Mike Coslo wrote:
Dave Heil wrote:
wrote:
How we be gonna scale those pictures and live video to fit into 2.5 KHz?
Two steps:
1) Convert the pictures and video into highly-compressed digital
formats for transmission.
2) Use different modes/modulations/protocols
Shannon's Theorem tells us that we can get very high data rates through
very narrow bandwidths *if* we have adequate signal-to-noise ratio.
Note that "noise" takes many forms, not just the thermal noise we're
used to.
For example, PSK has an advantage over OOK when dealing with thermal
noise. But when dealing with other types of noise, OOK can have an
advantage. It all depends on the transmission medium. What works on a
telephone line may not work on an HF path of the same apparent
bandwidth.
I thought that we were going to be able to send live video
and digital images on HF?
You can do that now - just need enough S/N.
Simply by hooking our computers to our rigs via the
proper interfaces.
And software.
Now it seems that the *idea* is that we are going to use
DRM, and we're
going to need to get more spectrum in which to use.
There are all sorts of solutions. But there's a world of
difference between people talking theory and actual
application.
Most of all, some folks confuse the journey and the destination.
Does complex and newer equal better?
Sometimes. Not always.
Is analog simpler than digital?
Sometimes!
Does having a computer that attaches to the Internet
make a person a digital expert?
Some folks think so! I don't. And besides - "digital expert" doesn't
mean someone knows much about radio.
I ask for enlightenment, I get invective.
Are you surprised?
Appears to be what there is to offer.
Now consider how effective such a person would
be trying to sell amateur radio - with or
without a code test.
73 de Jim, N2EY