a project to determine the transmission losses in an LVAC line as part of an off-grid distributed generation system. The manufacturer of the cable has given me a DC ...
38 views

### Pass USB 3.0 connection through D-SUB connector

I need to pass a USB cable through a vacuum chamber wall, for which we have only D-SUB passthrough flanges available. So I cut a USB cable in half and soldered a D-SUB connector to each half. For USB ...
27 views

### I2C setting MCU as both slave and master at the same time

Hello everyone I'm working on a new project with the TI MSP432P401R microcontroller. I want to have 2 separate I2C buses. I2C bus 1 will set the MCU as the master, whereas the DAC and the pressure ...
15 views

### Motor controller oscilations with flyback diodes

Have some motor controller oscillations with flyback diodes when they were added to the build. They emerge with higher rates of signal amount making by controller. So there is a need to reduce the ...
14 views

### Repair Sound Device Mix Pre 6 battery sled [on hold]

I am using a audio recording device SOUNDEVICES Mix Pre 6 with several powering options. One of them is a battery sled, the MX L Mount for the famous SONY FP970 battery. The adapter can hold 2 and ...
43 views

### ADC Calibration - Vdd calculation

In documents and lots of online sources there is a formula as follows, $$Vdd = 3.3V * \frac{VREFINT_{CAL}}{VREFINT_{DATA}}$$ But I cannot get why CAL value is in the numerator and RAW data is in ...
34 views

### Limited Gain Op-Amp

Question: Find V2/V1 simply put: Vout/Vin, given that Voltage Gain A is limited(not infinite) and output resistance of op-amp is non zero. I simplified the following Schematic like this: At the ...
43 views

### Strange LED behavior

I encounter a strange problem when I measure the LED. Please see below picture: As you can see, I only connect 1 wire("-") of adapter and use multimeter to measure voltage drop on LED and find there ...
32 views

### Hard fault on only one of two identical STM32F405 boards

So I've made two prototypes of a new custom board with a STM32F405RG microcontroller at heart and while one of them works totally fine, after a few seconds or more I'm getting a hard fault on the ...
28 views

### Multiple Power Supplies Powering Long LED Strip - Proper Way to Ground

Please refer to the above diagram. The 2 power supplies are each placed in the opposite end of the led strip. I will be connecting the signal ground and the power ground just before it connects to ...
22 views

### Single phase appliance on 3 phase circuit

Is it possible to have a single phase socket on a 3 phase circuit? It is a 3 phase radial circuit on a 16a breaker. The last 3 phase socket on the circuit basically wants converting into a single ...
29 views

### Max startup current for Vacuum cleaner motor

We used the vacuum cleaner motor 2200W 220v in one dental device (vacuum former) as you can see here: So now one of our custumers said when they used this device the power cable is warmed and when ...
83 views

### How do you structure large embedded projects

Background: Junior R&D Electronics Engineer (Only EE in the company) - The hardware and the coding is not the problem, my biggest issue is getting a proper overview of the project, and where to ...
13 views

### Frequency Deviation is given by del (f) = KfAm (Kf= frequency modulation sensitivity and Am= Amplitude of Message signal)

Then why has it been divided by 2pi, as shown in the image. Really confused. Please help.
38 views

### Split output of one temperature sensor to two independent signals using an op amp buffer

First off I am a car guy, if I have a schematic or details I can solder what I need. I have a client that fitted a digital temperature gauge to his car, he also wants to have the gauge on the ...
56 views

### Using pointer of a function's returned value

I would like to know if there are possibilities to optimizie the following code from this: ...
35 views

### How to make lineal actuators go in both directions?(Using arduino/microcontroller)

Im Stuck Here, I want to make the lineal actuators to go up and down, both of the actuators move to the same direction at the same time. The arduino receives a signal as input and then the ouptut ...
41 views

### Can heavy processes running in background cause lag in arduino's serial port communication with a computer?

I have a Ubuntu 16.04 machine talking to a Uno board. This arduino board is sending 100 chars of line at baud rate of 115200 as fast as possible. Usually I get a line every 7ms to 10 ms (I am going to ...
74 views

### I need help reading resistors

I've been using the arduino starter kit recently, and for a project I require a 10 thousand ohm resistor. The kit comes with a belt of different resistors, and It has some 10k resistors but I've been ...
34 views

### Need help with choosing the right pre-amplifier for my rural base station design

I am in the process of designing a multi radio base station for a FWA application. The distance from the main base station to the terminating units is a 1 KM. I have 2 sectors and am planning to use ...
111 views

### 16 A appliance into 30 A outlet

I am hoping someone with electrical system knowledge can help clear something up for me. I am considering purchasing an appliance the requires a 230V, 16A outlet. I asked an electrician about wiring ...
68 views

### Can someone explain to me the difference between these two wiring configurations?

I am trying to connect a combined pressure transducer and temperature indicator to a DAQ system by Dewesoft and this sensor has two available wiring configurations available, 3 wire and 4 wire. I'm ...
72 views

### Waveforms from a Function Generator, What is Good Enough?

I got an HP3311A function generator. The Sine wave forms below looks pretty bad to my eyes. Is it normal?
36 views

### Imversely proportional current controlled voltage source

I need a circuit that senses a current and outputs a voltage, but in inverse proportion. In my case: When the current is around 0A, the voltage source should be around 18V (my Vcc). And when the ...
563 views

### Super Regeneration Detector

This is a circuit for a remote control toy receiver. Can someone help me understand this. Connecting the antennae to the collector makes no sense to me. RF is my weakness. Datasheet where this came ...
61 views

### are there round header pins

I am attempting to get two probes through a sealed case to detect the PH of a fluid of water. my though was to get two header pins and seal them with a custom 2mm diameter seal. However it looks ...
40 views

### How do pixels in a LCD display are individually controlled by a electrode?

How do tiny subpixels in the Led displays are controlled by those indium tin oxide electrode.How do they provide different voltage for each pixel
81 views

### Does resistance decrease over a resistor?

If ohms law pertains to voltage, current, resistance across a resistor, in order for voltage to drop, and current to remain the same, does resistance drop as well across the resistor? To explain what ...
54 views

### Making my old radio smart [on hold]

I got an old radio for free from an acquaintance, which is not working anymore. I want to make the radio 'smart' by connecting it to a chromecast audio. I am a software developer and and know almost ...
29 views

### Relationship between base resistor and collector current in this unbalanced differential amplifier

For this BJT circuit, I was wondering if there was a solution for how the collector currents change with respect to the value of the single base resistor. This arrangement popped up in a circuit I ...
54 views

### How to get phase shift in this task and in general?

So the task says: In the serial circuit connected to the 50 Hz frequency alternating voltage, effective voltage values 𝑈 = 220 V, known voltages 𝑈L = 660 V and 𝑈C = 500 V. The current in ...
48 views

### How does a subway travel card work? [on hold]

How does a subway travel card work? What is mechanism inside? Is it a chip? How does it save information about your balance? How is this balance changed when you swipe or tag in?
29 views

### High quasi-isolated voltage measurement

I have to measure a DC voltage and an AC voltage around 100V. I found the circuit with an AD629 and one OP177. I simulated everything in Spice and it works fine, at least in the simulation. In ...
19 views

### Power of an adapter working with different input voltages [duplicate]

I have a laptop adapter which, according to its label, works with 100-240 V, 1.8 A, 50-60 Hz as its input. Since only one input current has been mentioned, does it mean that its consuming power is ...
38 views

### I am stuck at this step C(AB+A'B')(simplify using boolean laws)

I cant figure out is AB+A'B' =1 or another answer
59 views

### Can we use both FFT and PSD to obtain a random signal's frequency domain representation?

I always encounter random noise frequency domain representation as PSD(not FFT), something like in the below plot: Without diving into math too much, practically speaking can we always use FFT ...
48 views

### Confirm transformer fault vs markings / spec

I'm trying to troubleshoot a German ceramics kiln controller from about 1989. There is a 100ma glass fuse in front of this PCB transformer that blows after a second or two when power is applied. ...
36 views

### What's the purpose of the T568A/B's color wires?

I know that pair 3 in T568A is used for transmitting data while pair 2 is used for receiving data. In T568B the logic is reverse, meaning pair 2 is for Tx and pair 3 is for Rx. What's the purpose of ...
23 views

### esp8266 reset - power consumption

I am working on project with esp8266 UC powered with 3.7v lithium ion battery, where the reset pin is pulled low to keep it OFF. I would like to know if my battery were to be consumed with this ...
36 views

### My slayer exciter circuit doesn't work properly

today I tried to make my own Tesla coil circuit according to the schematic below, except that I have changed the number of turns on the secondary and primary so could get a higher output voltage (1 to ...
32 views

### Find the exponential Fourier coefficients

I am confused as to what the periodic function, Vin, is! I know the slope is 2/pi, but what about the vertical line? I am also unsure about its relation to Vo.
15 views

### ngspice ltvspice netlist compatibility problems

This is my netlist ...
31 views

### Using USB-6210, relay, to control a 12V double solenoid valve

I am kinda new for the wiring of the relay. I have read some posts in forum regarding connecting the solenoid valve to the DAQ. But I am still not too sure how it all should be done. My objective is ...
87 views

### What's destroying the MOSFET in my buck-boost converter?

I have currently wired up this inverting buck-boost converter circuit: However, when driving the input of the TC4420 with a 62.5kHz square wave with a 40% duty cycle, the power supply overcurrent ...
43 views

### SPI Communication between ADXL345 and TM4C123GXL (TIVA C Launchpad) doesn't work as intended

I need to interface the TM4C123GH6PM based Microcontroller board TM4C123GXL (TIVA C Launchpad) with a accelerometer (ADXL345) by Adafruit. As, I am bound to use SPI communication and program on ...
53 views

### Why the current on this vector diagram have coordinates like this?

It is an example from a textbook. It is a really basic example and the purpose of the example is to show how vector diagram works. Here is the example: and this is the vector diagram: What I ...