Questions tagged [acoustic-noise]
The acoustic-noise tag has no usage guidance.
23
questions
1
vote
0answers
73 views
What to check for hissing noise in a LCD monitor and how to reduce it?
I have a Dell LCD (LED backlight) without speakers which produces an audible "hiss" when connected the HDMI input. DisplayPort much less.
I have recorded the following spectra:
monitor off (this is ...
2
votes
5answers
450 views
MC34063 based converter accoustic noise
I am trying to make nixie clock and I use MC34063 for buck/boost converters. The nixie tubes require 180 V to operate and the microcontroller and LEDs need 5 V. I use external 20 V power supply as a ...
4
votes
3answers
142 views
How is that “howling” sound produced in induction motors?
Note: No, there are no inverters involved in this question here.
I've perceived that most, if not all induction motors make a "howling" sound in their coils that is different from the constant 60 Hz ...
0
votes
1answer
52 views
Bad background noise in audio capture [closed]
I have a microphone attached to a Realtek ALC5640. The circuitry is as below:
L9 is Murata BLM15PD121SN1D
The noise capture is here.
How could I improve the situation and reduce this noise, if ...
0
votes
2answers
34 views
Noise testing method
I have Electronic board with power supply , control board etc. I wanted to conduct noise test . Is there any standard procedure available.
I wanted to check if i induce the noise into power line or ...
0
votes
1answer
378 views
using a vibration / noise sensor as edge finder in a CNC machine
I have a desktop CNC machine which has just the basic functionalities like controlling the speeds and position with a somewhat reasonable accuracy / precision. I also have an edge finder which I can ...
1
vote
2answers
75 views
Circuit Choices for AmpIifier Input
i have breadboarded a TDA2050 amplifier, using this schematic
i get good sound intensity with a half acceptable quality. the down side is the constant noise and humming. i have found a possible ...
0
votes
1answer
420 views
How to remove noise from microphone input?
The Issue
I've made a project centred around the XS3868 module which is based on OVC3860. The circuit works fine and I was able to get the microphone to work except for just one thing, the mic input ...
0
votes
1answer
91 views
Clarity on dB SPL calculation
Based on this post, let me assume that I have a input source of 94 dB SPL / 1 Pa that a microphone is picking sounds from.
The microphone has a sensitivity of -46dBV/Pa , this gives 0.005012 V RMS/ ...
0
votes
1answer
42 views
Detection of Acoustic signals
There is a scenario: There is a certain box which emits acoustic signals at 30kHz and you are trying to detect these signals using some sort of detector.
I was wondering, would it be more efficient ...
0
votes
1answer
119 views
I have an outlet adapter that is clicking at 260bpm. What is happening? [closed]
I plugged this adapter, GE Grounded Adapter-Spaced Six-Outlet Tap, into my outlet the other day. I noticed a clicking noise in my apartment, and it's coming from the adaptor. I used an online app to ...
2
votes
2answers
215 views
Is it possible to generate different PWM Signals for same duty cycles(e.g. 50%)?
Let us expect we have a duty cycle of 50%. Is it possible to reach that duty cycle with different PWM Signals (waveform)? With different I mean variants in the number and lengths of the "active time". ...
1
vote
1answer
143 views
High pitch sound coming from Low-Dropout Linear Regulator (1117 3.3V) setup
I am using the below schematic to drop voltage from 5V to 3.3V (1117 3.3V - http://www.farnell.com/datasheets/2100276.pdf?_ga=2.141255921.210515873.1532314816-790306462.1508240417) for a Wifi Micro-...
-2
votes
1answer
109 views
Switch a line level audio signal - which chip is best WRT noise, low loss? [closed]
I am relatively unexperienced with audio circuits, and need to switch a standard line level signal, AC, about 6Vpp. I have the chips listed below, and would very much appreciate some pointers as to ...
-1
votes
3answers
389 views
How to control the brightness of an AC light bulb with the instant level of noise nearby
The device I want to make is simple to describe: a big red lightbulb, connected to the AC 110 / 220 V, stays dark when it's quiet in the room, starts lighting up somewhat if there's a moderate level ...
3
votes
3answers
159 views
What device/component from the early 1940's can listen to only a specific narrow range of acoustic frequencies?
This website briefly describes the development of the first active acoustic homing torpedo of the US Navy:
Investigation of the use of echo-ranging equipment or an "active" homing torpedo system ...
8
votes
2answers
171 views
Is the maximum audible noise from power supplies regulated in Europe?
Power supplies make sometimes a lot noise in the range of kHz. Is there a regulation for the maximum allowed noise emission for consumer electronics on the European market?
Is there a regulation ...
1
vote
0answers
290 views
Audible Ticking in Audio Opamp Circuit
I'm experimenting yet again with the following audio mixing circuit:
On the scope with signal gen as source, everything looks great. When hooked up to the input of a mixer with a laptop as the source,...
0
votes
1answer
62 views
Troubleshooting Noise/Quirks in Audio Circuit
I am working on a project that takes in a single line-level audio channel and outputs 2 balanced/unbalanced +/- outputs from that channel. I have read a number of the excellent published articles ...
0
votes
1answer
143 views
What can cause a very low frequency sound from a laptop? [duplicate]
I have a Clevo M57RU laptop here. Whenever it goes to stand-by, sleep or is shut down I hear a VLF sound (presumably close to the ~20 kHz maximum of the human ear) that's even better to hear if the ...
1
vote
1answer
793 views
Buzzing power supply
I have a power supply that buzzes when nothing is connected and is silent when there is a power drain. What could it be?
It's a PC power supply that I used to power an LCD through its 12 V line.
3
votes
3answers
386 views
Why do wall plug power supplies use audible switching frequencies?
Every plug-in power supply ("wall wart") I have ever used starts off silent, but eventually starts to emit high frequency switching noise. It usually happens only when the charger is on, but not ...
5
votes
1answer
3k views
Audible noise in DC-DC buck converter
In my design, I have a +3.3 V SMPS that provides power to digital circuits (microcontroller, EEPROM, etc.). The microcontroller allows applying a 100 Hz PWM signal with variable duty cycle and with an ...
