RadioBanter - View Single Post - Policy of resistance to HS data xmission, progress, viability...

John Smith I · March 19th 07, 07:10 PM posted to rec.radio.amateur.policy

wrote:

...
For "high speed" (really medium-low speed), the commercial
side of communications has developed the 56 KBPS modem
that works on a 3 KHz bandwidth. That is starting to bump
up against Shannon's Law, an extremely real technical
barrier. [it doesn't exceed it but it is close enough to almost
reach out and touch it...]
...
73, Len AF6AY

Len:

For all intents and purposes, 56K is HS for amateurs! I mean, sure it
is well over decade behind, but most amateurs are far behind that!

Anyway, 56K on SSB should only consume ~1.5Khz, if SSB with 3Khz
bandwidth is allowed--around ~100K can be expected. That will allow a
megabyte to be sent in ~1.5 minutes.

Now a 1.5 megabyte map can show quite a bit of detail, especially in
..JPG MONO format! That is MANY-MANY pages of the .TXT file--I mean, we
are talking a BOOK!

Yanno, in a REAL MAJOR emergency you are going to hear a LOT of people
asking, "What bandwidth rule?"

Only co-operation will be the mode of the day ...

Welcome to the new millennium, it has been a LONG time coming in these
parts ...

JS