Electromagnetism question (specifically receivers)

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    Electromagnetism
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Discussion Overview

The discussion revolves around the functioning of receivers in electromagnetism, specifically how they filter and accept certain frequencies while ignoring others. Participants explore concepts related to radio frequency signals, tuning mechanisms, and the role of components like LC circuits in receivers.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses confusion about how receivers manage to avoid being overwhelmed by various frequencies and how they selectively accept certain frequencies.
  • Another participant explains that a radio receiver filters out unwanted signals and amplifies only the desired frequency band, noting the potential for interference from other stations on the same frequency.
  • A participant mentions the role of an LC circuit as a crucial component in radio receivers, linking to external resources for further reading.
  • There is a correction regarding the generation of frequency in a wire, clarifying that it is the AC/RF generator that supplies energy at a specific frequency, not the wire itself.
  • Further clarification is provided that electromagnetic fields from nearby waves also contribute to the frequency experienced by the wire in a receiving context.

Areas of Agreement / Disagreement

Participants do not reach a consensus on all points, particularly regarding the initial understanding of how frequencies are generated and received. Some points are clarified, but confusion remains about the overall functioning of receivers.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about frequency generation and the specifics of receiver operation, which may depend on definitions and context not fully explored in the thread.

revv
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I have trouble understanding how a receiver doesn't get bombarded with frequencies... and exactly how does a receiver only "accept" certain frequencies?

I understand if you send energy(or electricity) through a copper wire (and other types of metals) it makes a frequency with certain hertz (correct me if I am wrong please)

I might be completely interpreting everything I just said wrong but hopefully it makes sense.

thank you for taking the time to read and reply to me
 
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If you stick a wire up in the air, all the passing Radio Frequency signals will add up to induce a small voltage to appear at the output lead. The function of a Radio Receiver is that it filters out all those signals that it doeans't want and only amplifies the band of frequencies that the wanted signal occupies. When you 'tune' a receiver, you are adjusting the filter frequency so you pick up only the signal you want. It is always possible that there will be interference in the wanted channel when there is another station on the same frequency.
 
Thank you again for taking the time to reply to me sophie I really appreciate it. I will try to read more about this I still don't quite understand but if I ever have more questions I will come back to this thread!
 
revv said:
I understand if you send energy(or electricity) through a copper wire (and other types of metals) it makes a frequency with certain hertz (correct me if I am wrong please)

not quite

The copper wire is just that, a bit of wire.
it's the AC/RF generator attached to the wire, that is supplying the energy at a specific frequency
 
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davenn said:
t's the AC/RF generator attached to the wire, that is supplying the energy at a specific frequency
Or the EM fields of the waves in the vicinity of the wire.
 
sophiecentaur said:
Or the EM fields of the waves in the vicinity of the wire.

yup, for the receive situation
 

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