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Some Simple FM Transmitters

Discussion in 'Electronic Projects' started by Iceman_Chris, Nov 28, 2004.

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  1. Iceman_Chris

    Iceman_Chris New Member

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    I have quite a few so I decided to post many FM transmitter schematics.
     

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  2. kinjalgp

    kinjalgp Active Member

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    What about component values in the first schematic? "fmtrans2.gif"
     
  3. Iceman_Chris

    Iceman_Chris New Member

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    got them here somewhere...

    sorry about that...

    I got them somewhere here in about 50 megs worth of my personal garbage :? .
     
  4. dave

    Dave New Member

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  5. yungboss

    yungboss New Member

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    would it reaaly work if i connect it

    will this circuit design work if i go by your diagram?(the 2nd one)
     
  6. Iceman_Chris

    Iceman_Chris New Member

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    it should work as long as you follow the schematic closely and dont use a breadboard or stripboard

    use a pcb as the metal tracks breadboard and stripboard tend to act like many little capacitors, causing the radio to not work properly

    i hope that answers your question...
     
  7. mstechca

    mstechca New Member

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    Why do you care?
    Isnt the last circuit an AM receiver? I found it from CXI (Circuit exchange Intertnational) schematics.

    I recommend the 2nd circuit as an FM transmitter since it worked for me.
     
  8. Iceman_Chris

    Iceman_Chris New Member

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    yes it is lol...

    i have about 200 circuit schematics and about 120 of my own...gets mixed up alot...

    sry
     
  9. mstechca

    mstechca New Member

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    how do I calculate the bandwidth each transmitter delivers?
     
  10. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    I don't think you do, although suprisingly effective these types of transmitters are horribly crude - the more audio you put into them the higher the deviation of the output. It's not even a 'proper' FM modulation, I suspect you probably get as much AM as FM from them?.

    But any FM transmitters bandwidth is dependent on the amount of modulation applied - that's why broadcasters have serious limiters on their inputs!.
     
  11. mstechca

    mstechca New Member

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    ok :eek:

    how do I calculate the modulation level, and what are the units for the modulation level?
     
  12. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    Again, I don't see how you can, the modulation action in these crude transmitters is obscure in how it works, I see no way to calculate it.

    For an FM transmitter I imagine it would be measured in 'KHz per volt', or something similar?. For an AM transmitter it's in percent.

    Why do you want to calculate/measure this anyway?.
     
  13. mstechca

    mstechca New Member

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    I want to be able to make my own wireless network between two computers, and further learn radio electronics.
     
  14. Nigel Goodwin

    Nigel Goodwin Super Moderator Most Helpful Member

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    This isn't the way to do it!.

    It's far too low a frequency, and far too low a potential data rate for networking.

    Wireless network components cost very little these days and give excellent speed and performance - you would probably spend more building crude radio systems for a system more than a thousand times slower!.
     
  15. Iceman_Chris

    Iceman_Chris New Member

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    these are not for those kind of uses.
    these are simply the basic design for audio transmitters, not data transmitters.

    like nigel said, they are too low of a frequency and would get far too much interference and data loss. if you are really interested in learning about radios, the best way would probably be to buy a good-quality diy kit

    i hope that helps...
     
  16. aravind c k

    aravind c k New Member

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  17. chefach

    chefach New Member

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    Hi can you pleaze post me or send me to the email dor.mark@gmail.com
    the most simple FM stereo transmiter?

    I'll be thankfull :)
     
  18. audioguru

    audioguru Well-Known Member Most Helpful Member

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    Enter in a search on Google: Stereo Micromitter and the 1st link will be to Silicon Chip magazine's stereo FM transmitter project.
    I've seen finished ones in stores. For only $25.00CAN on sale. They have an RF attenuator on the output which can easily be bypassed for greater range. :lol:
     
  19. taaz

    taaz New Member

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    any one can tell me how to built FM reciever
     
  20. taaz

    taaz New Member

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    Hi can you plz post me or send me to the email taaz111@yahoo.co.in
    the most simple FM receiver
     
  21. blueroomelectronics

    blueroomelectronics Well-Known Member

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    Couldn't find anything on the internet? Did you Google it?
     
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