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  • Updated 4 years ago
I read a post from Steve at Flex describing how with a narrower Panadapter bandwidth the frequency bins are smaller and how smaller bins reduce the S/N level, or something to that effect. As I understand things, the sampling rate determines the bin size. Since the 6500 and 6700 have a higher sampling rate, does that mean that those receivers are better than the 6300? Not that there is any problem with the 6300, I would expect a $7k radio to be better than a $2.5k one.
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Mark Erbaugh

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Posted 4 years ago

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Steve - N5AC, VP Engineering / CTO

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Official Response
Zooming in and out on the panadapter changes the bin size -- the narrower the display, the smaller the bin size and the higher the SNR because the noise level is lower.  This effect is true of any receiver, but in the FLEX-6000 the changes to the panadapter do not affect the slice receivers.  The slice receiver is "a single bin" or receiver itself.  That bin is 24kHz wide, but you can reduce the total noise in the bin with filtering.  If the signal you are listening to is 300Hz wide and you reduce the filter from 3kHz to 300Hz, you reduce the noise level by 10dB and increase the SNR by 10dB.  BUT your ears do this anyway to some extent.  Many people prefer to let their ears do this if there are not offending signals nearby.  Your mileage may vary.

The sampling rate provides additional benefits through oversampling -- both the 6500 and 6700 are 2x oversampled from the 6300.  The 6700 also has two additional zoom levels that the other radios do not have, which means its panadapter can look an additional 6dB into the noise.  You get nothing for "free" so the cost of this in the 6700 is the speed of the panadapter refresh in this mode.  But if you are hunting for a signal in that noise, it's a good tradeoff.