TDA 7000 FM Radio - Help Please

Discussion in 'Homework Help' started by Shaira Rose, May 9, 2016.

  1. Shaira Rose

    Thread Starter New Member

    May 9, 2016
    10
    1
    Last edited by a moderator: May 9, 2016
  2. Shaira Rose

    Thread Starter New Member

    May 9, 2016
    10
    1
    Sir, does the circuit with adjustable coil works? I want to confirm it before I will make it on PCB thanks in advance guys! Sorry if I have to post here. This is the closest forum thread so far that relates on my problem.
     
  3. bertus

    Administrator

    Apr 5, 2008
    15,647
    2,346
    Hello,

    As the FM receiver has to work at about 100 Mhz, a breadboard will not work.
    In the datasheet there is a drawing of the PCB given.
    I also have attached a couple of application nots on the TDA7000.

    Bertus
     
  4. Shaira Rose

    Thread Starter New Member

    May 9, 2016
    10
    1
    Hi! I want to ask if this circuit works for my project in Communications. I need to make an FM radio and I want to know if this circuit will work. Thanks in advance.
     
  5. Shaira Rose

    Thread Starter New Member

    May 9, 2016
    10
    1
    Thanks for the fast response Sir Bertus! It helps a bit but can you confirm if this circuit will work as an fm receiver?
     
  6. Shaira Rose

    Thread Starter New Member

    May 9, 2016
    10
    1
    Okay Im sorry I understand the documents you just attached. Thanks Bertus!
     
  7. Shaira Rose

    Thread Starter New Member

    May 9, 2016
    10
    1
    Thanks again for the lightspeed response Bertus! But I'm curious about the values of Cs, Cv and Cp?
     
  8. RichardO

    Well-Known Member

    May 4, 2013
    1,235
    384
    Maybe, maybe not. You need to look at the manufacturers data sheets to see how they expect their devices to be used.

    Keep in mind that an FM radio operates at over 100 MHz. At this high frequency the physical construction of the circuit is tricky. Look at the data sheet for the TDA7000 for an example of a recommended PCB layout.
     
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  9. absf

    Senior Member

    Dec 29, 2010
    1,492
    372
    Here are more information on the TDA7000 FM radio here. There are PCB layout but not made. And I saw this a few years back so no idea if the kits is still available....

    Allen
     
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  10. vol_

    Member

    Dec 2, 2015
    93
    3
    From my experience with LM386 i wouldn't use it as an audio amplifier. The distortion is hand to hand with the IC.. At about 0.25W of output power it already gives its full distortion. More for this in its datasheet.
     
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  11. Shaira Rose

    Thread Starter New Member

    May 9, 2016
    10
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    Update: Ive made the circuit. But it has alot of noise. Maybe from the lm386 amplifier circuit. Or somewhere else in the circuitry. Any ideas guys?
     
  12. vol_

    Member

    Dec 2, 2015
    93
    3
    Are you running the circuit with 9V supply? LM386 will have noise for sure if you are. Try to omit the 4.7uF cap at pins 1 and 8. If there is no noise, LM386 gets the fault. If, then, gain is not enough for you, you can try two things or both (with the 4.7uF cap connected):

    6V supply and
    connecting LM386 in bass boost configuration.

    This is done connecting a 0.047uF or a 0.033uF capacitor in series with 10K resistor from pin 5 to pin 1.

    More about this in the end of LM386 Audio Amplifier Analysis.

    About TDA7000 i don't have a clue.

    Also try to describe the noise. Maybe someone with more experience will have a thought about the situation.

    Good to see a girl here. I don't like only men places.

    Cheers
     
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  13. Shaira Rose

    Thread Starter New Member

    May 9, 2016
    10
    1
    Thanks Im observig the noise through the oscilloscope to get some idea hoe to lessen it. This site is amazing for like a student me.
     
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