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Posted: Mar 9th, 2008 12:54 PM |
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Jeff
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Slider2732 wrote: I have a couple of general questions relating to radio waves and more in keeping with Spiricom, as well as traditional EVP methods.You bet it is; but with digital devices, not easily done. Here's an example: The clock is a separate stage, usually fixed in frequency by a crystal made of rochelle salt, and runs continuously as long as it is energized. So we'll leave that as a given. The audio path has several stages. The first stage is the audio-to-digital converter (ADC). The input to this stage is from the microphone, or line level input(s). The analog (continuously varying voltage) signal is sampled several thousand times per second. Each sample of the incoming wave is assigned a digital number, and is stored in memory, either on media or in RAM. The next sample is stored the same way; and so on and so on... until recording is ceased. Now we have a bunch of numbers, representing voltages stored. When we play them back, those numbers are fed to the next stage: The digital-to-analog converter (DAC). This stage takes every number; converts it to a voltage potential; and feeds those voltages to an audio amplifier that either drives an output speaker; built-in to the unit; and/or to a line-level output connector that we can connect to our playback system. So a signal analyzer and oscilloscope could be placed at the input and output of each stage for analysis. Unfortunately, this would require expensive equipment that can respond to the clock frequency. Often 1GHz or more. I believe the Spirit impingement could be occuring at either section. The reason I think this, is it would make sense if the samples from the audio are being disturbed and stored in memory with such disturbance. The DAC section reads the stored data, converts back to voltage, and again, may get a disturbance, maybe even contributing to the audio distortions further. But to respond to your question, the answer is definitely yes! But I think, at this moment anyway, one would have to create other sections that are tapped from the original path, to identify and filter out those disturbances, only, and now having them isolated, can re-create the original sounds. Really, the same would apply to an analog device. At the first stage there is a pre-amplifier, which feeds to a recording amplifier (during recording). During playback, the signal is again applied to a different pre-amplifier (because of different voltage and impedance) to an output amplifier. That's it. The scope can be placed at any of these stages for analysis. But again, I refer to the recording section here, as the bias signal is of great suspect! It is RF, and can be easily modulated. I believe that in analog recording, the Spirit happens during the recording, not the playback. The bias signal cannot be heared while recording; and cannot be heard during playback. Only if it is heterodyned! Hope this all helps in one way, or another! Blessings! Jeff
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