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<font size="+1"><font face="Comic Sans MS">Ah of course, slap my
head, should have seen that! It's data so nothing is the same
as something in that you get a message either way. <br>
So the reason you need such a fast computer is to process the
data in near real time. <br>
Could even the 100 MHz USB3 device be streamed to storage and
then the data crunched later? <br>
I guess that's the only way with just a PC to see what sneaky
little signals are hiding in the grass. <br>
<br>
Terry N4TLF wrote on 5/30/2017 1:07 PM:
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<div>Hey Alex,</div>
<div>If you mean that you are saving to disk the raw ADC
samples, then the files will be the same size,
regardless of how many or how few signals are there. No
signals just means a lower value will be recorded to the
disk. But probably very few 0x0000 values. More
stations just means more recorded samples with higher
values. The file size will depend only on number of
bits per sample, the sample rate, and the length that
samples are recorded.</div>
<div> </div>
<div>Same with noise versus no noise. This all assumes NO
fancy compression techniques are used on the file. No
noise means sample values will be closer to zero, noise
means more randomness of, and higher values in the
samples.</div>
<div>73, Terry, N4TLF</div>
<div> </div>
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<div style="font-color: black"><b>From:</b> <a
title="beatnic@comcast.net">Alex Fraser</a> </div>
<div><b>Sent:</b> Tuesday, May 30, 2017 12:54 PM</div>
<div><b>To:</b> <a title="tacos@amrad.org">AMRAD
Tacos</a> </div>
<div><b>Subject:</b> Re: Three new SDRs in the shack</div>
</div>
</div>
<div> </div>
</div>
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size="+1" face="Comic Sans MS">I was thinking this
morn, probably the coffee. <br>
So if you record to disk I would think that if you
captured a portion of the spectrum with many stations
that the file size would be greater than a less busy
part of the spectrum. Is that true? Then I thought
if you recorded a part of the spectrum with noise at a
certain level and then recorded another part of the
spectrum with a higher noise level, then would the 2
files sizes be the same or different? I'm ignoring OS
overhead.<br>
I'm sure there is a mathematical explanation for this
and if need be I WILL drink more coffee...<br>
<br>
Terry Fox wrote on 5/29/2017 8:46 PM:
<blockquote type="cite">I have recently purchased
three new SDRs for testing and playing with. Up
front: I have NO RELATIONSHIP with any of these
companies, other than being a customer, who paid
full-price for everything. <br>
<br>
1/2: BooyaSDR <br>
The first two are BooyaSDR units. These are
different than almost all other SDRs available to RF
enthusiasts at the moment, in that they sample the
RF input directly, then send ALL those samples to
the host computer. No FPGA or other device to
reduce the amount of samples. The host computer
then does all the computations to show the FULL
bandwidth of their respective input. The software
shows this spectrum display in a series of
waterfalls stacked on top of each other. I
purchased one of the 100MHz full SDR & antenna,
and then a 16MHz digitizer set, less antenna. I
also have a 64MHz oscillator that I can put in place
of the socketed 100MHz oscillator, so I can test the
boards at that lower rate. <br>
<br>
</blockquote>
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<pre class="moz-signature" cols="72"><font size="+1" face="Comic Sans MS">--
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~~~******************* Alex Fraser *******************~~~
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<br>
</font></font><br>
<pre class="moz-signature" cols="72">--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
No electrons were harmed in the creation of this message
--------------------------------------------------------
~~~******************* Alex Fraser *******************~~~
--------------------------------------------------------
[[[[[[~~^^^#___=>>>```/\/\**O**/\/\```<<<=___#^^^~~]]]]]]
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