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Amplifying RF Signal Advice

  1. Jan 31, 2013 #1

    I'm an A Level student at college (take it easy, I'm still very much learning) and I'm currently looking into a small demonstration of resonant inductive coupling, or "Wireless Electricity".. I'm fairly confident with the theory behind it and the majority of the build for it. However, one thing I'm struggling with is generating the sine wave signal for it.

    The frequency needs to be somewhere in the 100's of kHz to 10 Mhz range, and I'm somewhat flexible with the actual value though I'd rather not be constrained too much. All the signal generators I have access to simply do not go up to these frequencies so without spending a pretty sizeable chunk of money (which isn't an option) on a signal generator that does go up to those frequencies, I'm looking for an alternate solution.

    I've found various places selling signal generator modules for around £20 online, which granted, I accept won't exactly be the quality of a system costing more than 10 times the price, but they seem like my only option. One pitfall of the modules is that they only output a low voltage, typically well below 10V peak to peak which by the time it gets to the load on the other end of the system, will most likely be well below what is required.

    Really, I need an amplifier for the signal, perhaps even only to double the voltage to around 20V but I'm really struggling to find something suitable. It would have to be somewhat independent of the frequency bearing in mind the ranges I specified above and again, I don't have a particularly high budget for this (though I'd appreciate any suggestions even to just give me an idea what I'm looking for). I'm not really looking to build something as that detracts a little from what I'm actually trying to achieve and the timescale in which I'd like to have it up and running by.

    If anyone has any suggestions of ideal equipment I could use, I'd really appreciate the input.

  2. jcsd
  3. Jan 31, 2013 #2


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    Staff: Mentor

    Welcome to the PF.

    Mini-Circuits makes good amplifier modules. Check out their website to see if anything matches your requirements:

    http://www.minicircuits.com/products/Amplifiers.shtml [Broken]

    Also, part of any project like this is to understand the RF Band Plan for any frequencies that you are working with, and be sure that you do not radiate EM away from your setup that can cause interference with licensed radio bands. AM radio is around 1MHz, and other bands are around 10MHz. Depending on the size/configuration of your setup and the frequency that you choose, you may end up with a radiated EMI problem (a knock at your door by the FCC or a local HAM who works with the FCC finding interference sources).
    Last edited by a moderator: May 6, 2017
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