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Old March 30th 17, 07:22 PM posted to rec.radio.amateur.digital.misc
Bill Gunshannon[_7_] Bill Gunshannon[_7_] is offline
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First recorded activity by RadioBanter: Nov 2016
Posts: 10
Default 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