Normally related to EMI (see [tag:emc])

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0
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2answers
49 views

Grounding dc project to clean RF noise

I'm doing a home automation arduino / RFID project and using a 12v DC switch mode power supply to power it. This supply will be plugged in to a wall outlet. The project however will have some ...
2
votes
2answers
65 views

How to avoid interferences (antenna effect) in long traces in PCB?

I am working on a PCB layout in which I have a 40cm long traces (bus of 4 traces). This traces will support between 50mA to 100mA and 5V. I want to minimize possible antenna effects that may occur due ...
1
vote
1answer
51 views

Weird noise waveform on signal line

I'm doing some electrode recordings and a large noise waveform keeps appearing on the oscilloscope (see pic attached). Interestingly the recording set-up functions just fine with a clearly ...
0
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2answers
53 views

Minimum separation between antennas in receiving

It's known that there has to be a separation between antennas of same frequency to minimize interference. But this is really necessary when antennas are mostly in reception mode?
3
votes
4answers
99 views

Humbucker-style microphone interference cancelling

For a recent experiment, I decided that it would be a good idea to try to add some electric guitar distortion effects to my otherwise Classical flute playing. In order to do this, I attached a small ...
1
vote
2answers
46 views

WWVB antenna interferance from AC/DC converter supply

I'm working on a design that uses a WWVB antenna receiver.... The WWVB antenna is a small (~ 1/4" x 4" rod). Size is not a constraint so I could make it much bigger if a I half to. The design is ...
0
votes
5answers
105 views

Will the data throughput decrease if the transmitter and receiver are in motion?

What I'm thinking of is a 2 way communication (voice communication) between two systems which are in motion. (like 100 km/h difference) Will the data transmission and reception be disturbed, by how ...
1
vote
2answers
64 views

12V vs 5V servo

I am looking to actuate a throttle on an internal combustion engine. I am using a 5V servo driven by an Arduino Mega2560 at the moment. The throttle is very close to the engines alternator and there ...
2
votes
1answer
103 views

electronic interference generated by blood? [closed]

Hi so i made a little electrical signal detector that can detect electrical interference/noise(for example putting it near a light or plug makes it squeal). I was messing around with it and noticed it ...
15
votes
1answer
171 views

Unusual interference [closed]

I'm experiencing an effect somewhat like GSM frame-rate audio breakthrough in my auditory systems - completely different frequencies but equally wideband. I've noticed it occasionally in the past - ...
3
votes
4answers
404 views

Dealing with signal noise over 50 foot communication link

Situation: Connecting a motor controller to an MCU. Motor controller is about 50 feet away from MCU. Connected via a single conduit (buried), containing the following cables: (There is no other ...
2
votes
1answer
63 views

Oscillating Amplifier

I am attempting to build the following amplifier The amps used are MAR-8A+'s from minicircuits C1, C2, C3, L1 - while these are available on the board they have not been placed The filters are epcos ...
1
vote
1answer
73 views

Crystal grounds and minimal trace distance to leads

Some questions have already been asked about crystals but there's a few competing designs and I have a few "obsessive" type questions on layout. Here's a almost completed layout with a PIC16F ...
3
votes
1answer
117 views

How can I use multiple Arduino-read photo resistors without interference between them? [closed]

I'm working on a prototype that utilizes a combination of photo resistors and LEDs to simulate a "tripwire" to detect when a coin falls through a clear tube. When using one tube, one photo resistor, ...
2
votes
2answers
37 views

Help with RF interference

I run an animated Christmas light show on the house, and that interferes with my garage door opener whenever the lighting electronics are on. The lights themselves don't have to be on, the problem ...
1
vote
1answer
62 views

Ballanced BNC cables?

I'm working in an experiment with high voltages and unfortunately a high voltage AC source is affecting the signal in my BNC coaxial cable (which is going into an oscilloscope or some other measuring ...
1
vote
1answer
48 views

Do short circuits between transformer windings cause noticeable change in EMF?

I am looking into developing a sensor system to be placed within a transformer. This sensor system in theory, should be able to detect any unprecedented change in EMF within the transformer enclosure. ...
1
vote
1answer
180 views

GPS antenna ground plane design considerations and limitations

I have a PCB design which incorporates a GPS unit. I'm looking at refining the PCB, and I'm looking to do away with the long cable length, occupation of space within my enclosure, current ...
5
votes
1answer
258 views

GPS consideration for PCB with GSM (interference, setup etc)

I am working on a project which has a GSM and GPS on the same PCB (fairly near each other in an enclosure). Since I am not familiar with GPS I was wondering if any of you could give me some tips on ...
1
vote
1answer
71 views

Credit Card Swipe Interference

I am asking a question as a part of library maintenance for electrical equipment. We have installed a POS machine with credit card swipe on the same outlet as a laser scanner (used to check in ...
0
votes
1answer
76 views

Mobile WIFI: how close can mobile devices be placed and still have a functional WIFI connection?

I wish to run a large array (50+) of hacked Android phones as a computing cluster. They will need to be networked so I plan to use their built-in WIFI radios to talk over a single WIFI network. (I ...
2
votes
2answers
454 views

Using PC audio to listen to electrical noise on power line?

I have done a bit of research on digital filtering and I was wondering if it would be possible to use the audio hardware of my computer tu listen to the electrical noise on my powerline ? If it is ...
0
votes
2answers
406 views

2.4GHz Wi-Fi interference between devices in close proximity, even though they're using completely non-overlapping channels?

Is there any known electromagnetic / interference / [no idea] effect which can cause IEEE 802.11 (Wi-Fi) 2.4GHz devices located in very close proximity (one on top of the other) to severly interfere ...
1
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0answers
96 views

Will the following circuit cause EMI-problems?

I'm trying to get a feel for which circuits will have EMI-problems and which won't. To make things a bit more concrete, I've designed a super-simple LED-blinking circuit using the PIC16F1788 ...
0
votes
3answers
104 views

Via fences or pickets important parameters for design

What is more important for EMI shielding effectiveness with respect to guard traces and via fences, the width of the copper trace that circles around the area or the distance between the vias to ...
1
vote
3answers
76 views

Electrical noise sources in farms

I am designing the data logger of a solar-powered automatic weather station that will be installed in farms. It's used to gather data from environmental sensors (wired) and send it to a host using the ...
1
vote
1answer
148 views

Wi-Fi transmitter/receiver in close proximity: Override interference?

I'd like to control a camera via Wi-Fi (zoom, trigger shutter, etc.), and possibly also capture a live video stream. This will be at an event with a huge number of Wi-Fi devices, and connectivity is ...
0
votes
3answers
174 views

How does EMI affect a circuit? [closed]

I was designing pcbs and my head engineer told me that if input supply is large then there should be a separate layer for ground and positive supply as this will reduce EMI effects on the nearby ...
1
vote
1answer
89 views

GSM module noise

I'm developing an embedded system that uses telit gl865 modem to connect to a server using gprs. I've noticed that the module makes a strange noise when connected. It's the same noise I used to hear ...
0
votes
1answer
99 views

Usefulness of line EMI Filter on bench power supply

I have read this pdf file about EMI filters. I'm about to construct a variable bench power supply of 12V/5A. Will there be any usefulness to add an EMI filter to the primary windings of the ...
1
vote
1answer
121 views

Two 2.4GHz radio modules (XBee+Bluetooth) on same PCB. How to minimize interference?

I'm designing a PCB with XBee radio module and a bluetooth module (RFDuino SMD with XBee 2mW Radio). Since both of these modules are using 2.4GHz, are there any special consideration about how to ...
0
votes
1answer
114 views

Will coiling a mains power electrical cord cause interference?

I am a maker working on a lamp design in which a decorative power cord is wound through the structure, creating a coil down the lamp's main structure. The coils are about 3cm apart and the same in ...
0
votes
0answers
52 views

Parallel connection between two circuits 15cm apart

I need to connect two PCB that must be 15cm away from each other. I considered an IDC connector with ribbon cable like this http://www.zagipalma.es/images/USBASP/USBASP%2010%20a%206%20Pines%2011.jpg ...
0
votes
1answer
142 views

Multiple hall effect sensors in proximity

I'm interested in using a linear Hall effect sensor to measure displacement varying by about 1.5 inches. The idea is I have a piston with a magnet at the end and a Hall sensor at the end of the cavity ...
2
votes
2answers
922 views

How to shield for electromagnetic interference (DIY level)?

I am building an optical rotation encoder for my "autonomous robot" (a LED pointing to a photodiode that gets interrupted as the axis rotates). My issue is that at the voltage that I am using the ...
0
votes
1answer
181 views

5V TTL signals over 4m or so?

Adding input and output capacitors either side of my 5V DC-DC converter doesn't seem to help much, and I'm wondering if some kind of signal interference might be my problem. I'm running signal from a ...
0
votes
2answers
58 views

What can be used for impromptu EMF shielding?

I have a robot with a lot of servos in close proximity and a high-current DC motor powering an airsoft gun. The motor is causing electromagnetic interference with the servos, and we need to shield it ...
0
votes
2answers
124 views

Does gauge size of a signal wire has an effect to its susseptability to electromagnetic interference?

Let's say you have the option to use a lower gauge wire size (i.e. thicker wire) for a signal wire that happens to be run along power wires. Will it pick up more electromagnetic interference than ...
2
votes
2answers
163 views

Sensible standard wiring type for long-range I2C

I'm planning on interfacing with some sensor devices via I2C over a long bus, with devices chained every 2m or so, up to 16m in total. I've seen other questions here referring to this from the "which ...
1
vote
0answers
129 views

HF RFID 13.56MHz Interference from WiFi/BLE 2.45GHz?

If a Wifi/BLE antenna were placed within a multicoil loop antenna for 13.56MHz HF RFID, would there be significant crosstalk/interference?
1
vote
1answer
59 views

3 axis magnetometer issue in one axis

I have several 3-axis magnetometers mounted on breadboards, and they all read correctly in the x and z directions. The Y direction is very strange; when turned to read ...
-2
votes
1answer
189 views

Strange TV Blue Screen issue on switching on any home appliances [closed]

i have recently purchased Android Tv Box CS928 from Chinese site http://www.aliexpress.com/item/CS928-Android-4-4-kitkat-Rk3288-A17-quad-core-2GB-16GB-2-4-5-0Ghz-100M/1939723909.html The Android TV ...
0
votes
1answer
73 views

Can a rotary incremental encoder, count more steps due to interferences

I have an incremental encoder having differential signals A-NotA, B-NotB I-NotI, that apparently randomly seems to count more impulses. It is possible to have more impulses due to electrical ...
8
votes
4answers
7k views

Wireless Home Automation 2.4GHz versus 433MHz [closed]

Project specifications To make some things clear first(wow that sounds so arrogant): This is an Arduino project This is supposed to be internationally applicable I have experience with 433 MHz ...
-2
votes
1answer
379 views

Bluetooth Interference with High Pitched Tone

i'm building a portable stereo system and am having some unwanted noise from the bluetooth receiver. the noise is typically a high pitched tone. please see the attachment for my chicken scratch ...
0
votes
2answers
124 views

Suppressing interference in a pressure sensor circuit

I just looked over a circuit designed by my predecessor, which is used to interface with a pressure sensor. It works, but I have some doubts about the way the input filtering is done. The simplified ...
2
votes
1answer
175 views

pH sensor project: trouble with RF interference

I built this pH sensor project on a breadboard and I'm having a big problem. The output on the voltmeter is completely erratic, and I'm pretty sure it's due to RF interference. When I connect the ...
2
votes
1answer
51 views

Atmel and coil close on a board - is interference an issue?

I'm going to build a circuit which uses AVR uC (probably ATmega8 or some ATtiny) and a coil with iron powder ring core. The coil has 330uH and will be working under current of approx. 6A. I'd like to ...
1
vote
0answers
213 views

Isolation between GSM and GPS antenna

We are doing a prototype for a gps based tracker. We got a problem in placing the GSM and GPS antenna. Both the GSM and GPS antenna are omni-directional antennas. In forums and application notes, the ...
2
votes
1answer
276 views

Microcontroller freezes (or doesn't) when plugged into different outlets in my home

I have an ARM development board (Marvell ARMADA XP CPU) and depending on which plug outlet I plug the system into, the system will freeze up after a few minutes or not. I found that plug outlets in ...