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  1. A

    What can of relay or system do I need to use for 7000V rat trap?

    Please forgive if some information or diagrams are missing, I will provide any information you consider necessary if you ask for it in the thread. As you might soon discover I have no background/knowledge in electrical engineering. I will start working on a project to build an electric rat...
  2. J

    Please help: TP4056 charging module output voltage

    Recently got one of those, and I was wondering what the output voltage was. I know the input is 5V, but the very-much-standart Li-ion 18650 battery I use is 3.7V I'm planning to connect a Digispark ATTINY85 board to the output, which requires also 5V. Will the ATTINY85 work properly? I heard...
  3. C

    tesla coil help , please!

    Hello I have been trying to build a tesla coil for awhile now. I cannot get a bulb to light up . I have gotton some crazy voltage readings tho. It only a 9 volt coil and this my first big project . getting really frustrated , just need a little help. Please anybody
  4. RachelAnne2020

    TPS54116QRTWTQ1 Design| VTT_DIMM and VTERTF Voltage Problem

    Hi, guys, I'm new here. Recently I made a design of TPS54116QRTWTQ1 based on the datasheet. According to my design parameters, the actual voltage CPUVCC15 is 1.5V, VTT_DIMM is 0.46V and VTTERF is 0.86V. But the voltages of VTT_DIMM and VTERTF are not correct. When I remove the load behind...
  5. D

    Missing datasheet from the new motordriver JYQD_7V.3E3 24V

    Has someone the new datasheet from the JYQD_7V.3E3 motordriver 24V (that one with the hall sensor pads on the side)? I can't find the new version or this one where the hall sensor pads aren't aligned...
  6. HappyDoggy

    I am a newcomer to the name conversion industry.

    Hello everyone, I resigned a few months ago and transfer the industry. I have already learned the basics of circuit, 8051 microcontroller, I contact proteus a few days ago, and now I am using it to make PCB. I am currently blocked on the schematic. I want DIY a learning board, it will include...
  7. J

    Protection circuit ULN2803

    Hello Everyone In this post I want to ask if you know of any circuit that can protect the integrated ULN2803, because when I make the connection to a stepper motor it overheats and stops working correctly, or I advise to use another reference to control the motor Step by Step? ULN2803 I am...
  8. 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.
  9. 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...
  10. A

    3 phase 3 wire measurement

    Dear all, I am trying to build 3 phase voltmeter that could measure L-L and L-N voltage during 3 phase 3 wire and 3 phase 4 wire connection. 3 phase 3 wire and 3 phase 4 wire connection are external connection. as we know in 3 phase 4 wire we will get neutral reference so we can get...
  11. C

    Voltage Division Question

    Hi guys, I am a total noob and just learned voltage division. I was given this circuit and was wondering why it is appropriate to apply voltage division across the 60 and 20 ohm resistors. I know they are in series which is the basis for voltage division, however the 45 ohm resistor on the...
  12. S

    Bipolar transistor

    Hello everyone, I have a little issue here. I know it's not really hard but it has been a moment since I've worked with circuits like this and transistors, so I can't figure out this circuit... The question is: In DC analysis, calculate the bipolar transistor's voltages Vb, Ve, Vc. Deduce the...
  13. electrolives

    LTSpice Current vs Voltage Graph

    How can i get current across voltage graph on LTSpice?
  14. electrolives

    LTSpice AC Signal 30sin(2pi50t)

    How can i put the Vi's values on LTSpice? 30sin(2pi50t)
  15. J

    SMD Electrolytic Capacitor: Decoding Capacitance & Voltage Rating

    I have an old accelerator board used in the PDS slot of an Apple Macintosh SE/30. The board was manufactured around 1994. I want to replace the electrolytic capacitors but I'm not sure how to decode the numbers printed on the caps. Here's a photo: As you can see the numbers are: 22 6 A...
  16. mading2018

    Half-bridge DC/DC converter

    I am trying to simulate a half-bridge DC/DC converter, and I would like to increase the output voltage to at least 320 V. Do you have some suggestion on how to do that?
  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. Clarkdale44

    Inrush current limiter... How to do it?

    Hello... I have an DC to AC inverter, which is capable of outputting 600 Watts at margin. I have a few inductive loads that causes the inverter to overload and restart (after restart the load works fine). Although it only takes 1 second approx but still it's annoying... My inverter can run all...
  19. N

    Breath Controller with 3.5mm Jack to make 0 - 5 V Variable voltage (Control Voltage) on 6.5mm Jack

    I am a beginner and wish to tackle this project... I have an old Yamaha breath controller device that has a 3.5mm Jack and requires -9v on the tip (the sleeve is positive). It draws a current of approx 7mA to 20mA depending on how hard you blow it (from what I have managed to research but may...
  20. ala khemiri

    can anyone good on mikroc can help me?

    have a a Project that measures the voltage from a 3-phase lines and Display it on LCD using PIC16F877A. I wrote the code in the mikroc language; the problem is that the LCD shows a lot of wrong characters. this are the Project code `sbit LCD_RS at RB4_bit; sbit LCD_EN at RB5_bit; sbit LCD_D4...
  21. A

    Current Sensor threshold and monitoring

    Hi all I am using the following current sensor: http://uk.farnell.com/lem/hais-400-...meResp=All&searchView=table&iscrfnonsku=false Datasheet: http://www.farnell.com/datasheets/51649.pdf?_ga=1.141388658.194281532.1473847905 I will be measuring currents in the range of 500A to -500A, and I...
  22. D

    Governor for homemade generator

    Hello, I'm new to this forum so I would like to say Hy to all. I builded homemade electric generator. It's 2kw generator from Briggs&Stratton lawn mower engine (four stroke with carburator and centrifugal governor) and 1phase inductive industrial motor. I managed to get motor to generate...
  23. Clarkdale44

    Solar charge controller ?

    Hello I have got one last confusion about charge controllers doesn't matter whether it is pwm or mppt. Thing is i have seen many CC with variety of output amps on 12v and 24v with different manufacturers... But they are all different.. Which number in a charge controller defines that how many...
  24. Clarkdale44

    Why there is an internal resistance in the batteries?

    Hello My question might seem very obvious but i never really understood why... Too much power is being wasted during charging because of this internal resistance, there must be a logical explanation for this and i need that to know. I am not looking for technical answer instead if you could...
  25. Clarkdale44

    Should i buy Watt Meter (aka killawatt) or regular Clamp on meter to determine the device wattage?

    Hello As the title says i need to know what should i buy? which one would give me the most accurate reading? I want to know how much power my appliances consumes, tv, washing machine etc.... Also i need to buy a new ups for my PC so just wants to know how much power my pc eats. I have a 500W...

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