WWV Calibration SmartSDR Version 1.5

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  • Question
  • Updated 3 years ago
  • (Edited)

Can other than WWV 15.000mhz be used when the band does not permit?

Like 10.000 or 5.000 MHz ?

And stronger signal  the better?


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AA0KM

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Posted 3 years ago

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Simon Lewis

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yup just enter the freq on the radio setup tab and away it goes!
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Tim - W4TME, Customer Experience Manager

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Yes, any realitively strong WWV or CHU over the air frequency standard signal or any other known frequency standard. However 15 MHz is close to the center of the HF bands so it is why it is the default.
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AA0KM

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Thanks. I kind of figured it was ok but to be sure thought I would ask.

73


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Bill W2PKY

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Recalibrated and checked against FLDIGI: 0-1 cycle, most of time less than .05 cycles. Amazing.
(Edited)
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Bob Brown - N8OB

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I ran the recalibration and it showed an offset of -856 ppm or 20 hz low on my setup.  I manually reset to +430 ppb and reading was at 0.1 hz.  Does using SAM make a difference?  I also used FLDIGI the same way I use it for FMT.  My readings on FMT have usually been less than 0.5 hz off
+
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Simon Lewis

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does the -1349 ppb mean the amount of offset applied to get it on 10 MHz or is it the error existing between WWV and the radio??
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Tim - W4TME, Customer Experience Manager

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Simon - yes to the first part - it is the amount of offset that was applied to get the radio on frequency.  Once you run the calibration, the radio is on frequency.

I would not concern yourself with the amount of offset or the magnitude.  It is there for informational purposes only and for you to tweak it if you have a better frequency standard than WWV, which suffers from Doppler shift and selective fading. 
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Tim - W4TME, Customer Experience Manager

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DK1KQ - if your offset is -1349 ppb, then your radio is off by 13.49 Hz @ 10 MHz when the offset value is zero (0).  Since you have an offset applied, your radio is on frequency.
(Edited)
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Bob Brown - N8OB

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I'm starting to believe that if the radio is actually "on frequency" after running calibration, then WWV must be the problem.  If what you are saying is true, then why doesn't the reading agree with WWV, at least more closely?
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Tim - W4TME, Customer Experience Manager

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Bob - I do not have enough information to know how you have determined you are off frequency so I can't answer your question.
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Bob Brown - N8OB

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I use Spectrum Lab and/or FLDIGI, zero in on the 1khz tone offset in USB. This is the procedure I have used for a few years in running the Frequency Measuring Test.  Using this method usually puts me within less than 1 hz from the known transmit frequency. This method on the Flex, gives me a reading about 10 to 20 hz low in frequency. I can adjust the ppb setting to correct it but that reading becomes about +450 ppb for my readings to agree with WWV.