John Rippey wrote:
E. Alternatively, it's possible to modify a TS-870S by shoe-horning
INRAD filters in place of the stock 2d and 3d IF filters, and this
produces a radio with pretty good dynamic range.
Excuse me John, but this sounds wrong to me. The dynamic range is
limited by the analog to digital converter. Narrowing the bandpass that
the ADC sees does not increase it's dynamic range, although it may
decrease the need for a large a dynamic range. So then what was not good
enough may then become pretty good. Still the dynamic range is the same.
If the little signal you are trying to copy and the big signal you want
to reject are both inside the (narrower than stock) roofing filter
bandwidth, your ability to separate them is still limited by the dynamic
range of the ADC. Since with a narrower roofing filter you have less
total power to digitize, you can get away with a smaller dynamic range a
lot of the time.
DE N6KB
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