Questions tagged [high-frequency]
This tag marks questions related high frequency (radio) circuits.
524
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lowering voltage of high frequency signal
One of the parts I have is RAM (1.5V logic level).
The hardware communicating with it, is at a 1.8V logic level. The RAM signals are sent quickly - around 350-450Mhz.
So I am pretty sure I can't ...
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3
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How do I amplify a square wave pulse of 4 to 8 periods at 3.5 MHz from +-2V to +-60V or more?
I am working with ultrasound sensors optimized for 3.5 MHz signals, and I want to test these using my PicoScope 5000 with integrated signal generator. The PicoScope is able to generate arbitrary ...
2
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1
answer
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Low cost swarm positioning
I'm looking for a way to make a swarm of sensors know their position using low cost, low power system (ie ESP32.)
Requirement:
low cost per device
low power use on devices
1m accuracy is enough
2D ...
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2
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Why are high frequency signals not disturbed by stray fields?
I am trying to design an inductive position sensor based on a high-frequency signal.
It is mentioned that using high-frequency signals gives immunity towards stray magnetic fields.
Could anyone ...
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2
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RF 50 ohm dummy load PCB design
I am a rookie on both RF and PCB design and I am currently trying to do a 50 ohm 11 watt dummy load project for 100MHz-1GHz.
My calculations are done for the load but I have some questions about ...
2
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3
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341
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How do bypass capacitors recharge in high-frequency if the PCB can't deliver high-frequency currents?
I understand the whole theory behind bypass capacitors, how they are necessary to deliver high-frequency currents to the IC, as the PCB in general has high-inductance, thus high-impedance in high-...
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Reasons to use open circuit stub over a short circuit stub
I am having trouble with this question which states: suggest two reasons why the use of an open circuit stub might be preferable to a short circuit stub in microwave circuit design (microstrip)
Could ...
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121
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High Voltage Input
I am trying to make an high voltage arc generator which is approximately 2 kV output. Here I can easily drive this circuit with 19 volts (laptop battery). Just like in the circuit bellow, I connected ...
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Are there any effects on capacitance and inductance when operating at audio-frequency (i.e. 1kHz - 20kHz)?
At the moment, I study something about audio-frequency track circuits for railway applications and to understand its operation, an accurate model of such a circuit is required.
The circuit of audio-...
2
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1
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316
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A few questions about High Current on PCB
Original schematic:
My attempt at drawing the PCB:
The routes are drawn on both layers and the thickness of the power route is 600 mil(300 on top and 300 on bottom). It is necessary to support ~15A. ...
2
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3
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Why do current-feedback amplifiers have a higher bandwidth?
The advice when dealing with amplifying high-frequency signals always seems to be "use a current-feedback amplifier, not an op amp". (see 1, comments on 2, 3 and comments on its question) But why is ...
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481
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Low Voltage, High Frequency, High Amperage Power Supply Design
For an ongoing project of studying magnetic properties of various metals we need to use a power supply which can generate 25 V peak to peak, frequency 50- 500 kHz, 5A (PP) current. Frequency would be ...
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Oscilloscope Phase Shift
I have a university research that i am conducting right now. My objective, as a first step, would be to phase shift an NRZ signal at high frequencies >40GHz, assuming this signal is already locked ...
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Skin effect at high voltage
I recently made a slayer exciter circuit in order to determine the resonant frequency of my secondary coil of my yet to build SSTC.
When running the slayer exciter at 40V DC the circuit consumes ...
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Conductivity and high speed transmission using aluminium slip rings
So I came across a Persistence of Vision globe based video where a YouTuber he makes DIY slip rings to power and control some LEDs as seen in this picture:
My question is, given the high rate of data ...
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Measurement of transformer with a vector network analyser (VNA)
I have a planar air core (no ferrite) transformer in a PCB. I need to characterize the transfer function of this transformer from DC to 500 MHz using a vector network analyser (VNA).
My first ...
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2
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Capacitors choice for MHz resonance circuit
I am implementing a resonance circuit (for wireless charging) in MHz frequency (\$5-10~MHz\$) , and now, I am looking for suitable capacitors. The peak voltages and current through the capacitors are ...
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321
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What is the maximum frequency to use diodes for distortion?
What is the maximum frequency to use rectifier, Schottky or Zener diodes for cut off sin wave to square wave?
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Stream Audio and WebCam Video through Radio Frequency [closed]
I and my friend would love to make a better communication system between us since his internet connection is not the best and neither is mine. We are 20 km away from each other.
Our project is to ...
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2
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727
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How to drive an AD9850 at 100 kHz/s sweep using arduino or rasberry pi?
The basic problem I am interested in doing is using an ADXXX chip to make a linear frequency sweep through the HF bands, from 1-20 MHz. The sweep rate I would like to achieve is 100 kHz/s, which ...
0
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2
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789
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Why not using high frequency AC at homes?
I am a student at school but I learn electronics in parallel as I love it, all my knowledge came from the internet, so if there is a problem in my question please fix it.I came across something called ...
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571
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How does this electrical ballast need to be wired to the flyback transformer?
I just got myself a flyback transformer and an electrical ballast for fluorescent lamps as I heard those can be used together.
The electrical ballast is supposed to generate a high frequency which ...
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1
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Matching S22 with a metal plate at the output
So assume we have a highfrequency device which has a missmatch at S22. Some of my colleagues solder a little round metal plate, placed on top of the signalpath it self (shortly before the SMA ...
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141
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High frequency filter circuit design
I am a trying to design a design an Electrosurgical interference suppression (ESIS) protection layer to filter out high frequency noise caused by Electrosurgical equipment during surgery. I am using ...
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What is "tap line"?
I am reading this article (https://arxiv.org/ftp/arxiv/papers/1901/1901.02069.pdf) where I have come across this sentence: "we first designed a
parallel coupled Chebyshev bandpass filter as shown in ...
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2
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346
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Antenna Impedance Matching, 0 Ohm Response
I'm currently trying to match some SMD antenna breakout boards. These boards have one type of SMD antenna, footprints for an SMD pi network and a 50 Ohm cable as connection to my VNA.
Now the problem ...
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Conformal coating of UHF (radio frequency) circuitry 400 - 1000 MHz
Do you have experience applying conformal coating on UHF circuitry (ISM band)?
Are there known issues (e.g. degradation of UHF performance) which arise when coating UHF components like filters and ...
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594
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Choose RF block inductor value
I have inductor to block RF.
My signal is between 1 and 2 GhZ.
How should I choose the value of this inductor ?
1µH is enough ??
What are the other parameters to take care about ?
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193
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Pads reflecting in controlled impedance strip?
Background
I'm designing a controlled impedance line for a 1900MHz signal travelling between SIM7000A cellular chip and an antenna.
Question
Tuning circuits are recommended for antennas with series ...
0
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1
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59
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Help with analysis of a signal that generates high frequency
I am trying to understand this circuit:
In circle 1: I don't know why we make two capacitor in noise circuit, we can't do just one?
In circle 2: The tuned circuit consists of capacitor C1 and ...
2
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1
answer
513
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Ways to decrease TVS diode capacitance
I am currently working on high speed ethernet data line, and I wanted to know if there is a way to decrease TVS capacitance.
I thought of putting two TVS diodes in series to reduce capacitance.
...
2
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127
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Improve the frequency of Current Source Howland effect Op-Amp
I need help on a Howland Effect circuit with a current source purpose with an output of 600mA and a constant gain throughout a range of frequencies starting in 0Hz to 1Mhz. I am currently using an ...
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Why do microwave ovens use magnetrons?
With a lot of advancement in solid state electronics and signal manipulation, isn't it easier to simply take high amplitude signals with frequencies near 1 MHz and multiply the signals using diodes ...
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221
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Phase detection with non-ideal PFD
I'm trying to simulate for Phase Frequency Detector with the following implementation:
and inside NAND_PFD:
NOTE: the triangles on the right are inverters and not amplifiers.
I'm currently ...
3
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3
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826
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PCB design for 50MHz
I'm designing a rather big PCB which will have 64 nokia 5110 LCDs arranged in an 8x8 matrix and will all be controlled by a single microcontroller.
Each screen will have an 8-bit shift register as a ...
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140
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Power devices max voltage, current, power, speed, etc. .. ratings
I want to know how to get the real world or the most recent or the reliable information about power devices max ratings in volt, ampere, power, speed .. etc., parameters.
I found this picture that is ...
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Reduce Power of High frequency output signal (40khz)
I want to try and make the output power of the following driver board adjustable. At full power it runs at 100watt I. The board itself does not have an option to reduce the power output. The output ...
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763
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Is isolation required for MOSFET gate driver's and microprocessor's power supply?
I have designed a 62 W, 24 V to 5 V buck converter operating at 250 kHz.
I am using TI's UCC27200A gate driver and Infineon's Optimos 4.
The problem is that the driver doesn't have any kind of ...
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632
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Measuring the quality factor RLC circuit
I am trying to get the Q factor for this circuit but I don't know how to simulate it properly.
I did a frequency sweep from 1 Hz - 30 MHz.
The oscillating frequency is 16 MHz.
I can't get the ...
4
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1
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Inverter Circuit using IR2113, TLC555 and signal inverter IC
Input DC = 30V
operating frequency = 10kHz
problem =
When I am at the no-load condition at the output, only the oscilloscope is connected, I am receiving the proper output. But when I connect a load,...
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Why does the cable resistance jump from a low value to high value at a particular frequency?
I am not well versed with transmission line theory so if you can redirect me to relevant material I'd be grateful. So I used Agilent 4294A to find resistance of a 2 metre long shielded twisted pair ...
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0
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Decreasing phase noise of natural oscillators by passive resonant filter on-chip in the MHz regime
I was doing a literature research on microwave filters and to me it looks like passive SAW filters/resonators have the highest quality factor below 1.5 GHz, but with a high power loss. Coupled planar ...
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629
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FR-4 RF attenuation (when used as an enclosure)
I want to use a blank PCB (no copper) as a panel of an enclosure because it seems to be the cheapest way (Seeedstudio et al.) to have custom holes and cutouts.
I wonder if antennas placed behind such ...
4
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1
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382
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High Voltage Planar Transformers
I am designing a high voltage DC/DC converter that is for an aerospace application and therefore I am focusing on reducing the size and weight, so switching at a high frequency possibly integrating ...
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87
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Is the difference in trace lengths why my RTC isnt working?
I am using the PCF8523TS RTC with a 32.768 kHz Crystal. I have tested the smaller package which worked fine with the Adafruit module, but I can't seem to get it to work with the TS package. I either ...
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786
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Brushless motor back and high current and IC
I'm trying to replace the brain of my neato vacuum which is broken.
I've already repair a cleaning MOP but with this one I have a problem with the brushless motor which is throwing some party fun in ...
3
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2
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1k
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USB Routing: Switching layers during routing
I'm working on a standard 4 layer board that involves USB 3.0. I have to route the SS TX/RX pairs as well as D+/D- pairs across a 2.8" PCB. I have found multiple calculators that provide me the ...
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205
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Power amplifier design
For my research purpose, I am planning to design one power amplifier (basically, a current amplifier) with the following specification-
Frequency range: 0-100MHz (or at least 0-30MHz)
Output voltage: ...
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5
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247
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Why can't all data be sent across 4 wires?
I am aware that USB uses a positive, negative and D+/- wires in order to transmit data. The twisted pair are used to negate the effects of interference and electronic noise.
I also understand that a ...
5
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1
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Skin Effect of resistors
Skin effect of metallic conductors is well documented.
What about SMD resistors?
High values Vs low values? Above what frequencies would this be an issue?