Re: [Flexradio] Spur in PSK31 output even with no rf out into Dummyload.

[Bob McGwier]

I was going to say this perfectly demonstrates both the great power 
(sensitivity) of the panadapter and our greatest curse at the same time. 
 I was going to give my usual long winded commentary but I must admit 
that your 3 letter comment is right to the point.


There are design compromises in our resampler (which will be eliminated 
in an all new version of things later by using the arbitrary phase 
resampler which will have 120 dB noise floor and cost FEWER ticks by 
lots than the current one).  But VAC itself has a resampler or uses the 
WinBLOWS resampler (horrible) depending on the interface, driver, etc.


YO PEOPLE.  When you have 140 dB of dynamic range displayed in front of 
you as in our panadapter with standard settings,  get an idea that is 
FOURTEEN orders of magnitude in power, seven in voltage.  10^14 is a 
very large number and is huge in signal processing even if it is about 
the right amount when discussing next year's US government deficit spending.

;-)


73's
Bob
N4HY

On 2/3/2010 6:37 AM, Lee A Crocker wrote:
Apparently little known fact:

If you are 80dB down from a 27 watt signal you are transmitting  0.0000027 watts

BFD

73  W9OY





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