The sampling tag has no wiki summary.
0
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1answer
70 views
Interference beetween ADC samples with XBee and photoresistor
I'm using an XBee serie 2 module for sampling the values of three sensors, a photoresistor (LDR) a moisture sensor and a temperature sensor (LM35). When there is no brightness the photoresistor has ...
3
votes
1answer
122 views
8~16 PDM digital microphone + what processing? = beamformer!
I am researching on a project about sound source beam-forming.
I'd like to build: 8~16 digital microphones into one 2D(circle)/3D(sphere) PCB to form an array with an equal separation of each mic 3cm ...
0
votes
1answer
117 views
what is the difference between sample method and sample and hold method
I want to know what is the difference between sample method and sample and hold method ,and why are these two methods important to study analog to digital conversion and its reconstruction back to ...
2
votes
2answers
727 views
How can I find a specific frequency after doing FFT?
I have some samples from an SDR that I run through FFT and I want to detect the presence of a specific signal, exactly 148.369MHz.
The maximum sample rate of the device is 2Mhz, this is just ...
2
votes
1answer
399 views
PIC analog to digital converter to measure more than one battery voltage (with different grounds)
I'm trying to build a circuit that can scale down several lipo batteries (5 cell) up to 22V max to be safe to either 3.3V or 5V for measuring with a PIC microcontroller using the analog to digital ...
1
vote
2answers
201 views
Periodic graph in frequency domain
Why is that the frequency domain has the same shape all through out? Look at figure b
3
votes
2answers
151 views
How to measure, with timestamps, changes in the received luminance?
I'm working on a project that is in need of some testings to validate it. I need to make some readings of luminance from a light source and store this reading with a timestamp (milliseconds ...
2
votes
1answer
418 views
Wifi limitations
What are the limitations of using wifi where you have say 30+ clients/devices pushing compressed audio (flac)?
bitrates: ~384 to 768 kb/s (44100 x 16 x 1 to 48000 x 16 x 1) * ( 0.5 to 1.0 )
(sampling ...
1
vote
4answers
463 views
Measuring low current at very high speed
I have a circuit with a very-low-power Jennic JN5148 module with microcontroller and 2.4 GHz radio, and some low-power sensors.
I have to measure the supply current of all these components, in an ...
23
votes
7answers
2k views
Why are digital oscilloscopes still so expensive?
I'm a beginner in hobby electronics and I am wondering
why digital oscilloscopes are still so expensive?
In times of cheap GHz CPUs, USB 3, ADSL modems, DVB-S receivers, blu-ray players which all of ...
8
votes
3answers
1k views
Why is the Nyquist data rate lower than the Shannon data rate?
In the book Computer Networks, the author talks about the maximum data rate of a channel. He presents the Nyquist formula :
C = 2H log\$_2\$ V (bits/sec)
And gives an example for a telephone line :
...
1
vote
2answers
851 views
Highest ADC input signal frequency for atmega8?
I am trying to make a simple project which involves acquiring some data from the adc of atmega8 chip and then sending that data to UART. But I cannot figure out what would be the maximum limit of the ...
14
votes
5answers
2k views
How do digital oscilloscopes achieve such high sample rates?
From the perspective of data capture, how is this achieved? If I wanted to implement a home-made digital device to capture high frequency analogue signals, what are my options? So far, I've only come ...
2
votes
5answers
1k views
How to sample audio at Nyquist frequency with MSP430F5438?
I want to:
Input an analog audio track
Using the microcontroller ADC, convert it to a digital output
Then have the microcontollers/boards timer sample the data at selected intervals
Resample the ...
2
votes
1answer
176 views
What should I be using to amplify a heat flux and load cell signal?
For my senior design project, we have various sensors (Thermocouples, Heat flux sensors, load cell) plugged into our DAQ. We are using LabView and some National Instruments devices (ugh) and ...
4
votes
3answers
648 views
Increasing ADC resolution by supersampling on a successive approximation ADC
Is it possible to increase the resolution of an ADC by supersampling on a PIC24F ADC, which has 10 bits of resolution and is implemented using a successive approximation engine? Speed is not critical ...
3
votes
2answers
592 views
Equivalent time sampling on microcontrolers
I must admit, I don't know too much about analog electronics but I am keen to know if it possible to construct an equivalent time sampler (ETS) using the A/D's on a micro.
I hope this question isn't ...
6
votes
2answers
727 views
What's the difference (electrically) between AC- and DC-coupled sampling circuits?
I've noticed that in analog signal acquisition hardware you see two paradigms: AC-coupled and DC-coupled. Typically AC-coupled hardware is less expensive, and basically has a 20 Hz high-pass filter ...
9
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8answers
10k views
Maximum sample rate of Arduino Duemilanove?
G'day all!
I have an Arduino Duemilanove hanging around spare at the moment and thought I might try a few audio interfacing projects. I'm just wondering what sort of sampling frequency I can achieve ...
