1. busevaran

    Trying to control a motor speed with a PID circuit.

    Hi everyone! I'm Buse. I'm trying to control a motor speed for a personal project. You can find the schematic of the circuit I found on a book. This circuit works with only the PID parts contrcuted. My problem start when I add the other parts. For example, U1 opamp (top left) is supposed to...
  2. Gallant74

    Circuit diagram, DIY keezer build

    Can someone help me build a circuit that is connected to a 115vac 60hz fridge compressor that runs ITC-1000f temp controller, i want to power a circuit properly with out killing the equipment I am willing to purchase any Amazon part! I have LM338t voltage regulators, I am inclined to install but...
  3. IgnacioMorac

    Protection Circuit Design for Sensor

    Hello partners The design that you are going to see next belongs to a sensor that I am building, this sensor will be capable of measuring voltages between 25-40 volts through the ADC of a microcontroller and at the same time feeding on these voltages. A fundamental part of every sensor is to...
  4. N

    S-Parameters (Cascaded system) and a few questions on RF Design. (IIP3)

    Please see attached figure for a few of the questions. I would love for the solutions to these questions. Also, what are the effects when the width of the microstrip line is increased?
  5. NYMM2346

    Suggested Re-Wiring/Testing for Ignition Coil/Spark plug of Gas Powered Tool

    Took apart this gas-powered tool to service the carburetor but wiring leading to the ignition coil/spark plug came apart. Unfortunately, the product manual doesn't show wiring connections, subcomponent is developed overseas and the company has only offerred to sell me additional parts without...
  6. W

    Joule thief circuit issue

    Hey guys, So I am making a little joule thief robot looking thing with my son. I should have done a test circuit first but for some reason when I connect the battery I get a tiny little blink and that's it until I disconnect and reconnect then a little tiny blink again. Any ideas on what the...
  7. S

    Shocked by beginner circuit kit

    I was trying to visualize a beginner circuit problem on my breadboard and I plugged in my circuit, touched a resistor and got a nasty shock. I am a cs student playing with circuits to build some logic gates so I really am a complete beginner. Why did this happen? How can I prevent this from...
  8. the machinist

    I'm getting different results with the LTspice simulation

    Hi, There was an example from my book and I wanted to build the same circuit on LTspice to test the results. However, when I create to simulate the circuit in the LTSpice environment you see below with the different outcome values. and here my ltspice results: I could not find the same voltage...
  9. Z

    Problem with transistor

    Hello, in the following image you can see a circuit with a npn transistor. I marked the given values with red and the unknown with blue. Below the circuit you can see my calculations and solutions. I'm stuck at finding I1. I would be very thankful for some guidance.
  10. mungs

    The relation between Vin and Vout (diodes circuit)

    Hi, can anyone here tell me if the function I found that relates the Vin to Vout is right? So I made a mesh analysis to find the current in the first mesh (left to right) and in the second and finally got that the Vout = (2/11)*Vi +6.328 (is it right?) threshold voltage = 0.7V
  11. thecarefulone

    Problem with Electrical Circuit Question

    Hi! I have a question related to electronics: Someone told you that there might be a problem with the electrical circuit: In addition to the standard 50Hz alternative voltage, it mights exist another disruptive frequency at 50.5Hz. For how long, at least, should you measure the voltage in the...
  12. C

    Transistor is just not working

    Hello everybody, I have a small question about transistors. I have a npn transistor (bc337). I have 5Volts on the emitter from an arduino. The base goes to a resistor (1k) and then to ground. The collector goes to a resistor (330) and then through a LED to ground. As far as I understood the...
  13. NAND4011

    Potentiometer circuit to DC-Dimmer circuit: 3 wire to 4 wire connection?

    Looking for a plausible solution to the following problem: Background: 1. Currently - simple potentiometer (linear, 100k Ohm) control that controls an AC motor 2. Motor has a dedicated DC control circuit embedded with the following possible control connection points a). "Low Voltage +10V...
  14. N

    Induction Heater- lower power application

    Hello, I am trying to make a backup induction heater that will heat up a stainless steel cell (2in diameter by 5in length cylinder, approx. 5lbs). I need to heat it to 100 degrees Celsius, controlled externally by a thermometer so no circuitry needed from temp control (unit will be manually...
  15. Dimbel36

    IGBT Gate Driver Selection

    Hello, I'm designing a resistive load bank. Currently, I am designing the switch that will be controlled by a control signal via Arduino uno rev 3. The bidirectional switch is composed of two back-to-back igbts connected by their emitters with anti-parallel diodes. (Due to cost, there are two...
  16. G

    Nand circuit, placement of resistor.

    Hey everyone, I'm new here and also a newbie who is teaching himself. I have one question: How come if i put resistor R1 before the output, the output is always 1? Even if A and B have an input signal.
  17. K

    SMD Capacitor selection

    Hello everyone, How can we calculate the voltage rating of an SMD ceramic capacitor. Is it dependent on the package size?.
  18. hungry

    LTspice ECG

    Hello. Thank you for clicking on my article. I'm from Korea and a college student. I'd like to find a solution. My circuit simulation speed is too slow. So I want to speed up. I saw what other people did at Google and made it. I want to speed up the simulation. I'd appreciate your help.
  19. P

    0 to 9, 9 to 0 counter

    Hi there, got a serious problem about Counters. i have to create "a circuit that counts from 0 to 9 then from 9 to 0 using two separate counters" and "must consider BUS concept". i used two 74192 and two 74153 Multiplexers ( for BUS ), one of the counters is ascending and another one is...