1. zeke105

    Wiring connections for car amplifier with sub for home use.

    Im new to these kinds of stuff, very noob question here but I found an old car amplifier with a sub on it (attached photo). I’ve watched YT vids on how to actually make it work. Im just wondering if in the “bridged” speaker out i can just put a female 3.5 mm to bare wires. since i only have...
  2. R

    Designing a 0.18-µm CMOS Multi-Stage MOSFET Amplifier (150 V/V Gain, 1-5 GHz) Without External Resistors/Capacitors

    I'm working on a project to design a full-transistor-based (MOSFET) multi-stage amplifier using 0.18-µm CMOS technology. The requirements for the amplifier are as follows: Voltage gain of at least 150 V/V Input resistance less than 1 kilo ohm Upper 3-dB frequency (fH) between 1 GHz and 5 GHz...
  3. vouzmevoyez

    Unable to get lower duty cycle for monostable w/ astable input via opamps

    Hi, I have to keep my frequency ~800Hz which means T = 1.25ms. Using a variable resistor, I have to get a duty cycle of 65% (which I achieved @ Rpot = 23.5k ohms) and 15% when the potentiometer is at 0. However when I try to trial and error simulation values, my output waveform doubles per...
  4. G

    Zener Diodes in series as Voltage Regulators

    I’m attempting to confirm my approach to this project circuit. I’m wondering if the 2 halves of the circuit (as shown) would work well to drive the Load, or even work together well at all. (It’s been a while since I was designing circuits (30+ years) and I’m a bit rusty.) I’ve done a...
  5. jkelly662

    Amplifier Crowbar Circuit Help

    Hi, I've reverse engineered the crowbar circuit on a large amplifier I'm working on. I understand the basics of how a crowbar is supposed to work, but this particular design is difficult for me to grasp. The input voltage is +/-250 VDC. The K1 relay appears to disable the crowbar when the relay...
  6. Rahulk70

    Recapping and FM tuner station issue on Technics SA-5360 Stereo FM/AM tuner amplifier

    Hello everyone, I had recently purchased a Technics SA-5360 Stereo amp tuner from eBay. This was after a long break since 2019 I took from my vintage electronics hobby. I used to mainly collect and restore tube based tuners and amps, but recently it has become quite expensive I noticed...
  7. conandrum

    Mute BMW head unit

    Hi all, this is my first post here: Mute button: My BMW head unit has a mute/volume button. The encoder, when pushed-in mutes the head unit. Today, I accessed the encoder and soldered 2 wires on the 2 pins which join when the encoder is pushed-in. See photos/video. Triggering: I have a...
  8. boromyr

    Problem with guitar amplifier: distortions in the higher notes.

    Hello, I am building an amplifier for an electric guitar, and I am encountering an annoying issue when playing the higher frets of all 6 strings of the guitar (Stratocaster) with more force: when playing a string after fret ~19 with greater intensity, the sound distorts, as if it were an...
  9. Q

    Would You Be Interested in an Affordable DIY Lock-In Amplifier?

    During my PhD, I spent countless hours conducting optical experiments, where lock-in amplifiers became an integral part of my research. Their precision and effectiveness were unmatched, but so was their cost. Recently, while doing a personal optics project, I found myself in need of a lock-in...
  10. M

    I made an oscilator, but i need a amplifier to change the amplitude

    I made this oscillator and the output voltage is 1V, and I need another amplifier to go to 5V and some mv ideally to 10mV, but that is harder. I made this but it doesn't work very well and I don't understand why. I can't work with OpAmps, with only transistors. I put a common emitter with a...
  11. J

    Class D Amp - Where in the circuit is the PWM occurring?

    Hello, I have a Class D amplified speaker I am trying to fix (circuit attached). The fault at the moment is that when the speaker is powered on, and with no input signal, one of the speaker channels half-bridge configured FET's begin to immediately overheat. Hot enough that it turns the solder...
  12. BeholdenLemon71

    Is it possible to make an amplifier with the tda8588bj/r1 ?

    I have an old bronken sony cdx-gt207x and I wanna know if it´s possible to make an amplifier with his tda.
  13. violapwr

    Summing Amplifier Channel Isolation Problem

    I'm designing a quad-preamp circuit (for an experimental musical instrument). Each pre-amp channel is read by the analog input of a microcontroller before being summed together. The issue is that there is a ton of crosstalk being reported by the microcontroller between the four channels. I'm...
  14. U

    RF Amplification problem

    Hello, I work on an exercise I made up for myself and I need some help. I want to build a small RF receiver with a central frequency of 50MHz. I made a model of the antenna. I put a band pass filter after it. Both are centered around 50MHz. I want to amplify the received sine with a 7V voltage...
  15. JohnSnow16041992

    100K preset with AD620 instrumentation amplifier good idea or bad?

    So I am planning to use an AD620 instrumentation amplifier in my circuit. The gain formula is G = 1+(49.4KOhm/Rg), Rg being the deciding resistance value. By that logic if a 100K preset or Pot is set to zero, Gain attempted is (∞ + 1), which besides being impossible is also way above the 10000...
  16. kapcina

    Amplifier with 500 voltage gain

    I want you make a amplifier with 500 voltage gain and use a amplifier with common emitter, but I can't get a gain over the 100 with any value of resistors. Vdd is 12 V and b is 100
  17. blink13

    Seeking Advice for Three Stage Amplifier Project: Improvements and Real-Life Feasibility

    Hello, I am a student tasked to build a working amplifier, I do not know much of what I am doing. I've got a three-stage configuration that consists of a single ended differential input stage, a common-emitter VAS stage, and a Sziklai pair output stage. It's supposed to be a 15W amplifier to a...
  18. C

    Need help with FM Radio Transmitter / Amplifier

    So I purchased this : (HanRongDa HDR-831) HanRongDa HDR-831 It's working great but the practical range is about 15 meters. I'm looking to upgrade this. The thing is, I know very little about radio frequencies and antennas. Can something like this work ? Ebay Amplifier The device I purchased...
  19. henry4700

    Clipping Class AB Amplifier output

    Is there any problem of my circuit? How can I fix the clipping?
  20. S

    Need help with identifying the topology of this Amplifier Circuit

    What is the purpose of this circuit?
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