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A stereo FM receiver using the TEA5711 IC

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by radiomate, Jul 21, 2008.

  1. transistor495

    transistor495 Member Forum Supporter

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    You can try the basic principle as like here:

    varactor-drive-options.gif

    In the first image you can use the resistance as the wiper of a pot(say 10K according to input voltage and tuning range..do calculation) to change the reverse bias voltage across the varactor. Important thing is you need to isolate the bias voltage from entering the RF loop. A capacitor used here for isolation.
     
    Last edited: Nov 15, 2010
  2. audioguru

    audioguru Well-Known Member Most Helpful Member

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    The schematic of a manually tuned AM/FM radio on the datasheet shows a 4-gang tuning capacitor. Two of the gangs are for AM and two are for FM. Simply use a suitable varactor diode for each. The varactor diodes are tuned by changing the voltage with a pot of a regulated voltage.
     
  3. skldj

    skldj New Member

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    can you please tell me which one is better to use; tea5711 or sony cxa1538 . both are stereo ic. i have decided to build this receiver and find both ic are available in my area.
     
  4. dave

    Dave New Member

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  5. mvs sarma

    mvs sarma Well-Known Member

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    @skldj,
    why at all to build an FM radio when it can be bought dam cheap? your effort can better serve you, on any other gadget that could help your education and or hobby.
     
  6. skldj

    skldj New Member

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    it feels good when i do it by myself..
     

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  7. skldj

    skldj New Member

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    can i use 3n200 mosfet in place of bf981. because it is hard to find..
     

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  8. mvs sarma

    mvs sarma Well-Known Member

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    i can offer you BF998 in sot143 package
    check for datasheet

    they are cheaper
    take 10 at rs 10 each and postage extra
     
  9. skldj

    skldj New Member

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    wo
    wow! sound great to me. but where? R U SELLING IT?
     
  10. mvs sarma

    mvs sarma Well-Known Member

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    i had bought as a lot and used some. thus i can spare, I sent a pm to you.
     
  11. skldj

    skldj New Member

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  12. skldj

    skldj New Member

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    check your Email sir. thank you.
     
  13. mvs sarma

    mvs sarma Well-Known Member

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    ok, got the email too. Shall be dispatching on Monday by speed post. i would intimate you the tracking #.
     

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