What is Radio frequency: Definition and 45 Discussions

Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around 20 kHz to around 300 GHz. This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies; these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. Different sources specify different upper and lower bounds for the frequency range.

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  1. T

    Studying Critique My Self-Study Schedule (Signal Processing & RF Electronics)

    Hello everybody. I have already graduated I am currently in training at work which I am required to finish intensive courses. So I will start when it's completed. My interests are in Signal Processing & RF Electronics which you could tell by the study plan I created. I will be taking a slow...
  2. A

    Specific Absorption Rate(SAR) - caused from radio frequency from mobile phones

    Why SAR value at body is allways higher than at head?
  3. th078

    Radio frequency shielding for Raspberry Pi Zero

    So I'm trying to put together a Pi Zero mini computer to use for security-oriented applications, for example encrypting/decrypting messages, working with encryption keys, etc. It's cheap, very small and thus easy to carry around. However, I'm not entirely comfortable with the presence of the...
  4. T

    Plasma ball radio-frequency energy

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  5. G

    Radio Frequency Acceleration in Particle Accelerators

    So, I've been really interested in Particle Physics since 6th grade when I did a project on particle accelerators. I understand most of it, except for one thing, the radio frequency cavities which are used for acceleration. I just want to ask, how do the Superconducting Radio Frequency Cavities...
  6. OldWorldBlues

    Easy way to calculate losses for re-purposing a transformer?

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  7. C

    Creating a Multi-Radio Wave Demonstration: How to Find the Right Machine

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  8. R

    I Why don't we ever hear about low-frequency photons?

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  9. T

    Can a radio frequency be lowered by a passive circuit?

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  10. R

    Counting clicks (signals) at a radio frequency receoved by a shortwave radio

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  11. Plat

    How are RF harmonics affected by the shape of a waveform?

    How can the power/amplitude of a particular RF harmonic be calculated? I would assume it is some well-defined fraction of the amplitude of the main frequency? Do RF harmonics from a square-wave drive appear only on the even, odd, or both, multiples of the base frequency? How do high-frequency...
  12. R

    Modern usage of non-navigational radio beacons

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  13. I

    Determining the Correct Radio Frequency

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  14. Misha Kuznetsov

    Radio Frequency Bioluminescence

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  15. G

    What Forces Cause Rotational Emissions?

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  16. K

    Logitech X-530 - AM radio frequency

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  17. J

    RF Energy Harvester: Villard Circuit, Supercapacitor 3.7V 2000mAh

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  18. J

    Can a 0.33 Farad 5 Volt Supercapacitor Charge a 3.7V 2000mAh Mobile Battery?

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  19. H Smith 94

    Understanding propagation loss: What does this output mean?

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  20. H Smith 94

    How is radio wave propagation modelled in seawater?

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  21. P

    Quantum fluctuations at radio frequencies

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  22. S

    How Much Power Can a Coaxial Cable Transmit Before Breakdown?

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  23. E

    Radio Frequency Interference in Cell Phone

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  24. J

    Medical Electrophysiology Radio frequency Ablation Question

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  25. T

    Radio frequency amplifier and error rate

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  26. G

    Radio Frequency Interference (RFI)

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  27. jaketodd

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  28. S

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  29. T

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  30. V

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  31. V

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  32. S

    Construction Cranes Radio Frequency Induction

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  33. J

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  34. S

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  35. R

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  36. H

    Radio Frequency and electrical signals

    "Radio frequency (RF) is a rate of oscillation in the range of about 30 kHz to 300 GHz, which corresponds to the frequency of electrical signals normally used to produce and detect radio waves." - Quoted from Wikipedia. How can electrical signals be used to produce and detect radio waves...
  37. S

    Radio Frequency Quadrupole Linac Question

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  38. J

    Best Radio Frequency AM/FM radio

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  39. T

    Radio Frequency Photons / Electromagnetic Radiation Question

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  40. D

    Radio frequency selection problem

    Hello everybody. As I'm new here, maybe someone can help or direct me to other resources that will assist in my investigation. I am looking for information that can help me select the proper radio frequency for use in a new project. The following is an overview of the project and the...
  41. S

    Convert radio frequency to temperature

    Hello, Is there a formula to convert a certain radio frequency to temperature? Thanks.
  42. P

    Curious Radio Frequency Blocked with Lead?

    Hi all, I'm now very busy trying to findout how to block external RF at my apartment room. I'm on 23rd floor. A huge radio boardcasting tower (714KHz, 90MHz) is just 20 meters away running along with my building. It's higher than 25 floors. I know that many GROUNDED conductive surface can...
  43. S

    Radio Frequency Acceleration Scheme?

    Hello! I'm reading into the LHC and the "bunch structure", and I'm confused in general, and I think knowing what the radio frequency acceleration scheme is might help?! As in, how does it work? And does it actually use radio waves? Any help would be greatly appreciated! Thanks, Samantha
  44. B

    Exploring Radio Frequency Imaging: Applications & Technical Aspects

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  45. R

    RF Engineering: Exploring the Science of Radio Frequency Technology

    What is RF engineering?
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