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  1. G

    Design an 8-bit adder block that can add any two 8-bit registers from a bank of 10 registers and store the result again in any one of them.

    Hello, I am engineering student in Turkey. Our teacher gave us a homework. I took care of all but this question. But I couldn't do this question. It is very complicated, I just could not put it in my mind. Can you help me? Thank you
  2. E

    Home-made accumulator charging problem

    Hi guys, I just found old flashlight and due to inability to use any of the new batteries I decided to create new one from 4xAA batteries (NiMH aku AA;1,2V/2000mAh Panasonic "Eneloop"). I created simple circuit and used old flashlight switch in it. It works just fine. Then I added DC charging...
  3. Y

    Need help in creating a next state table from the circuit below!

    Hi Here’s the circuit that I want to find the state diagram for, but before that I need help in creating the next state table for the circuit first. pls help!
  4. T

    Question about technical limitations of 12v relay switches

    Hi, I'm new here, I've just started a project that has me building an electrical circuit for the first time and I don't really know what I'm doing! I'm hoping someone can answer a quick question. I have a 12v electric motor (has two power levels, at 9A and 20A and it was suggested to go with a...
  5. T

    Can anyone help me circuit a Tricorder?

    Hi there! I have 12x 3mm LED's: - 6x flashing - 6x static To this I have a standard slide switch and cell battery holder. My issue is this: how do I link these 14 components to one another and ensure the flashing LEDs stay flashing and the static, static? I believe that a 6V battery will...
  6. T

    PLC communication

    Research the ability of PLC's to communicate via 4-20mA and 0-10volts between the laboratory devices and the PLC This would include how to communicate between these devices using an analog device that has 0-10 volts and converts to 4-20mA.
  7. G

    Need build a circuit that flashes 4x

    Guys, I need some help. I need to build a circuit, that flashes a LED 4 times (only 4x, in a short time, like less than 1/2 second), every time that i click a bottom (click switch). If you can draw me a circuit that may work, I'll be grateful (cuz I'm still learning circuits).
  8. P

    Kirchhoff Voltage Law in a two port network

    In a tutorial about h parameters of a two port network I find the below snippet unable to grasp. According to KVL, the total voltage in a loop is the algebraic sum of the individual voltages. But why in this tutorial ( equation 1 in below image ) it's given so. It should be something like V1 =...
  9. C

    Dependent Current Source

    Hi guys, I'm in an introductory EE class and I was wondering, if the dependent variable of a dependent current source is zero, does the dependent current source become a short circuit or open circuit? Thanks for the help.
  10. C

    Voltage Division Question

    Hi guys, I'm working on a problem here where I believe one of the steps uses voltage division to find the voltage across the 10ohm resistor. However, that's not how the solution found the voltage across the 10ohm resistor. I was trying to find the voltage across the 40ohm resistor first and...
  11. C

    AC Integrator with Square Wave Input

    Hi guys, I am currently working with an AC Integrator and have a square wave as my input while my output is a triangular wave. I am confused why the triangular wave has a decreasing slope when the square wave is at +4V. I believe it has something to do with the area under the square wave...
  12. electrolives

    Electric Solar Converter

    I want to understand what is the reason for this circuit and each part of it? Can you explain this?
  13. A

    Any available circuit diagrams of good basic walkie talkie licence free India

    Hello all I wanted a basic and good circuit diagram for walkie talkie that can be designed and made into ready use.Have attached image.Thanks all
  14. Clarkdale44

    Relay timer 2 min on and 10 min off, and repeat constantly.

    Hello I want to make an auto relay timer circuit such that it turns on the load connected to the relay for 2 min then turns off for 10 min and repeats this cycle indefinitely. I have a few 555 timer lying around was hoping if could make something out of it. The timings doesn't needs to be...
  15. Â

    Transient circuit

    My college professor asked us to take a real life problem/device and design and solve its circuit using transient response and Laplace transforms. It has to be a simple circuit, maybe just some capacitors, power source, switch and resistors... My biggest problem is finding a connection to a real...
  16. J

    Subthreshold Transconductance Amplifier Design

    As part of a broader project, I am designing IC circuit using CMOS to one of the first steps I'm working on is the filtering a series of pulses with of the noise. The actual pulses are around 1 kHz so I am implementing 2nd order sallen-key high pass filter. Since the capacitance is limited to...
  17. A

    what's the working principle of this inverter circuit

    https://imgur.com/a/yCI0j I found this inverter circuit online I can't read it , can you explain it to me thanks
  18. sr13579

    How am I supposed to get a plot from this code on WeSpice(NGspice) engine?

    There is the code ’npn transistor vbias 3 0 dc 5v vs 1 0 dc 0v rb 1 2 20k rc 3 4 2k q 4 2 0 mynpn .model mynpn npn (BF=175 IS=1e-17 VA=75 BR=2) .dc vs 0 5 0.5 .plot dc v(3) -i(vbias) .end ’ But the output is showing a negative going down. How to get the graph of the plot with this app called...
  19. sr13579

    Can't get a print of voltages between nodes from this SPICE (NGSPICE) simulator.

    The code is here, Diode Voltage Drop r1 1 2 10k r2 2 3 5k r3 3 4 4k r4 4 0 3k vin 1 0 dc 10 .print dc v(3,2) .end As you can see I am trying to get a voltage drop between node 3 aand 2. But the print function is not working properly. It is just showing the usual outputs of( the ouput is...
  20. L

    How can I connect my circuit to power?

    I am trying to build an escape room puzzle, where someone holds a key fob up to a sensor and a maglock opens, and I went online to buy something that I assumed was ready-in-box but instead they sent me the photo attached which I'm 99% sure was originally a car immobilizer and is now being used...
  21. T

    How to calculate value of a Resistor for a Circuit ?

    Simple LED circuit doubt. Assume : I have a LED with forward voltage of 3.0 V and forward Current of 350mA. With 9V battery, i would be calculating the required Resistance with the Ohms law : R = ( Source Voltage - Forward Voltage) / Forward Current. Here we dont consider the Current Ouput...
  22. obr3ptox

    Can't interprete this "adaptation circuit"

    Hello everyone, I'm working on my thesis and came to a point where I can't interprete a part of a circuit I'm using. This should be an adaptation circuit, so I am guessing it's filtering my signal in some kind of way, but cannot say with certainty which kind of filter should it be. I could say...
  23. A

    Stable DC power supply point for Ultra Low Noise Amplifier (ULNA)

    Hello good people, I need help. I'm posting a schematic of an ultra low noise amplifier. It is to be powered by batteries. For that reason, I need a stable DC solution in the place of R4 resistor. I was proposed to achieve that by using another JFET and an integrator circuit, but I am not...
  24. sr13579

    Soldering Iron troubleshootings

    Hello everyone, this is my first thread here. I am using a 60W soldering iron which has a temperature regulator on it. I have never seen anything like this. Also this iron has a ground crockodile clip which saves me from the unnecessary shocks.Also it is automated. It turns off/on all by itself...
  25. R

    Newbie trying to understand a circuit

    Hello. I am an electronics beginner. I would like to understand a circuit that is in a book from the 1980s entitled "Computer Controlled Robots", published by Usborne. May I ask here? 1. The book does not specify the exact model of relay to be used, merely that it should be within certain...

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