Electronics Definition and 631 Threads

Hey I am trying to learn how waves move in time and I am not sure how to solve the following question. Can someone please guide me through it.

I know how to calculate the power output and input by analyzing the current in put and output with multimeters and using the formula P=VI. But P_out is obviously incomparably smaller than P_in so the efficiency would suck this way. Is there a better way to do this??

I am given that all the BJTs are the same. First of all, when finding node voltages like Vref should I make the node voltage a voltage source first and then do circuit analysis? If so then I would use KVL but that does not give me Vref = 2Vbe. I do know that Vref = Vb1 = Vb2. What am I doing...

Hello everybody. Its Pedro Garcia from morocco casablanca. I am mainly here to deepen my knowledge in electronics applied mathematics. I have downloaded two books , first is intermediate algebra to review my knowledge in maths in general in order to easily read the second book which is...

This is more of a consumer question from someone who knows nothing about electronics: Last night my old Amazon Fire TV device apparently died, but after leaving it in the fridge all day it's now working again. What happened?

So if I have a source of 5V and 20 amp then the maximum power I can get from the source will be: $$ P_{max} = 5*20 = 100W$$ but my load can only take in 5 watts, it will blow up. But, does this have to happen or does my load only take what current it needs? My guess is that the load takes in...

Summary:: I am a student and i plan to study electrical electronics but i don't know how to go about it.Anyone who is into it can you please guide me on how to become one I am a student and i plan to study electrical electronics but i don't know how to go about it.Anyone who is into it can you...

I have actually already written out and solved for my own solutions to these problems, but I was wondering if I could get a second opinion on my solutions: For Problem 3: For Problem 4:

Homework Statement:: How can I determine whether my basic circuit will work? A battery and two light sources. Homework Equations:: conceptual question, use basic ohms law, current law, voltage law, etc. This is not a homework question, i am just trying to understand electronics better. I am...

Hello, I am a student in mechanical engineering and also like electronics ( repairs and things like that ),i know electronics and how to build circuits,even embedded systems,but have no clue how to repair a circuit. I thought it'd be easy,but I soon found out that trying to fix pcbs isn't a...

Hello everyone, I am in an upper division undergraduate electronics and circuits class right now and the textbook that were using (Eggleston: basic electronics for scientists and engineers) is not resonating with me. I was wondering if anyone had recommendations for a textbook that explains...

Hello, Anybody have any good sources of mixed up old electrical components? For example: an old drawer full of mixed up resistors and capacitors; wax caps and jumbled up stuff? I have a HUGE jar that I am trying to fill up with this type of thing for my lab and was just wondering if anybody...

Summary: Facing a circuit with 2 parallel resistors and 2 current sources (1 dependent, 1 independent). Trying to find the current, voltage, power delivered by the independent current source and power delivered by the dependent current source. I'm trying to start by finding the current i0 but...

I am doing an experiment in electronics with AC RLC circuits, But there are a few things about what I need to do that I don't understand. First: While I know in the circuit diagram we include the internal resistance of the Inductor in series, but I don't know why we include it in series rather...

I've been given this question for my TMA2, I've tried looking at the learning material but it gives no information on how to calculate the gap? Does anyone have a formula for this? Or can someone point me in the right direction? Thanks

I am preparing a presentation on TW and have reviewed the NASA site which is good, but most of the data is at least 10 years old. Does anyone have any current data on TW mitigation? Here is the NASA link I used ►► https://nepp.nasa.gov/whisker/ Thanks, Ray

Summary: How do you determine the armature current during the braking time? For a simple permanent magnet DC motor with a known resistance and inductance in series with the armature, I would like to know how to determine the armature current if there was an electronic motor drive controlling...

Hi. This is my first post. Thanks to all who give it a look. I am working on an application that has very stringent power output requirements. There is a rechargeable battery that I am trying to manage through a bi-directional boost/buck converter as is typical of many modern-day electric...

The problem: My attempt:

Summary: Please does anyone has a lecture note dat explain solid state electronic I need a lecture note or a textbook dat explain solid state electronic especially band gap Crystal growth Diffusion of semiconductor Fermini level

I have 3 555 timers. They don't always produce pulse. Sometimes They do. Sometimes they don't. Why don't they always produce pulses? I use electrolytic capacitors. There is nothing connected to the 5th pin.

I'm finishing up physics 2(intro E&M) at my college, and I'd like to apply the concepts I learned in it over the summer. I was considering working through an electronics book, or building a radio, etc. What kind of projects or books do you recommend to cement some of the topics I learned in a...

Good evening, it's been a while since my last thread here in PF. I will go straight to the point: I want to measure temperature using an NTC3950 thermistor. My circuit diagram is as follows: It's basically a voltage divider. By varying the temperature acting upon the thermistor the output...

If we define Q factor as 2*pi* energy stored/ energy dissipated per cycle, what's the physical insight behind obtaining low phase noise for oscillators when we have high Q factors? (I know the mathematical derivation based on finding the frequency profile of an oscillator (like LC oscillator)...

This is an inverting amplifier incorporating an ideal op-amp with infinite open loop gain. I have a simple question concerning the derivation of its gain (-R2/R1). The point I circled is at 0V (Virtual Earth) but then, if V+=V-, Shouldn't Vout=0 regardless of what R2 and R1 are?? What's wrong in...

In my assignment question, the length L and radius r is given and asked to find out how the Temperature of a thin bulb filament which depends on those two parameters. and the answer is r^(1/4)*L^(-1/2). I can't figure out how. Which relation is involved?

I am working in telecom company and they told me that they installed new system and then they told me the equipment will be EOS (End of Service) after 5 years. I was wondering that how the electronics equipment's age is calculated. If I strictly categorize my questions and explain the confusion...

Homework Statement So I need to find the equivalent resistance for the following RC circuit to calculate the time constant, but I got stuck in terms of finding out the equivalent resistance. Homework Equations V = IR The Attempt at a Solution So the thing I am not sure on is how do you...

Do they have to know advanced math to design and construct circuits? What kind of math goes into design and construction of a circuit? Can you let the software simulation take care of that? Do you really need to know the voltage across a capacitor? How about the time constant of an RL Circuit or...

I have currently only worked on resistor networks and gaining the skills to analyze them. I am now beginning to learn about RL, RC and RLC circuits and still I don't think this is enough knowledge to create my own circuits. To create a circuit you must have a function in mind as in "what do I...

Hello, I've got a voltage comparator, well only on schematics, I need to chose one and I need some help interpreting datasheet. The datasheet I was looking at is of a lm393. My input voltage ranges from -7.8V to +7.8V. The datasheet says -0.3 to something. So it's not usable, right? I was also...

Hello, I am designing a circuit which basically takes two voltages (V1,V2) and based upon which one of the two is greater, turns corresponding LED. So, I have got to the part where I have output from differential op amp that is the input of the inverting voltage comparator with hysteresis...

i want to understand what's the advantage of using a voltage follower

Can you guys send me the link to the website to buy the 50v 220uf capacitor and 1/4w 30k ohm resistor? Since radio shack went out, its harder to find electronic component stores in my area Thanks

Hi, I have an old system that outputs a stereo audio signal (using Left and Right RCA audio cables). However for some reason this system is also outputting a high-frequency noise on both channels regardless of its operation. At this point I think it would be simpler to build a simple audio...

Homework Statement I have 4 resistive sensors thus I need to tie 4 floating current sources. Floating current source will give me output voltage linear to the resistance of a sensor. I know it is not the best solution but it is good enough. Image provided: Homework Equations None The Attempt...

Hello, Does anyone know of a science forum that deals with far out, controversial theories & ideas? This would be similar to the science fiction forum here at PF but may even be more outlandish, however postings would receive serious consideration. I have made some simple animations that I...

Hello, I don't know much about logic gates and how they work. I was wondering if this (Image) can work. (Is something like this possible?) The idea is that if we have logic 1, AND gate gives 1 while NOR gives 0. And vice versa.

I'm having trouble understanding how voltage drops. My understanding of voltage is a difference in potential, with potential being how much work is necessary to move a test charge to a specific orientation. So, if we have a circuit with say, a 12V battery and a 1 ohm resistor, and I had a +1...

Hello everyone ! At High School I have to make a little robot which is steerable with light. It has 2 photoresistors, if a photoresistor received light it switches on a motor. That allows us to go leftward or rightward. But, I have a problem. I don't manage to link every components between us...

Hello people. I recently finished studying mechatronics engineering. I decided to pursue this degree as I wanted to learn about many areas of engineering. When I chose this degree I just could not make up my mind on which side of engineering to follow so I attempted to go after everything. At...

Homework Statement Figure shows a 50 Hz, high-voltage, transmission line. The relationships between the sending and receiving end voltages and currents are given by the complex ABCD equations: where 'S' stands for sending-end and 'R' stands for receiving-end (a) Given the parameter...

Hello, I'm currently getting my degree in mechanical engineering but have lately taken an interest in electronics. I've ordered several books and have learned a ton about resistors, capacitors, transistors, diodes, etc. However, every circuit I have made so far has been one that somebody else...

Homework Statement I've got the following Circuit: And I have to make it in Spice. 2. The attempt at a solution So far I've got: Circuit Of Ex1 *Circuit Topology V1 1 0 dc 10 R1 1 2 4.7k R2 2 0 4.7k V2 2 0 ac 5 *Types Of Analysis .dc lin 500 100 10k *Output Statements .probe *Termination...

<< Mentor Note -- Thread moved to the EE forum >> Hi, I'm new here and maybe this is the best section where I could need help :) I've been interested in electronics lately (not schooling anymore, more on self-study, but I'm not that smart, just a dedicated one and i can't understand everything...

Homework Statement Homework EquationsThe Attempt at a Solution I know what the transients should generally look like, the only part that's throwing me off is how to model the intended load voltage of 18V. I'm guessing that when the switch is on (after transients) the load voltage will be close...

Homework Statement Hello, I am trying to Calculate The Resistance Rf and the value of the Voltage V2. The setup is a logarithmic Op amp connected to a differential Op amp. Both Op amps obey the Golden Rules. Attached below is my attempt at the solution and the question. Currently, I have an...

Im trying to do some data logging, using a raspberry pi 3 would be super easy as it has a built in WiFi and Bluetooth receiver as well as an SD card. However when the vacuum gets to about -30inHg the Pi shuts off and the red light starts flashing as if there is no OS. Temperatures arent crazy...

Hello All, I work in an optical lab and am currently attempting to determine the voltage output of a subtractor circuit I've wired up (as I'd like to work back from my output voltage and FFT magnitudes to read out the value of a magnetic field using faraday magnetometry.) So my circuit is as...

I've never been given a clean cut explanation of ground. I've heard some people refer to it as a common return path for current. Another as being a relative point that has a potential of 0V. Sometime people say Earth ground which I'm pretty sure actually means the ground of the Earth (not...