Questions tagged [hum]
The hum tag has no usage guidance.
29
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Locating the source of a persistent 120 Hz hum in amplifier
I'm working on rebuilding a subwoofer amplifier. The caps have been replaced, the corroded press-on tabs for transformer and speaker connections have been replaced.
Upon reassembly, the amplifier ...
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2
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Loud hum when input is connected to amp
I've just built a JLH 1969 amplifier kit that I bought online. When connected to the stereo output of my phone (isolating one channel at a time) the amp works fine one channel at a time but when I ...
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Grounding Li-ion battery pack to stop amplifier hum
I'm trying to connect a tube guitar amplifier to the Delta 1300 W battery pack by Echo Flo. The pack is not grounded, so I get a hum.
Echo Flo suggested connecting the amp to a power strip, then ...
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Can appliances or wiring hum at frequencies of 500Hz and above?
I've been hearing this strange continuous hum in my apartment for a while now. It is a small apartment and the hum is present all throughout with varying intensities, so I can't really infer from ...
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2
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Subwoofer hums when no audio source is connected [closed]
The hum stops as soon as an audio source is connected or any metal part of the subwoofer is connected to the ground of a socket.
Does anyone have any idea what the problem is?
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Connected my audio input to two music systems by splitting the input, but the one with subwoofer produces continuous 100Hz hum
I have 10 year old Creative 2.1 audio system that has fairly capable subwoofer, and combined its input with a TPA3110 2x15W stereo amplifier module (for better treble). When both systems are powered ...
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Guitar Amp Humming (interference?)
So my amp worked perfectly fine in my old setup in another part of the house, but in my new setup it buzzes when I connect a cable, and with a guitar. I thought it was a grounding issue, but it didn't ...
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why does my USB 5V power supply not need a mains ground?
Every small 5VDC power supply (wall wart style) I see has the standard 2-prong Europlug, i.e. no ground. Even those with a British 3-prong plug just use a plastic prong for ground.
Background - I am ...
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I have a single phase induction motor, with no capacitor, and can't see the shaded pole. Can you help me understand how it starts or should start?
I have a small single phase, induction motor with no capacitor. It's not missing, so this has got me thinking it should be a shaded pole. However, I don't see the shaded pole and my motor is just ...
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why does household ceiling fan electric motor hum?
I'm interested in the technical reasons behind why an inexpensive ceiling fan in a home would hum, such that when in your bedroom above your bed on low speed is annoying.
Is there a better type of ...
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Troubleshooting Hum in a Tube Guitar Amp
I have a Fender Deluxe Reverb Reissue guitar amplifier that hums whenever I turn on the reverb. It sounds like loud 60 cycle hum. The reverb effect is still applied, but is accompanied by the hum.
...
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Fender Telecaster guitar makes loud humming noise, stops when player touches strings/metal parts
I have a Fender Telecaster that hums loudly--much more so than other similar guitars. It's a standard Tele with single-coil pickups. The humming noise stops when the player touches the strings or ...
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Triac dimmer makes audible noise (hum or buzz)
I have some triac dimmer from IKEA (bought several years ago).
This dimmer makes audible noise (hum or buzz), very notable during night when it is placed on a bedside table. I failed to find the ...
- 5,334
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Active Tone Control Hum and Buzz in Potentiometer
Here is another problem with my circuits, that I cannot solve.
I am working on analog active tone control - Bass, Volume and Treble with TL081/82 chips.
The reason I put volume control on the output ...
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345
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Plus, Minus, Ground and the damn noise
I am a relatively newbie here and I am trying to build this project... so do not kick me hard and forget any stupid errors you see on the project. I appreciate any suggestions, criticism, etc., ...
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Getting rid of charge injection click and hum sound on this switch I have designed
I have designed this 4 stereo channel TRS switch.
You have 4 channel stereo input and 1 stereo channel out. You press a button and you switch which channel you want to send to the output. Once the ...
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Measurement setup for power line spectrum
I've come across a setup for measuring AC power line spectrum.
Here is the spectrum graph which shows 60Hz and harmonics in a power line voltage:
And below is the setup and wiring for this ...
- 11.8k
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Noisy amplifier for HB100 doppler module
I'm working on a doppler radar based on the HB100 module. I want to sample the signal using a microcontroller and display the speed on a LCD. But I want to have the analog front-end working properly ...
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50/60Hz Noise Harmonics
I want to wirelessly communicate over low frequencies (<1kHz), and I noticed during some tests that 60Hz noise is showing up a bit at 180Hz (3rd harmonic), and also slightly at 300Hz (5th harmonic):...
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phono preamp hum - ground loop?
I've built a simple 2 stage active/passive phono preamp. Everything in terms of amplification/frequency response/lack of distortion works fine - just as it was designed. The only thing is that hum can ...
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How good should the regulated AC/DC power supply filter be in tube headphone amp?
I am building a tube headphone amplifier. I built a AC/DC regulated power supply (220v AC to ~250v DC) but I am not sure about how good is the filter. The filter contains 120uF and 68UF capacitors, in ...
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eliminating audio hum
I'm working on a circuit that feeds a microphone into the ADC of the STM32F4 Discovery and then outputs that exact signal out of the microcontroller's DAC and then to a headphone jack.
I am able to ...
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Remove mains hum out of amplifier
I have a headphone amplifier that is afflicted by mains hum 50 Hz and upper harmonics, below is an FFT of the spectrum with nothing connected to its inputs.
In headphones you can clearly hear a buzz-...
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My printer injects hum into my USB ports [closed]
I have a Brother HL-L2305 laser printer. I love it. I also have a pair of KRK Rokit 6 G3 speakers that I run off of an MBox 3.
Every time I plug the printer into any USB port, hub or not, a loud hum ...
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How do you know if a vacuum tube is going to suffer from AC hum or not?
I know that technically there is little difference between AC or DC heating of the tube - if it gives proper voltage everything is fine... Except the hum:
I have read in various sources that some ...
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3
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879
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Mains hum without ground loop
When I hook a device to the monitor input of my digital piano, I get a very noticable 50Hz hum.
I understand that the monitor input doesn't have to be particuarly good quality, but it really is ...
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Hum Cancelling Circuit
Consider the following circuit:
I was just thinking about how connecting consumer grade unbalanced electronics together has a tendency to generate hum. For example, I have a little mixer that has an ...
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How to filter hum from transformer for audio rectifier
i´ve just build a prototype speaker from a TDA7293 (http://www.ebay.de/itm/TDA7293-85W-100W-Mono-Audio-AMP-Amplifier-Board-AC12-50V-Update-vision-TDA7294-/201478109342), the circuit is quite ...
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How to remove mains hum from a BNC cable?
BNC cables are used as inputs to a data-acquisition hardware.
If long BNC cables are picking up the 50/60Hz mains hum through the air like antenna, how can I filter this? Would connecting the BNC ...
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