RSP1A/RSP1B DAB Filter

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iceman977th

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Does anyone have a chart for the DAB filter for the RSP1A and RSP1B? It's listed as 160-235MHz on SDRTrunk, the only PDF I find says 165-235MHz.. I'm setting up a RSP1A to receive rail and trying to figure out if I should leave it enabled or not, since rail is 160-162MHz. I'm right next to a NOAA Wx radio transmitter, and it's signal is significantly reduced when I enable the filter.
 
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Ubbe

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Specification says more than 30dB attenuation at 165MHz and if you make a filter to notch such a wide range as 165-235MHz it will not be super sharp at its edges. You will lose a lot of signal at 160MHz. If you look at the FM broadcast filter comparison that has about the same bandwidth in percentage for its notch as that DAB filter, you'll see that it can, at 10% down in frequency from a -30dB notch, still be a 6-10dB notch present. For double the frequency it will probably be that 6-10dB loss 10MHz down.

If you look at a RPS1a board layout you'll see that it uses standard passive component filters using coils and capacitors and no sharp SAW filters or equal expensive high quality components anywhere in its circuits.

/Ubbe
 
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