1. E

    Amplifier Noise Reduction

    How can I reduce Noise in this circuit?
  2. A

    AD630 Lock-in Module Resistor Experiment Troubleshooting

    Hello everyone, I'm trying to use this board as an analog lock-in amplifier; however, I'm running into some difficulties due to a lack of any documentation on the use of this device in lock-in experiments, save for PhysicsOpenLab blog post that performs the experiment I'm trying to replicate...
  3. C

    Summing Amplifier - Revisited

    Hello Everyone again, I have a continuation from my previous problem from my adjustments and testing that I was hoping to get help on. I am doing a multi channel mixer that pipes audio signals to different channels to go to different speakers. My previous post have pointed me to fixing the...
  4. Jisan0077

    Panasonic su ch 7 stuck on standby

    My amplifier panasonic su ch 7 stuck on standby. Why this problem and how can i solved it
  5. L

    Balanced Audio Preamp Circuit

    I tried to make a preamp circuit but I'm not getting any output at all. The simulation on LTSpice seems to work well. The Op Amp I'm using is LMV821 datasheet I'm using a balanced dynamic microphone Zener Diode is 5V1. I don't mind if its noisy as long as I get a some sort of amplification from...
  6. Alex_Khan

    Designing Differential amplifier with differential output

    Hello! I have done calculations for designing a differential amplifier (DA) with differential output. I simulate (using cadence ) the DA with the calculated values and perform the DC analysis of the circuit to inquire all the transistors are operating in saturation. However, I did not get all...
  7. cikalekli

    Input and Output Impedance of the Common Emitter Amplifier

    Hi, I just have solved one of the bjt common emitter question below. However, I'm curious that how can I additionally find those things below: 1) Input and Output Impedance 2) AC Gain Here is the example and my hand draw solution. However, the question only asked to find Vout/Vin... Also, my...
  8. Ivan Badal

    compute gclosed as a function ??

    I have this inverter and do not know how to compute gain gclosed as a function of R1,R2,R3,R4,R5 and R6?? V out = closed * Vin. Circuit is in attach file!!
  9. Pashgen

    How to find a mistake. Sound amplifier circuit board. Need help with troubleshooting

    Hi, I bought DIY amplifier board. And now I am trying to find what I did wrong. It can work for about 2 seconds and then sound dissappear. But power stays on, and LED is glowing I connected 24 volt toroid to start the board. In description it says that circuit is designed for 12 to 36 AC...
  10. A

    Type 807 Tube RF amplifier with transistor a pre amp

    Hi all, I have a 807 vacuum tube and I want to make a CW RF amplifier with it. I am thinking of using transistors in pre amplifier and 807 as final power amp. I have only one tube so I cannot make push pull amp. First of all I need to know if it will be possible to make such RF amplifier. If...
  11. A

    Peavey Centurion Mark III head with high DC voltage output

    Hello, I have a 1980 Peavey Centurion Mark III head that was buried in my garage unused for 15 years. I knew it had problems (it's not mine, i got it from a friend who was throwing it) so before doing something i checked all the components and everything looked great. Once done I plugged it to...
  12. Shotkx

    Help with KEPCO power supply used as AC amplifier

    Hello everyone! I was wondering, how can I understand what is the frequency input range that the KEPCO BOP 72-6m can amplify, when used in current mode, with a sinusoidal waveform as control input ? Should I referent to the BANDWIDTH (d-c to f-3dB) in the Datasheet? or to the LARGE SIGNAL...
  13. T

    Audio Amplifier Without Volume regulator

    Hello, I need Some help, if its possible Problem Description: I've Got Ceiling Speakers Pair (150 Watt each, Max). It has Some Amplifier in box, with only AUX (3.5 mm) audio port and Bluetooth option. It has no volume regulator or anything else. (model No. AMP-BTX 01) I've Mounted it in Ceiling...
  14. genekuli

    I need some help putting together a wideband, radio frequency amplifier and a UWB antenna.

    Hello, I would really appreciate it if there was somebody who could just help me by telling me how to make this. It needs to be only the very bare bone components without any filters. I just need to be told what I need to buy and how to put it together. Ultra wideband, frequency range...
  15. R

    Advice on powering my diy guitar amplifier

    Hello, my name is matt. I have a few questions about supplying power to my audio amplifier projects. I have made 4 Bluetooth speakers and 1 small guitar amplifier so far. All of the Bluetooth speakers have been powered by a 5v battery power supply. Simple Bluetooth amplifier boards and a...
  16. genekuli

    If I hook up a HF ultra-wideband (UWB) amplifier with a transmitting UWB antenna (out) and a receiving UWB antenna (in)

    If I hook up a HF ultra-wideband (UWB) amplifier with a transmitting UWB antenna (out) and a receiving UWB antenna (in) and have the antennas very close (few inches) to each other inside a metal box (~40cm) so as to produce a feedback loop, then due to the noise and harmonics of the over-driven...
  17. xenon_eleven

    Active Butterworth Bandpass Filter unexpected peak

    I am currently trying to design a bandpass filter in a simulator for a university assignment to the following criteria: Frequencies below 1KHz and above 250KHz should be attenuated. Note that you will need to calculate the cut off frequencies given the pass band (1KHz to 250KHz) should not be...
  18. GastonJam

    Transistor as an amplifier

    I'm currently working on this circuit and I run upon this question which I'm not sure I understood it correctly : For starters I have these values below - UCE=5V R1=6.1kΩ R2=1.35kΩ RE=1kΩ R3=1.5kΩ V1=15V IC=2mA UBE=0.4V B=180 Given formula rBE≈40mV / IB First I calculated CE with the use...
  19. CobraL0rd

    Old Amplifier reeks a burned smell and smokes after being turned on

    My mom has an old ~40 year old audio amplifier LUXMAN L-210, that hasn't been turned on for about a decade. I found some time the other day and turned it on to see whether it's working and how it's performing. So it did turn on and seemed to work (I have radio tuner, cassette player and disk...
  20. P

    Electret microphone to speaker circuit

    Below is the circuit I created. I'm trying to to get the electret microphone to amplify through the PAM8403 amplifier into the 4Ohm 3Watt speaker. The PAM8403 has an operating value of 2.5V-5V, claims to work with speakers from 4-8Ohms, and speaker power from 2W-8W. Did I get connect something...