1. U

    Celestion A6S Search for a diagram or service manual

    The subwoofer formally works, but when the level increases, an unpleasant, inadequate sound appears. These are definitely not speakers, I checked them on another device. No body vibration. The oscilloscope shows that the final stage does not have enough power. This subwoofer uses a tracking...
  2. salhi

    Circuit to create Impulsion using JFET

    Consider the following circuit : Working in power electronics, we considered the JFET as a voltage controlled resistance, our professor said this is the equivalent circuit : Initially the transistor is blocked, thus the capacitor is charging, when v_c = v_E > v_A the JFET is conducting thus...
  3. jma2388

    LM2679-5.0 Switching Regulator Design

    I am designing a constant 5 volt output switching regulator that bucks 12 to 24 volts down to 5 volts while supporting 5 amps. It is used to boot up a Raspberry Pi with a 10 inch screen. At 12 volts, the Pi will boot up fine. At 24 volts, around halfway through the bootup, the regulator will...
  4. A

    Wondering if anyone could identify this

    I have a Samsung 60" TV Model code UA60J6200AWXXY. The problem was I plugged a multi USB power board into it and as soon as I did the TV went off and I could smell something burnt. Removed the back cover off the TV after unplugging power of course. Have found a circuit that I think is what burnt...
  5. D

    Wiring blower motor to 120v plug

    Looking for any advice how to wire this blower motor to a 120v outlet. My dad pulled it out of a pellet burner and attached an extension cord to the terminals (black wire to red terminal, white wire to white terminal, ground wire to a screw on the frame.) When he plugged it in it ran for about...
  6. solivagant56

    No power supply in laptop.

    Here's what I know so far. The AC adapter is fine, the DC jack in laptop is fine. The battery is fine as well. The issue I am facing is that the battery would stop charging in between and the system would keep switching back and forth from DC to AC and then DC again and then would finally turn...
  7. DJZ

    Leakage Current in Single Phase AC Motor

    Hi all, I have a single phase motor (115VAC 1/4hp) that keeps failing our internal leakage current test. We are measuring about 0.1mA of leakage current when the pump is plugged in, but powered off. The only thing the the live is wired into is an IEC connector then into a two-terminal SPST...
  8. C

    Looking for this male connector

    Hi, looking for the name/where I can find male plugs for this connector so the battery can be charged. Tried Powerpole connectors, they were to big and to square. Thanks for any help.
  9. HDJG

    Power management for 6 axis robotic arm

    Hello Guys, Im currently in the process of designing and then building a robotic arm. And now im designing the electronics for it. They should be pretty simple "i hope". I've attached a picture of the circuit that I am currently designing on, and maybe you notice im not an electrical engineer...
  10. S

    What is the right way to use TPS3839 for power monitoring

    I'm planning to use TPS3839 in 3.3v battery operated project. As per attached datasheet it says I will be connecting power supply for IC GND, VCC and it will activate RESET' pin when power is below the required level. Here I do not understand its working, looks like when battery is low it will...
  11. lpares12

    Help powering an MCU when a switch changes state (with auto turnoff)

    Hi! Been trying to practice electronics after a long time, and found this tutorial https://randomnerdtutorials.com/latching-power-switch-circuit-auto-power-off-circuit-esp32-esp8266-arduino/ on how to do a power latch which lets you turn off an MCU when its job is done. So to practice a bit...
  12. S

    Low frequency oscillation induced during CCPS discharge.

    Hello all, I am designing a CCPS and using a phase-shifted, series-resonant bridge as the switching topology. There is a DC block capacitor in series with the transformer primary winding. When the target voltage is reached, the H-bridge switches are turned off until a command for the next...
  13. J

    Three phase controlled rectifier for unusual battery charging application

    Hi, I'm building an engine driven generator to charge a 48V 300Ah LiFePO4 battery bank. The generator will output three phase power at 90 Vac line-to-line, 170 Hz. Electrical output power will be about 10kW at best efficiency point. I'm looking at options for how best to use this output to...
  14. D

    Help identifying these connectors and what parts should interface with them.

    These look like they would accept bullet connectors of some kind, but I can't seem to find the parts to actually look up what they interface with.
  15. S

    Battery & Power question

    Hey Guys & Gals, I have a couple questions about power for a device. I have a small handheld computer/Programmer and it has USB-C port and has a 3.7vdc lithium wired battery. The unit has the battery in the space where it could hold 4aaa batteries thou not wired for them & no contacts for them...
  16. A

    Inductor Design Problem

    An inductor of inductance 80mH, 500 A at 60 Hz needs to be designed. But my area product is coming too high. Probably because of VA rating. Due to this I can't find a suitable core that matches its Ap. Please help me with calculations of Ap. Is there something I am doing wrong? My voltage comes...
  17. Daniel28

    Emulate battery in charging state

    I am trying to build a circuit to emulate a lipo battery. Basically the circuit consists in a power supply to emulate the discharge behaviour and a variable load to eulate the charge behaviour. This is the circuit in a simplified way This basically generates 2 circuits...
  18. Ladraz

    A weird problem (Audio + Power)

    The problem: I have 3 Adams A5X studio monitors and 1 z5500 system. Let us call the Monitors A, B and C. Sometime last year (2022) Monitor (A) started to randomly cut in and out, the power button is ON however, the sound cuts off and then, at random times turns back on again (If no sound is...
  19. prof.marco

    The christmas tree circuit

    Tricky simple circuits in DC to help understand Power meaning