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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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
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...
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...
Hi,
I'd like to build one of these:
https://phys.org/news/2006-04-lunar-buster.html
Basically it's a sort of static electricity linear motor that pushes dust around. I understand general principles of electronics and have built a few circuits from kits, but that's about it.
I figure this...