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Amplitude based energy to frequency based energy converter

  1. May 8, 2010 #1
    i need to know if i can convert the high amplitude low frequency based energy to low amplitude high frequency energy based energy in both the case over all power should remain constant.And frequency should be in the range of VHF not in microwave range.
     
  2. jcsd
  3. May 8, 2010 #2

    vk6kro

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    Maybe you could explain what you are trying to do.

    What power levels and frequencies are you talking about?
     
  4. May 8, 2010 #3
    You can use the Linear Technology LTC3588 self-powered "energy harvesting" IC to convert low frequency mechanical vibrations (using a piezoelectric crystal) to dc power for a VHF oscillator. See

    http://cds.linear.com/docs/Datasheet/35881f.pdf [Broken]

    Bob S
     
    Last edited by a moderator: May 4, 2017
  5. May 8, 2010 #4

    dlgoff

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    I don't want to hijack this thread, but a quick question. Where the heck did you find such a device? Have you used it? Cute little thing.
     
    Last edited by a moderator: May 4, 2017
  6. May 9, 2010 #5
    20-30W and sufficiently high frequency as per my power requirement.Probably It will be in the range between VHF & UHF.And i m trying convert amplitude based electrical energy to frequency based electrical energy i.e. 120V & 60Hz to some mV & some GHz or MHz.
     
    Last edited: May 9, 2010
  7. May 9, 2010 #6

    vk6kro

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    OK, I'll make a guess and you tell me if it is what you want?

    Do you want to modulate a VHF transmitter with a low frequency signal, like voice from a microphone?

    If that is not it, what is the frequency of your input and where is it coming from?
     
  8. May 9, 2010 #7
    You are near to that but the power involved in this case is much higher then the low frequency microphone input.My input is electrical power of nearly 20-30W.and frequency would be the same of our a.c. supply 50 60Hz.I want to convert a.c. sinusoidal waves of 50 60 Hz with amplitude in terms of volts to high frequency waves(in the range of Hundreds of MHz to some GHz) with amplitude in terms of millivolts.Now u got it what i am trying to convey?
     
    Last edited: May 9, 2010
  9. May 9, 2010 #8

    vk6kro

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    So, you are looking for an RF signal generator that has a mains power supply?

    This would take your mains voltage at quite small power and turn it into a variable frequency output which was adjustable in amplitude.

    Good ones operate up to the GHz range, but quite cheap ones are available that produce frequencies up to the low VHF range.
     
  10. May 9, 2010 #9
    Power should remain constant but in input power is in form of amplitude but at the output the same power should be in the form of frequency.I am interested in transmitting the energy.The electrical energy in the form of em waves energy for wireless transmission.
     
  11. May 9, 2010 #10

    vk6kro

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    Do you want to frequency modulate a RF signal generator according to an input signal? That would give constant power out, but at variable frequencies, depending on the input data.

    Maybe someone else can see what you are asking.

    Please EXPLAIN where your input signal is coming from, what frequency it has, and what voltage it has, and then explain what you want to achieve by doing this.

    Treat it like a school laboratory experiment. Draw diagrams and give a clear, exact description of what you intend to do and which part of it you are unable to do.
     
    Last edited: May 9, 2010
  12. May 10, 2010 #11
    The LTC3588 "Energy Harvester" chip is the lead article in the free LT Journal of Analog Innovation (April 2010):

    http://cds.linear.com/docs/LT%20Magazine/LTJournal-V20N1-00-Cover-LTC3588-1-MichaelWhitaker.pdf [Broken]

    I have not used it (yet).

    Bob S
     
    Last edited by a moderator: May 4, 2017
  13. May 10, 2010 #12
    But it is using the ambiance energy i want use the electrical energy electrical power and i want transmit that power without wires.so for that i need to convert this electrical amplitude based energy to frequency based energy in the form of em waves.
     
  14. May 10, 2010 #13
    Are you attempting to operate electronic equipment without any wires?
    To transmit 20 or 30 watts through the air as RF is usually too involved/inefficient to be practical.

    Batteries are usually used.

    An extremely powerful light and solar cells can be used.

    Isolation transformers are probably the most commonly used method.

    Using a motor with isolated drive shaft and a generator is another approach.
     
  15. May 10, 2010 #14
    Efficiency,I'll take care of that factor.And my goal is not to operate electronic equip my goal is to transmit electricity energy with out wires and that also with high frequency em waves only of VHF or UHF range.so is there any method device to produce such high frequency waves using electrical power input.Em waves should have the same power that of the electrical power.Output power should be in the form of high frequency.power stored in the form of frequency.
     
    Last edited: May 10, 2010
  16. May 10, 2010 #15
    So nobody has told this poor soul yet, that power is amplitude squared no matter the frequency?
     
  17. May 10, 2010 #16
    Radio Amateurs transmit power all the time.
    See the ARRL Handbook for Radio Amateurs
    or
    Radio Handbook by William I. Orr, W6SAI

    You will probably need a Amateur Radio License. (If in the USA to operate the ransmitter)
    You will probably also need a radio station license.

    In conclusion, for nearly all purposes, this is not a practical way to transmit energy.
     
  18. May 10, 2010 #17
    In the case of em waves power solely depends on the frequency.The higher the frequency the higher the energy of the em waves and higher the power they carry.you are not aware of wireless electricity development so you are talking like this dude.
     
  19. May 10, 2010 #18
    Thank you very much.I know its not practical right now but making impossible looking things possible is the real challenge man and i am gonna accept that challenge.And for that i need help from people like you.And i am going to do this at very small experimental level only not at commercial level right now.Do i still require the things u mentioned?You were saying that batteries are use instead of this stuff but battery get discharged very often so this thing i m trying to make is just to charge those battery with wireless power transmission.
     
  20. May 11, 2010 #19
    This is false. The energy quantizes in photons of an energy dependent on the frequency. The total energy (and thus the number of transmitted photons) is still proportional to the amplitude squared.

    In plane waves E is proportional to B so the pointing vectors absolute value
    [TEX]P=\left| \vec{S} \right| = \vec{B} \times \vec{E}[/TEX]
    is proportional to [tex]E^2[/tex]

    No, I have a degree in physics. That's why I am talking like this, dude.
     
  21. May 11, 2010 #20
    I appreciate your knowledge and accept my ignorance.i need your help.For high power transmission can i use high frequency waves?as they are carrying more energy per photon?you see em waves used for radio transmission can carry very little energy on the other hand microwave can carry large amount of energy.so the energy em waves carry(per photon) depends up on its frequency or not?
     
  22. May 11, 2010 #21
    And in frequency modulation when the amplitude of modulating signal goes high the frequency of modulated signal is very high or getting higher during that period of time.whts this?it doesn't mean that high amplitude based energy is converted in to high frequency based energy?i know in that case energy is not the concern waveform is the matter of concern.But still energy is stored relatively of very small amount.is it like that?Give me your view on this.
     
  23. May 12, 2010 #22
    Asking if you can transmit more Energy with higher frequencies is like asking if $1000 is worth more if you have it in $100 bills or $20 bills. I really doesn't matter. Just some frequencies are very hard to handle, so if you want to experiment go for amateur radio equipment.

    In frequency modulation higher power of your input signal does indeed get converted into higher frequencies, but this power is all burned in the input stage of your transmitter. The amplitude and thus the power of the radio signal stays the same. The receiver does all the work and pulls more energy from the battery if it receives a faster signal.
     
  24. May 13, 2010 #23
    Thanks i am making this thing not for regular power transmission but for battery charging purpose of mobiles laptops etc.I have some ideas to improve its efficiency so that it can be employed for this purpose with some what more efficiency.I m just trying to initiate a new thing may be the next generation will make it more practical with their new ideas.Am I thinking in a wrong way?
     
  25. May 13, 2010 #24
    Amateur radio equipment are capable of producing and transmitting such high frequency.waves carrying power?


    So you agree that high power can be converted into high frequencies.Why this all power is burned in the input stage of transmitter tell me the reason of this phenomena.Is there any way to prevent this power from getting burned?
     
  26. May 13, 2010 #25
    How often do I need to say this? Frequency doesn't matter that much. Look what you can do with 60Hz:
    http://www.scienceprog.com/the-bright-field-with-thousands-of-fluorescent-lights/

    Amateur radio equipment can produce radio waves. The amplifiers and antennas are designed for a certain power. If you increase the output power, with an amplifier you can transmit any amount of power that you want, but this is usually illegal because you disturb other equipment.

    The last thing I'll say about frequency modulation: The transmitter is designed to emit higher frequencies for higher input power. It does not "convert" the energy into frequency. Imagine you have a friend turn on a vacuum cleaner whenever you light a flashlight. Would you say, that the flash light's light is converted to 230 Volts to power the vacuum cleaner?
    These processes cannot be inverted. Another example would be that you have a little device that shines a light when there is high tide, do you thing you could use the device in reverse so you could cause a high tide when you shine light on it? So energy to frequency is one way, that's it.

    For battery charging radio waves are a waste of power. Near field effects like an induction cooker are much better, because they don't radiate. You are not going to get anywhere unless you spend at least half a year building amateur radio equipment or your own transformers, or visit some courses about these things.
     
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