A Modest Proposal to Save Five-Level Code
 

On 30/03/2017 17:31, Rob wrote:
Gareth's Downstairs Computer wrote:
On 30/03/2017 15:01, Rob wrote:

5-level codes are typically used with FSK or AFSK modulation so there
is a lot of efficiency to be gained by implementing a more efficient
modulation method. When doing that, you can do some compression as well.

GMSK?

No, not by far. Typical RTTY is sent with 170Hz shift FSK at a rate
of 50 baud, so well above GMSK.


I meant _TRY_ GMSK?

A Modest Proposal to Save Five-Level Code
 

On 3/30/2017 12:31 PM, Rob wrote:
Gareth's Downstairs Computer wrote:
On 30/03/2017 15:01, Rob wrote:

5-level codes are typically used with FSK or AFSK modulation so there
is a lot of efficiency to be gained by implementing a more efficient
modulation method. When doing that, you can do some compression as well.

GMSK?

No, not by far. Typical RTTY is sent with 170Hz shift FSK at a rate
of 50 baud, so well above GMSK.


You could always go to 85hz like the government did. Should cut the
bandwidth in half. :-)

bill