How many times something happens per second, measured in Hz (Hertz).
0
votes
1answer
44 views
How frequency generator in telephone works
I was doing some research, on how telephone works, and I found that when user, click numbers they are converted to frequency and passed to wire. I want to know how the frequency generator work, what ...
0
votes
1answer
28 views
What frequency bandwidth should an accelerometer operate for measuring punching and kicking movements?
I'm trying to choose the bypass capacitors for a schematic circuit that measures the acceleration (in g) for punching, kicking, throwing, etc. But I don't know what to place on the x, y, z output of ...
0
votes
0answers
25 views
Low Frequency signal detector with MOSFETs
Does anyone have any ideas on creating a very basic signal detector (low frequency is fine) with MOSFETs? trying to design a small profile detector.
My idea was to use a basic field strength meter, ...
1
vote
2answers
32 views
Best circuit to get an array of signals with the same frequency and edge-synchronizable to a reference but individually controllable duty-cycles?
I am looking to build a circuit to control five different FET drivers individually. The input signal would be a single shot from a function generator, which should produce five output signals, with ...
1
vote
2answers
71 views
Variation of voltage gain with frequency
For a transistor amplifier, the voltage gain
(a) remains constant for all frequencies.
(b) is high at high and low frequencies and constant in the middle
frequency range.
(c) is ...
3
votes
2answers
165 views
Micro-controller failure problem as the temperature raises
I'm using at91sam3s8b(cortex-M3) for my project.The hardware board connects to PC using USB port. The firmware contains some cryptographic algorithms (it includes shifts, Xors, memory substitution ...
-2
votes
1answer
50 views
Amplifiying a 40kHz square signal to a higher frequency [closed]
So I designed a circuit with these two main parts:
1. The timer, powered by 12V DC consists of a 555 timer circuit enhanced with Op-Amp regulator circuit. This part is connected to irg4ph40upbf IGBT.
...
0
votes
1answer
36 views
DDRx Memory: Memory Clock vs I/O Bus Clock?
When referring to DDR/DDR2/DDR3/DDR4 memories, I am not able to understand the difference between memory clock and I/O clock.
As per: https://en.wikipedia.org/wiki/Double_data_rate
DDR-200 - Memory ...
0
votes
0answers
25 views
calculating delay cycles for hcs12
I try to calculate number of instruction cycles and delay cycles for HCS12. I have some information about HCS12
The HCS12 uses the bus clock (E clock) as a timing
reference.
The frequency of the E ...
0
votes
3answers
100 views
Operation of LC circuit in Frequency Modulation with simulation and linking it to the basic principle of frequency modulation [duplicate]
Can somebody help how message signal (words spoken near microphone) is modulated using LC circuit and how lc circuit oscillates at particular frequency by applying dc voltage. In the below circuit ...
1
vote
4answers
149 views
How to control the driving frequency when working with high power ultrasonic transducers
I would like to know the simplest solution to dynamically tune the driving frequency of an ultrasonic transducer to its resonance frequency.
My amplifier has a power meter that I can read an optimize ...
1
vote
0answers
27 views
Relation between frequency and inductor current
I have a question regarding frequency and inductance. What is the relation between frequency of an applied voltage that is square wave, over an inductor, and the average current that would flow ...
0
votes
1answer
53 views
Frequency of NAND gate output signal
I have to square wave signals with the same frequency where one is delayed compared to the other.
Put two signals to the input of a NAND gate (two inputs).
Is there way (math, or some kinds of ...
0
votes
2answers
83 views
What does a RF wave carry? [closed]
Other than an AC (Alternating Current) can a RF wave carry anything else ? How can the energy a RF wave carry be measured ? Would the frequency of the wave be related to the transmitted energy of the ...
0
votes
0answers
35 views
FDS100 Photodiode Receiver Circuit
Has anyone tried using the FDS100 (or similar photodiode) for an application with an input signal frequency (laser on/off) in the MHz range? Connecting the circuit in Thorlabs' recommended layout ...
1
vote
1answer
584 views
I bought an air conditioner in Thailand rated 220v-240v, 50 Hz. What could happen if I use it in our country which uses 220v, 60 Hz? [closed]
I bought an air conditioner (split type) rated 220v-240v, 50 Hz. What could happen if I use it in our country which uses 220v, 60 Hz? A lead technician from a refrigerator and air conditioner shop ...
0
votes
2answers
40 views
Why does the voltage output of a signal generator changes with its frequency setting?
I connected a signal generator to a 5.1 ohm resistor, which may be too low comparing to the internal resistance of the generator, so I got only several hundreds millivolts amplitude for frequencies ...
0
votes
0answers
27 views
How can I configure HFSS to analyze in frequency sweep?
I'm trying to generate a plot Gain(dB) vs Freq(MHz) with HFSS. I do know that it can be obtained clicking to "Create Far Field Report->Rectangular Plot" then select Phi and Theta, and all frequencies. ...
4
votes
3answers
491 views
How does an inductor block frequency?
I know the basics of self-inductance, and how an inductor creates a voltage/current that opposes the increase or decrease in current.
I can't find anything on how it reacts to/blocks certain ...
1
vote
2answers
75 views
Is it possible to convert a low frequency signal into a higher frequency signal?
I have a signal generator that has an adjustable frequency range that is below the required frequency that I need.
Is it possible to input a signal from my generator into a passive series RLC filter ...
1
vote
2answers
56 views
Approximate Gain vs Frequency Curve for an RC circuit
I'm trying to draw an approximate gain vs frequency curve for this RC circuit:
I can solve for specific points, i.e. when \$\omega=\frac{1}{RC}\$ the Gain scale will be at -3dB but I'm not sure ...
2
votes
1answer
68 views
Ultrasound transducer at different frequencies
An ultrasound transducer is specified to have two standard frequencies; 820 KHz, and 2.5 MHz, does this mean that any frequency in-between can be used?
If not, what would happen if a generated signal ...
1
vote
1answer
51 views
Piezo vibration sensor board negativ values
I have this piezo vibration sensor module from Grove: http://www.seeedstudio.com/wiki/Grove_-_Piezo_Vibration_Sensor
Using this sensor and an arduino device I want to measure two things:
amplitude ...
0
votes
1answer
37 views
The relation between a link speed and Fourier coefficients
I am reading Computer Networks by Tanenbaum and the the chapter about the physical link and there is an example that I don't understand.
The author states that given a bit rate of b bits/sec the ...
2
votes
1answer
35 views
Are there reasons besides audible noise to run a VFD at a higher carrier frequency?
VFDs - variable frequency (motor) drives - output a pulse-width-modulated carrier approximating a sine wave. The carrier frequency is typically variable. I've seen numbers as low as 1 kHz, and as high ...
3
votes
3answers
103 views
Design help! — Play a pure tone into a mic and depending on its frequency a specific LED will light up
I'm still new to electronics and am making this in order to learn more about circuit design and filters. I do not want to use microcontrollers. I want a purely analog solution.
I'm trying to make a ...
0
votes
0answers
39 views
How dimension a LC filter to pwm signal [duplicate]
Hello, as you can see in shecmatic , I am creating a PWM signal by comparing a sine wave (50Hz) and a triangular wave (10kHz) which is within the block "PWM(10khz).... in ordem to control a full ...
1
vote
2answers
98 views
PWM frequency and LC filter
I'm new here, I have some fairly basic doubt.
I am creating a PWM signal in MatLab by comparing a sine wave (50Hz) and a triangular wave (2kHz) .... So what is the PWM frequency will output?
After ...
3
votes
1answer
70 views
Why is my VHDL clock signal so far off from what I thought it would be?
I'm new to FPGA and VHDL. The following code was supposed to be 5MHz but I'm getting 4.167MHz on my scope.
The FPGA board I ...
0
votes
2answers
66 views
Inverter PWM frequency
I am making a modified sine wave inverter. The PWM wave is generated, switched using transistors, and then passed through a transformer. What is the PWM frequency required to generate a modified sine ...
1
vote
1answer
91 views
Why are properties of components often given at 1 kHz?
The title pretty much sums it up. Aside from DC, why are the properties of components often listed at 1 kHz? I keep hearing that it is a "standard", but why 1 kHz? This seems to be pretty common in ...
1
vote
1answer
76 views
Why two 2nd order filters have different roll off?
I have designed these two butterworth filter for 1.5k cutoff frequency. what it surprising me that roll off of first design is more than roll off of second design. According to me both are 2nd ...
-2
votes
1answer
73 views
Data rate 9600 bps given what is frequency?
It is said that 9600 bps is the data rate given and if each signal element represents 4 bits then what is frequency ??
What I did since each signal element represents 4 bits then in a second ...
0
votes
1answer
68 views
frequency divider by 42 with 50% duty cycle
I want to design a clock divider by 42 from flip flops. Is there a way to do that while still gets 50% duty cycle?
0
votes
1answer
78 views
Design challenge: Detect finger-to-finger touch with nothing in between
I'm trying to build something quite challenging and seem to be getting nowhere. Maybe you'll help. I'd like to detect a touch of two naked fingers with no materials or sensors in between (simple ...
1
vote
2answers
45 views
Linear operating range of an amplifier as a function of frequency
How does the linear operating range of an amplifier (the linear part of the function that describes Power Out vs. Power In), both in theory and in practice, vary with frequency? In other words, if I ...
3
votes
2answers
117 views
SYSTEMConfigPerformance not executing in PIC32
I have PIC32MX795F512L MCU and I am working on its UART communication. I have made the program and its working fine. I was ...
0
votes
1answer
53 views
Help understanding frequency calculation for VCO Schematic in LM13700 Datasheet
I am trying to work through the math of the following schematic pulled from the LM13700 datasheet:
I can certainly hook this up and mess with the values to change the frequency range to my liking ...
3
votes
3answers
344 views
How fast can a Transistor Switch?
An NPN Transistor can be made a switch by applying some power to the Base.
Is there a limit to how fast I can switch the Transistor On and Off? Or I can switch it on and off as fast as i can turn the ...
1
vote
0answers
30 views
Torque and Current Frequency Relationship in Lorentz force
Lorentz force equation shows us that current is proportional to the force. Is it safe to assume that the force generated by an AC current at 60Hz will always have the same frequency? In other words, ...
0
votes
1answer
65 views
Automotive alternator: zero crossing detection (frequency)
I need to detect voltage frequency of an automotive alternator (before rectification). Alternator is a 3-phase generator, I will be looking at one of the phases. The voltage frequency never exceeds ...
0
votes
1answer
46 views
how frequency affects performance
Can we use 60 Hz induction motor in 50 Hz Current Supply,
What are the possible failures can happen if we use the motor continuously under this circumstances.
-2
votes
1answer
69 views
What happens to a Sine wave in the frequency domain?
Say for eg.if we have a sinusoidal signal of
f = 1KHZ, VPP = 1V and Voffset = 0V
If I change my Offset Voltage from 0v to +5 V, What would be the effects in Time domain and frequency domain?
0
votes
1answer
59 views
How to set SD card clock frequency between 100 kHz - 400 kHz
I am interfacing a 32 GB microSD card with PIC32MX795F512L. I am following the examples provided in Lucio de Jasio's book.
As the author has described that to set a 250 kHz, they are ...
4
votes
4answers
358 views
Inductive reactance: frequency vs current. Why current goes to zero as frequency increases?
Suppose I have the circuit below with the frequency of the voltage source as a free parameter. Assuming the inductance is constant, the current flowing through the circuit shoud equal
$$I(f) = ...
1
vote
3answers
128 views
How to delay a “not gate oscillator” to make it run at a desired frequency?
I want to blink an led(0.75 seconds on and 0.75 seconds off) repeatedly. I was thinking of using an idea from a book called "But How Do It Know" by J. Clark Scott. A part of the book tries to explain ...
3
votes
9answers
391 views
How can I make a linearly tunable 50% duty astable multivibrator?
I want to make an astable multivibrator with a 50% duty cycle that can be tuned with a potentiometer for generating sound, so accuracy is desired.
My first thought was to build the standard one with ...
0
votes
4answers
153 views
AC Circuit + Parallel resonant band-stop filter
My EE book says about this circuit:
"The parallel LC components present a high impedance at resonant frequency, thereby blocking the signal from the load at that frequency. Conversely, it passes ...
0
votes
2answers
81 views
Analog Peak Filter
I'm currently working on a project building headphone and to had to build filters to cancel certain unwanted frequency. While researching and working on it, i came across a reference design which ...
1
vote
1answer
64 views
How to detect the changes in capacitor?
I have a capacitor in the picofarad range. That capacitor will change slightly ±5 picofarad. How can I detect that change?
I used two parallel plates (about 5cm gap) that gives 18pF.
