Dee:

This "show me", "show me" you are repeating causes a complete
confusion on my part.

Will you agree that a 56K phone modem, does indeed, transmit this data
rate with an audio bandwidth of ~300Hz to ~5000K, and if you do so
agree, how can you argue this cannot fit in a HF AM RF signal which
only goes 2.5K each side of center frequency??????????

Are you NOT imposing an audio frequency of AT LEAST a 5K bandwidth on
the rf carrier with normal speech? (actually, most quality
transceivers have a wider audio bandwidth than this which can be set
+/-) and if you agree you are indeed, how can you argue that 5K
bandwidth can carry a 56K data rate over a phone line--and NOT a hf rf
signal???? That looks insane to me?

The modem is NOT using the whole 5K bandwidth--necessarily, there is
compression into a narrower bandwidth which can and is generally
software controlled--if necessary (the modems software is a LOT
smarter than most give it credit for, especially in the case of the
old "onboard processor" and "hardware logic" USRobotics external
modems.

You need to explain to me why it even begins to look difficult to you
for me to be able to understand what you are asking?

As, I have to be missing something here...

You do realize that a picture good enough to run a "webcam" on the
amateur HF bands and get an acceptable image from can be done in 28K
(or less depending on the fps), and 36K is really fine at 5 fps and
good at 10 fps--you will be able to see the wart on the guys nose you
are video conferencing with at 36K!!!

You know, I have not even looked to see on the web, but aren't tons of
people doing this right now as we newsgroup?

I suppose you could actually use the rf signal as data carrier itself
and modulate it directly through on/off switching, as opposed to
modulating the rf carrier with the audio data carrier... but that
would take some heavy duty equip mods/revamps, if it didn't wipe out
the neighbors cable tv! grin

Think about this:
at 100 mhz if you can precisely control the EXACT amplitude of each
and every cycle of rf out the back end of the xmitter, you have a
virtual 100mbs data carrier... most are working here... 450 MHz?
1Ghz? 12Ghz?

.... and of course, the receiver has to be able to decipher the
amplitudes of each cycle back to a data stream for the video card...

.... this is the land where dreamers are...

John

"Dee Flint" wrote in message
...

"John Smith" wrote in message
...
Mike:

300 baud is ridiculous, in Dee's first post mentioning 300 baud I
tossed it out the window--that was fine up to about 1985, then only
the mentally challenged continued to run 300 baud modems!


Please show me and everyone else how we can run more than 300 baud
on HF without exceeding reasonable band widths. There are a whole
lot of things, not just video, that would be nice to do.

How can we do it? Bandwidth is directly related to baud rate.

Dee D. Flint, N8UZE