[Elecraft] DSP - 4 questions

[Lyle Johnson]

Hello Bill!

> It is something to be sufficiently concerned enough to try and measure. I
> believe the original W9GR DSP used only an 8-bit CODEC, which caused a
> significant addition of quantization noise.

Yes, it was an 8-bit part.

> Telephone CODECs are compandored (A-law or mu-law) to an equivalent of
> 14-bits.

I think it is 12 bits, but who's counting :-)

> Perhaps 16 bits is sufficient for radio, so long as it follows
> the major selective element and the AGC.

Yes.  The AGC is fairly important here, and that the AGC "sees" the
bandwidth (or more) that the DSP sees.

> For rigs with IF DSPs providing
> all the selectivity, dynamic range is the achillies heel -- hence the 20
> to 24-bit CODECs.

Exactly.

73,

Lyle KK7P