1. quadespy

    Designing a circuit that will amplify the input current on ltspice

    I want to design a circuit mechanism that will amplify the input current by 6 times. The circuit must contain at least 3 MOSFETs, 1 independent source, 1 resistor. I tried but couldn't do it on ltspice. Can someone show me the circuit on ltspice ? thanks.
  2. F

    Car side-mirror dimmer simulator circuit - DIY

    Would like to make a simple car side-mirror simulator circuit. The side mirrors I installed (for better blind spot) do not have a dimmer circuit and I am getting LIN bus errors since the dimmer wires are disconnected. Would like to DIY something that fools the car into thinking it is...
  3. J

    Choosing of resistor value at input of optocoupler (EL 817)..

    Hello all I'm trying to make a small circuit in which i have to choose the resistance value.. can someone tell me how to choose the resistor value at the input of Optocoupler IC. And my input voltage is 3.3V .. and current 25mili amps ..
  4. E

    Resistor identification assistance please..

    Hello, looking for assistance, I am used to identifying resistors by the colour code. I have a pair without colour code, these were soldered though hole in a power supply PCB for a Bang and Olufsen television. The PCB is about 8 years old and the failure seems to be commonplace at this age...
  5. J

    Identify Fusible resistor, Sole F63 2014 treadmill motor control board

    Need help identifying this component, in the motor control board for my Sole 2014 F63 treadmill. I believe it's a fusible resistor but can't tell what size or kind. Also not sure if this is the root of the original problem (see below) or just an added headache to slow me down and get me yelled...
  6. K

    Help identifying a resistor

    So I have been working on a BASH amplifier out of a Triad Silver Omnisub and have come across a resistor that I’m having a hell of a time identifying the value of. It reads at very close to 39 ohms, but from the colors of the bands on the resistor, I’m stumped as to what it’s original value...
  7. Laotzsa

    LED circuit troubleshooting

    Hello everyone. This is my first post on the forum, I am currently working on a seemingly simple circuit. I think a constant current driver is the solution; after wiring everything up last night the LED was nice and bright and circuit ran great. I decided to charge the Lipo over night, and when...
  8. MaximusPegasus

    Replacement for RWT05 15 ohm ceramic capacitor

    Hello, I have a broken Panasonic TV that has a broken three-pin RWT05 15 ohm 142 Celcius cement resistor. Not a ceramic capacitor. It's a cement resistor. I messed up in the title, sry about that. Now my question is, is there a replacement for it, or a resistor that I could use instead of that...
  9. DonBradman

    Arduino pin getting input with just a physical touch

    So I have a switch connected via two wires to a two pin plug which is supposed to go in a two pin socket. One pin of the socket goes to 5V and the other goes to a digital I/O in the Arduino + GND (via 10K). When the switch is pressed and the digital arduino pin goes high, stuff is supposed to...
  10. B

    Burning of Resistor in the Clamp Circuit of an SMPS

    This circuit has been designed and optimised. When implementing on PCB R3 resistor is burning up. Any reasons or suggestions for this to happen? Circuit is stable and safe when supplied with 190V and any higher R3 starts burning up. R3 has a power rating of 0.125W went with the parameters of PI.
  11. K

    When to use Pull-Up Resistors on read/write pins of Memory connected to the 8085

    Hi, I noticed that 4.7k ohm pull-up resistors are used in this circuit on the read/write memory pins: Saundby's MAG 85(scroll down to yellow text), but in other circuits where the read/write / io/m signals are decoded by the 74138 for example, pull-ups are not used? Is it because in the MAG 85...
  12. N

    Resistors connected to op-amps

    Hello everyone! I'm trying to solve this assignment and I'm not sure what to do with all those resistors. Should I calculate an equivalent resistance for each group? And how do the resistors connected between the terminals of the op-amps influence the circuit?
  13. Ernst Eiswürfel

    I can't seem to find this Resistor

    I have a garage door and the controller board had a few dead components that i replaced, but the only one part is difficult to find bc it's dead and i cant measure it, is this a "10 kOhm 1W" resistor or a "10 Ohm 1W" or is it a really different one?.
  14. K

    Clock edge detector using capacitor and resistor problem

    I have watched recently this video: At the end of it he describe a way to make edge detector by using capacitor and resistor. The thing is i don't see it being discharged in any way. Would't it make it impossible to charge again and in consequence make current flow through the resistor and make...
  15. MrsssSu

    TL 431a voltage regulator circuit

    Hi all, below is a TL 431a voltage regulator circuit. Just out of curiosity, what can I do to replace TL 431a with its internal discrete components circuit so that I can better understand how a voltage regulator works :) I have posted my LT Spice file below so that you can unzip and simulate it :)
  16. MrsssSu

    Discrete Half-bridge driver

    Hi readers:), I found datasheet for HALF-BRIDGE DRIVER IC here . I was hoping to find the IC discrete components circuit from which it was built upon using transistors, diodes, resistor only but its not in the datasheet. I tried to search the web for it but it offers H-bridge with negative and...
  17. pinedo

    Help identify “a resistance.“

    Hi everybody, greetings from Portugal. I was wondering if somebody can help and is able to translate this “Martian R” ‍♂… you will get why ‍♂. R18 omh I think it is… (brown-grey-black-gold-black?) but what tolerance? (Black doesn't exist, as tolerance, and if you start to count from the other...
  18. R

    Tesla Coil Not Working. Transistor Getting Extremely Hot

    Tesla Coil Not Working. Transistor Getting Extremely Hot. See The image Below. I Did not use a switch and i did not use an led
  19. Jorne

    Component identification - resistors? [solved]

    I have some old electronic components that I got from someone who repaired TV's, radio's... I assumed these were resistors, but the measured resistance doesn't match with the color code. For the ones with the brown body (see picture), I have two of them with the color code...
  20. Tentmaker

    Help me ID: Unidentified Components: Capacitor, resistor/fuse (with fridge fiasco story)

    TLDR: ID & ideals on mangled through-hole components, images below: Story: The Torontonian's Tale of the Fridge Fiasco Out with the old, in with the new! Or, so the non-electronics hobbyist will say when an appliance malfunctions. But, me? No, siree bob! Not with a soldering iron and all the...