HFU HF Underground
Loggings => North American Shortwave Pirate => Topic started by: ChrisSmolinski on June 02, 2018, 1839 UTC
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Presumed Relay Station
1838 Red Hot Chili Peppers "Dark Necessities", SIO 222 to 333.
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1853 UTC Mostly a weak carrier with some threshold audio and brief fade ups.
1855 UTC "My Doorbell"-White Stripes
1900 UTC OFF? Carrier gone also
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hi Chris & Skip.
i was testing out the blackman 7 bandwidth filter i installed which is set to 20Khz Bandwidth (10Khz each side band) at a high order of magnitude.
the blackman filter provides a sharp drop off at 10Khz versus ST's built in filter which has a rolling dB drop off staring from 9Khz to 10Khz, i prefer the blackman filter as its flat across the board.
though i wasnt too thrilled about the minor aliasing at the upper audio frequency spectrum during a sweep test (with and without the blackman filter), it wont be detrimental to music and speech, its a minor issue at this point.
during the test, i sent 20Hz and 40Hz sine wave tones and observed the results at SDR demod and was very satisfied with the ending results.
you certainly would have seen your sub-woofer moving at 20Hz provided your receiver is capable of receiving the low end of the audio spectrum :D
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have you tried a hanning filter?
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have you tried a hanning filter?
yes. the han filter is good but the blackman is better for what im doing but each filter works differently for each application.
after last nights broadcast, i decided not to use the blackman filter and instead opted to use the built in filter in ST because the sound was lacking dynamics.