Electromagnetism question (specifically receivers)

  • Context: Undergrad 
  • Thread starter Thread starter revv
  • Start date Start date
  • Tags Tags
    Electromagnetism
Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
6 replies · 1K views
revv
Messages
55
Reaction score
9
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
 
Physics news on Phys.org
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
 
  • Like
Likes   Reactions: sophiecentaur
sophiecentaur said:
Or the EM fields of the waves in the vicinity of the wire.

yup, for the receive situation