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Questions tagged [frequency]

How many times something happens per second, measured in Hz (Hertz).

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0answers
38 views

Need help with low-frequecy transmitter circuit [on hold]

For this project I am trying to replicate keyfob security system used in modern cars. I need to generate 125khz magnetic field, so that a tag could recognize it and communicate back at higher ...
0
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2answers
34 views

Can MCPCBs be used for audio frequency and/or MCU clock frequency applications?

For purely aesthetic reasons1, not for heat dissipation, I am contemplating using MCPCBs for these two applications: Audio frequency circuits, such as a Baby 8 sequencer, Atari Punk console, ...
0
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1answer
28 views

SIMPLE digital control over 555 timer frequency and PWM?

I'm looking to create a sound generator with only simple ICs and components. I believe the 555 timer IC is a good candidate to be at the core of it, but I cannot for the life of me find out how best ...
2
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2answers
72 views

Crockcroft-Walton Voltage Multiplier Large Voltage Loss

I have a CW voltage multiplier that uses 30kV, 1nF capacitors and doubled 20kV, 5mA, 100ns diodes (for a total of 40kV). My ac source is a sine wave (viewed on the primary side of the transformer ...
-1
votes
1answer
33 views

producing a continuous sound using a timer

I'm looking to produce a pure sound on one frequency to be played via a timer to come on at intervals over a six week period. this is for an undergrad dissertation. would an arduino work and could it ...
1
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0answers
80 views

How can I change a DC current to a 1.7/2.4 MHz AC current for piezoelectric device

I would like to start by saying my experience in electronics is very limited and I will include pictures of everything. I am, however, trying to assemble a device which puts a current through a ...
0
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2answers
41 views

Pulse width for mark pulse

What is the pulse width for the mark pulse in an equal mark to space ratio pulse train operating at a repetition frequency of 5 MHz? The answer is suppose to be 100 ns .But I didn't understand how to ...
0
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0answers
36 views

PIC I2C clock related problem

I am trying to make an I2C communication with a device by using PIC18F26K83. I use 8 MHz MCU clock. While trying to set I2C clock these options: Use 8 MHz MCU clock & HFINTOSC for I2CxCLK ...
0
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0answers
35 views

In need of help to figure out why my 4046. demodulator circuit simulation is giving me errors

I’m currently doing a project on FM modulation and demodulation and on my proteus simulation I just can’t figure out how to do away with the two errors I keep getting. Here are the images of my ...
0
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0answers
49 views

Focusing on Frequencies with Guitar Pedal Capacitors

I just built my first guitar pedal (a Bazz Fuss fuzz pedal), and now I'm messing around with the electronics a little bit. I was just wondering how I could target specific frequencies with the pedal. ...
0
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3answers
81 views

Frequency circuit diagram

I have designed a frequency counter circuit diagram. See below. Now I am stuck on the part to wire up the decimal point in my circuit. The one that's the LED beside the 7 segment display. Do let me ...
0
votes
1answer
68 views

Minimum Effort to Run a 1100W Hot Air Brush from America to Japan?

I'm entertaining an idea of making a small power supply to get a certain hot air brush (For hair styling) to function on the Japanese power grid. I like this hot air brush that runs only on 120V/60Hz ...
1
vote
1answer
92 views

Are my calculations wrong?

So I'm trying to make relatively a large square coil antenna that will operate at 125kHz frequency. The width and height of antenna are 300mm (30cm) and wire diameter is AWG24 (0.51mm) and I'd like ...
0
votes
1answer
36 views

Not full-wave signal transmission?

Is it possible to transmit half-wave signals repetitively, like repetitive "north" magnetic fields like going from 0-1 Gauss "north" and repeat however many times per second without going 0-north-0-...
-2
votes
3answers
188 views

How to find the frequency of any device? [closed]

Are there devices which can figure out at what frequency every device transmitting radio frequencies operate at precisely? Say from a high of 2.4 GHz microwave to a low of 402 Hz pacemaker.
1
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2answers
93 views

Converting a variable frequency to TTL HIGH and LOW levels, based on a fixed (possible non-fixed?) frequency

I have a square output from an LM324 op-amp (0 and 5 volts) which has a frequency between 1 to 500 Hz (yes, low frequencies). I would like to find a simple way to have HIGH TTL signal when it is over ...
0
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0answers
30 views

Cheap RF 433.92MHz design, PCB track antenna [duplicate]

I'm doing a RF remote control project using a PCB with microcontroller and with simple onboard antenna layout as transmitter and a 433.92MHz receiver RWS-371F-6 model. Here is the datasheet of the ...
0
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0answers
24 views

Frequency Modulator with sinusoidal output

I am creating a frequency modulator, all the circuits that I have looked so far on the internet are generating a Pulse wave or a Triangular wave output, so if you guys can help me to create a circuit ...
10
votes
4answers
911 views

How is it possible to drive VGA displays at such high pixel clock frequencies?

I'm working on a digital circuit using discrete components to drive a 640x480 VGA display in a 80x30 text mode. For a 640x480 display, the pixel clock is 25.175MHz, which has a period around 40ns. I ...
2
votes
3answers
98 views

Why is the output frequency of the zero crossing detector (square wave generator) double that of the input signal?

I have built a zero crossing detector that acts as a square wave generator according to the circuit diagram shown. It is connected to a potential transformer. The output from the potential ...
0
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0answers
21 views

Uncertainty in current values of Power HD digital servo motor

In a project, we want to lift the load of 5 kg on the ground to half a meter. For this purpose, we use a 360-degree rotating PowerHD digital servo motor with a stall torque of 20 kg / cm. Motor ...
0
votes
1answer
52 views

beat frequency oscillator

I'm a new student in electrical engineering. I'm trying to make a BFO (Beat Frequency Oscillator) circuit for my university project. I didn't understand the duty of 3rd transistor and capacitors ...
0
votes
1answer
49 views

Baud rate for Square Wave data signal via UART if frequency is given

I was trying to solve the 2013 paper set by ISRO for electrical engineers. Question no 13 made me confused. So since Idle in UART is usually high and start bit is low, we can find the 8 bit data ...
1
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4answers
152 views

Using enameled copper wire as a capacitor for measuring water level in a tank?

I'm trying to make a capacitive water level sensor using two enameled copper wires used in transformers. I've used sanitary silicone to insulate the bottoms of the wires. (Coating is insulated by ...
0
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0answers
26 views

how to use the Vpp in this case?

in this exercise i thought i would approach it by finding the transfer function and i did find the transfer function by using a voltage divider equation, the problem im facing is that i don't have ...
0
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2answers
49 views

Frequency of AC for electronic devices

I was wondering why using different AC frequency makes some devises not working. I found that I do not need to adjust frequency for using electric heat or electromagnetic wave such as ・rice cooker ・...
0
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0answers
35 views

BLDC hoverboard motor with no specifications

I have this kind of motor but I can not find any electrical specifications about it. All I know is that is a 36V,250W BLDC motor. How can I determine the number of poles, the coil resistance/...
0
votes
1answer
54 views

Can you make an electric gamma ray emmiter by adding up frequencies with freq. mixers up until you reach gamma ray herz quantities?

I just thought this up. Theoretically if you can add freq numbers you can get to large quantities like in a calculator, only this time mixing electric frequencies using amounts of circuitry right? Is ...
0
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0answers
27 views

Choosing a position sensor (encoder) and obtaining velocity from it

How do I know how many counts per revolution I need for an encoder for my application? I need to be able to accurately capture a 1000 Hz signal on an input side running from 1-133 rev/sec (60-8000 ...
0
votes
1answer
35 views

THINNET 10BASE2 Network using RG-58 Coaxial Cable operating frequecy?

I am trying to figure out what the signal frequency of a 10BASE2 network is. Specifically the frequency of the signal being carried over coaxial cable. Data transfer is 10Mbps and the network adapters ...
4
votes
1answer
95 views

What determines the frequency of network cable

You have Cat6, 23 AWG, rated for 250Mhz frequency. You then have Cat6a, 23 AWG, rated for 500Mhz. Both are unshielded. How is Cat6a able to transmit data at a higher frequency then its counter part? ...
2
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2answers
103 views

How to find the source of a noise in a particular band

The problem: The ADSL2+ service at home is not performing up to its potential. The modem is supposed to sync at 16 Mbps (downstream) but the it does only up to 11.5 Mbps. Using the diagnostic tools ...
0
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2answers
94 views

Using 120 VAC 60 Hz battery charger with 50 Hz AC [closed]

I live in Australia (220-240 VAC, 50 Hz mains). On a recent trip to the United States (110-120 VAC, 60 Hz mains), I purchased some battery-powered tools that came with a charger. The charger has this ...
1
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2answers
56 views

Time to Frequency Transform - Where are the Initial Conditions?

In a circuit with sinusoidal source and charged capacitors and inductors we have initial conditions: $$u_{C}=u(0)+\frac{1}{C} \int_{t_{0}}^{t}i(\tau)d\tau$$ $$i_{L}=i(0)+\frac{1}{L} \int_{t_{0}}^{t}...
0
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2answers
54 views

Voltage Equation in Time Domain

When we describe a AC signal (voltage is this case) in time domain we use an equation something like this below: \$v(t) = V_m \mathrm{sin}(\omega 𝑡 + \phi)\$, where 𝜔 is the angular frequency of ...
0
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1answer
45 views

Generating square wave using NXP LPC1768?

I am reading a book that teaches about programming the LPC1768. I have the following exercise here: Using any digital output pin, write a program which outputs a square wave, by switching the output ...
0
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0answers
45 views

There exists 110v/60Hz motors as well 220/50Hz ac motors rating, what determines the voltage of an electric motor?

I have seen the Toms question and answers for what determines the voltage of an electric motor? None of the answers not fulfilling. I was not able to comment to get clarify my doubt, so I’m posting ...
8
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3answers
1k views

Estimate electrical frequency from clock shift

About 6 months ago I installed a solar power system with 2 Tesla Powerwalls for backup. Today, we got to test out the system with a power outage from an ice storm in the southeast. (We are still on ...
0
votes
1answer
47 views

Can I use the oscillation frequency equation for this circuit?

I'm not really sure if this is a question that can be answered so I'm sorry in advance if it isn't. I've just started doing electronics on a breadboard and I'm making a "Mini Strobe Light" from Jaycar'...
0
votes
1answer
37 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 ...
2
votes
1answer
96 views

Need some help designing a mains frequency converter (220v/50hz input, 220v/60hz output) for <$200USD

My main limitations here are with the amount of power needed, and of course the price. What I'm trying to do is to run a clothing dryer from the USA in another country, without burning out the drum ...
4
votes
4answers
541 views

Use audio frequency to light up multiple LEDs

Need some help here - I need to light up about 20 different LEDs based on the frequency input(200 Hz-20,000 Hz) Eg: The circuit should light up the 1'st LED when the input frequency is between ...
0
votes
0answers
72 views

Choosing an inductor for a bias T

I'm creating a Bias-T circuit for a certain application. When choosing my inductor to block my AC-signals I know for example the proper inductance to choose etc. However, what I am having trouble with ...
0
votes
1answer
67 views

From which circuit, I will be able to measure high frequency signal (in MHz) by using micro controller with 200 Ksps ADC?

I want to measure 20 MHz signal by using microcontroller with 12 bit ADC And 200 Ksps sampling rate. Which circuit should I design in order to measure it accurately?
0
votes
1answer
75 views

Ultrasonic transducer actual bandwidth for filtering

I have a pair of ultrasonic transducers with a "Thick Resonant frequency" of 975 kHz ±30kHz according to the data sheet. I did a frequency sweep test where I could see that they performed best at a ...
0
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1answer
151 views

Resistor's behaviour at high frequencies

Looking at the impedance vs. frequency graph 1) At low-frequencies Z=R and hence it would be a straight line. 2) For mid-frequencies, Z decreases possibly due to capacitance, but I'm not sure ...
0
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2answers
52 views

Passive Elements At high Frequency [parasitic effects]

What would the magnitude Response curve for a Resistor, Inductor and Capacitor look like [with parasitic effects not ideal components] ? From what I have gathered they would look something along the ...
0
votes
6answers
181 views

How do I set my speakers out of phase?

A little bit of context: I'm doing a project for my physics class where I could choose the topic, and I chose to do phases in sound and noise cancellation (wavelengths and frequencies). Essentially, ...
0
votes
1answer
85 views

Generating a realistic sine wave in MATLAB

I'm working on a simulation on MATLAB and I need a realistic sine wave which has harmonics. So I know there would be harmonics at 2f,3f... but I am not sure how to determine their amplitude. I tried ...
1
vote
1answer
58 views

How do we get the complex frequency of an exponentially damped sinusoidal function?

In my textbook, Engineering Circuit Analysis 8.Ed by William H. Hayt (Chapter 14, Section 14.1 page 536) I stumbled across a section explaining the complex frequency. The goal is to cover the concept ...