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    Wi-Fi Beacon Photo or Plot?

    Please excuse the late reply. I am trying to understand the Wi-Fi signal structure, in particular the "beacon", and thought a screenshot of an actual signal would help. Does the beacon take the form of a 1) 100mS packet of data or 2) phase shift in data that recurs every 100mS? Would it look...
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    Wi-Fi Beacon Photo or Plot?

    Sorry. You've lost me there. I am interested in a screenshot of the actual Wi-Fi signal not a plot of its frequency spectrum.
  3. E

    Wi-Fi Beacon Photo or Plot?

    I searched the net yet again and can find nothing in the way of published images. My oscilloscope will not read that high. Can anyone please help?
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    Wi-Fi Beacon Photo or Plot?

    Can anyone provide an oscilloscope screenshot, or plotted output, that clearly shows several cycles of the 10Hz beacon as embedded within a Wi-Fi transmission?
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    Junction noise is sufficient randomness for my application. There are variables other than its frequency distribution that will be controlled. Yes, I know of someone who pointed a photocell at trees blowing in the wind to obtain a random signal. Lava lamps do the same. Noise can also be...
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    The depth of random modulation, relative levels of signals prior to mixing, etc.
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    Thank you. Those are both interesting circuits. The random LF noise source is certainly relevant to this thread. The quad LFO would make a great signal source for a rotational effect. To complete my project, I am hoping someone can suggest an IQ mixer IC that will operate at low frequency. Or...
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    Not sure why that would be bothering. The mixer is intended to "distort" the sine wave. It would still look sinusoidal in part, but with amplitude and phase changes as determined by the modulating random wave form. Can anyone recommend a mixer IC part that would be most suitable for this purpose?
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    Yes, but I would have to outsource the programming for anything like that. I would like to proceed more along the lines described by Nanren888. Might be of interest to some other analog fans here as well.
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    In dealing with natural phenomena, we very rarely see rectilinear wave forms. Assuming the pseudo random generator works well at ELF, then an I Q modulator does seem like the most viable option. In that case, phase modulation would be acceptable in lieu of FM. Can anyone recommend an IC that...
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    The circuit in the article that uses a CD4015 and CD4030 looks very promising. Would it be possible to clock it slow enough so that the pulses occur exclusively within the ELF domain? I have used analog filters on PWM signals before in audio applications.
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    The dominant "frequency" of the varying light needs to have a specifiable ELF component. As stated in my OP, all I want to do is randomise this in amplitude and frequency. For example, within a 10-50% deviation. For this reason, I would start with an ELF sine wave. No rectilinear functions in...
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    Software is frequently promoted as the "easy" answer. But I would need to write a program with variable parameters to accommodate a range of experimental conditions. Even then, there would be no ability to make gradual adjustments in real time while monitoring for effects. Hardware replication...
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    I was using a 20Hz sine wave as an example. I would like the circuit described to perform the same operation upon any signal fed into it. These would all be in the sub to low audio range. The "meandering sine wave" you refer to above is exactly what I am looking for. Think sunlight through...
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    How about a random noise source fed into a quadrature mixer along with the sine wave? If so, could you provide any further information on that type of circuit.
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    Analog Circuit to Randomly Modulate Amplitude and Frequency

    I have a 20Hz 2Vpp sine wave and would like to simultaneously randomize both its amplitude and frequency (or phase) within a manually adjustable range of 10-50% deviation. For example, the original signal would be made to randomly swing between 2Vpp and 0.2 to 1Vpp (adjustable), with a...
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