Author Topic: Online SDRs: Is it possible to find the Center Frequency?  (Read 234 times)

K5KNT

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A few questions regarding online SDRs and the Center Frequency:

Is knowing the center frequency necessary or important?

If so, is it possible to determine the center frequency?

If yes, how would this be accomplished?

Thanks,

K5KNT
K5KNT
Grand Forks, ND, USA

KaySeeks

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Re: Online SDRs: Is it possible to find the Center Frequency?
« Reply #1 on: April 07, 2018, 0041 UTC »
The center frequency of the signal you are receiving?
Just somebody with a radio and a pair of headphones...

K5KNT

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Re: Online SDRs: Is it possible to find the Center Frequency?
« Reply #2 on: April 07, 2018, 0108 UTC »
I"m not sure. In Appendix B of the Harvester User manual it says:
Quote
Determine the centre frequency of your receiver. This is particularly important
when receiving OOK or FSK signals and enabled [sic] you to accurately establish the
correct transmitter frequency.

I'm not actually using this software, but I found the User Manual interesting.
K5KNT
Grand Forks, ND, USA

Josh

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Re: Online SDRs: Is it possible to find the Center Frequency?
« Reply #3 on: April 07, 2018, 1745 UTC »
In that case they refer to the cf, or center of intelligence of the given signal. If the mark of a 1000hz shift fsk sig is at 22.490 and the space is at 22.491. the cf is 22.490.5.
For a cw sig, if using a sdr, just look at the carrier and note the freq at the peak it occupies. For a non sdr rig you either add or subtract the beat note from the dial freq to get the cf, depending on if your bfo is above or below the cw.

K5KNT

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Re: Online SDRs: Is it possible to find the Center Frequency?
« Reply #4 on: April 07, 2018, 1833 UTC »
Thank you.  :)
K5KNT
Grand Forks, ND, USA