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

John Smith wrote:
Dee:

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??????????

Of course it can.

The question is whether the RF path will have characteristics
comparable to those of the telephone line.

Are you NOT imposing an audio frequency of AT LEAST a 5K bandwidth on
the rf carrier with normal speech?

No. Typical ham transceivers only need about 2.5 kHz of audio
bandwidth.

(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?

It's a question of the characteristics of the RF path. Certainly there
are some paths that will support the amplitude- and phase- stable
requirements of the 56K modem - and some paths that won't.

On top of that is the fact that most RF paths aren't full duplex. How
fast is the 56K modem in half-duplex with transmit-receive switching?

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 are. Do you think HF offers the same transmission characteristics
as a telephone line?

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?

On telephone wires or HF radio?

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?

Think about the stability of the RF path at HF.

... 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

N2EY:

First, you can run duplex, simply use two modems and a separate
transmitter and receiver. The second modem can be a USR internal if
you don't have two serial ports for externals.

To run duplex with one modem, there is some kind of patch device they
used to keep the receiver output from getting on the mic input of the
transmitter (but the modem had simultaneous access to both)--and for
the life of me, I can't remember what it was called, first time I had
ever seen one. When I get a chance, I will ask about it. You might
know what it is/was?

Second, it works, build one--or--draw it on paper and decide it does
not work.

I am on to other things, I got tired of webcams years ago. Don't even
video chat on irc, MSN Messenger, ICQ messenger or yahoo messenger
much anymore. And that is much easier than "Mac Amateur IM."

I can tell, this argument will shortly switch to rules and
regulations, it always does, and I have no interest in having such
recited to me. Expect only my bad nature in return.

I didn't do the hardware or even know the "true nature" of the signal
which comes out of that modem and hits the phone line or a mike in. I
just toyed with the software and watched it work--it "lived" in my
garage for a year or so.

I am into my "universal translator" these days and trying to set up to
chat fluently with the russians...

I think the russian girls are kind of cute... grin

John

wrote in message
oups.com...

John Smith wrote:
Dee:

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??????????

Of course it can.

The question is whether the RF path will have characteristics
comparable to those of the telephone line.

Are you NOT imposing an audio frequency of AT LEAST a 5K bandwidth
on
the rf carrier with normal speech?

No. Typical ham transceivers only need about 2.5 kHz of audio
bandwidth.

(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?

It's a question of the characteristics of the RF path. Certainly
there
are some paths that will support the amplitude- and phase- stable
requirements of the 56K modem - and some paths that won't.

On top of that is the fact that most RF paths aren't full duplex.
How
fast is the 56K modem in half-duplex with transmit-receive
switching?

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 are. Do you think HF offers the same transmission
characteristics
as a telephone line?

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?

On telephone wires or HF radio?

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?

Think about the stability of the RF path at HF.

... 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

John Smith wrote:
N2EY:

First, you can run duplex, simply use two modems and a separate
transmitter and receiver.

Uh-huh. Got it. The reciever listens while the transmitter transmits.
On the same frequency. 'Way to go "John", slap a patent on it!

Bwwwahaha!

wrote:
John Smith wrote:
N2EY:

First, you can run duplex, simply use two modems and a
separate transmitter and receiver.

"John" just convinced me that he knows very little about
radio - HF amateur radio in particular.

Uh-huh. Got it. The reciever listens while the transmitter
transmits.
On the same frequency. 'Way to go "John", slap a patent on it!

Bwwwahaha!

Did you notice there was no mention of antennas?

Poor soul prolly doesn't know what "QSK" means, either.

73 de Jim, N2EY

wrote:
wrote:
John Smith wrote:
N2EY:

First, you can run duplex, simply use two modems and a
separate transmitter and receiver.

"John" just convinced me that he knows very little about
radio - HF amateur radio in particular.

Uh-huh. Got it. The reciever listens while the transmitter
transmits.
On the same frequency. 'Way to go "John", slap a patent on it!

Bwwwahaha!

Did you notice there was no mention of antennas?

Yeah, I realized immediately after I posted that I'd missed that "litle
detail" myself. Nutz, I leaped too fast again. But then again maybe his
RX has a built-in sprinkler system . . ? We dunno . .

Poor soul prolly doesn't know what "QSK" means, either.

Why would he? Ya don't find a a helluva lot of QSK ops on 11M.


73 de Jim, N2EY

w3rv

wrote:
wrote:

John Smith wrote:

N2EY:

First, you can run duplex, simply use two modems and a
separate transmitter and receiver.


"John" just convinced me that he knows very little about
radio - HF amateur radio in particular.

Took long enough, Jim! ;^)

Uh-huh. Got it. The reciever listens while the transmitter
transmits.
On the same frequency. 'Way to go "John", slap a patent on it!

Bwwwahaha!


Did you notice there was no mention of antennas?

Isotrons. It would at least look kinda kewl. 8^)

Poor soul prolly doesn't know what "QSK" means, either.

Does it matter?.......

- Mike KB3EIA -

From: on Tues 5 Jul 2005 16:41


John Smith wrote:
N2EY:

First, you can run duplex, simply use two modems and a separate
transmitter and receiver.

Uh-huh. Got it. The reciever listens while the transmitter transmits.
On the same frequency. 'Way to go "John", slap a patent on it!

Did John say "on the same frequency?" I don't think so.

FULL duplex IS possible using SEPARATE frequencies for
transmit and receive. [note spelling of "receive"]

Did that over 50 years ago on 9 terminals at 1.8 GHz.
Full duplex. Twenty-four voice channels each terminal.
No problem.

Bwwwahaha!

Tsk. Started "happy hour" early, did you? :-)

bit bit

wrote:
From: on Tues 5 Jul 2005 16:41

John Smith wrote:
N2EY:

First, you can run duplex, simply use two modems and a separate
transmitter and receiver.

Uh-huh. Got it. The reciever listens while the transmitter transmits.
On the same frequency. 'Way to go "John", slap a patent on it!

Did John say "on the same frequency?" I don't think so.

He didn't say *not* on the same frequency either Sweetums. Now what?


FULL duplex IS possible using SEPARATE frequencies for
transmit and receive.

No kidding Sweetums I've done it several times myself. With my own
equipment operated under my own operators and station license.

But in your case of course . . sigh

From: on Wed 6 Jul 2005 15:54

wrote:
From: on Tues 5 Jul 2005 16:41
John Smith wrote:
N2EY:

First, you can run duplex, simply use two modems and a separate
transmitter and receiver.

Uh-huh. Got it. The reciever listens while the transmitter transmits.
On the same frequency. 'Way to go "John", slap a patent on it!

Did John say "on the same frequency?" I don't think so.

He didn't say *not* on the same frequency either Sweetums. Now what?

Two questions:

1. What ELSE did John "*not* say?"

2. What are you going to say he "really said?" :-)

This is all very clever of you, but it really boils down to
YOU saying a lot of snit (that another didn't say) and then
trying to tap-dance around admitting you fudged things up.

Next time just accept being caught and hang up.

Do NOT try to MAKE UP STORIES to try and snow-job everybody.
It doesn't work and it annoys the other pigs.


FULL duplex IS possible using SEPARATE frequencies for
transmit and receive.

No kidding Sweetums I've done it several times myself. With my own
equipment operated under my own operators and station license.

Mostly I think you "did it" with only your own computer and
more literary license than you ever earned. :-)

But, that's just my opinion...and with some considerable
thinking about HF operations that hardly EVER go FULL duplex,
senior. For one thing, the rather large near field at HF
wavelengths mean you NEED considerable separation of antennas
or the most bodaciously-many-section-dual-filter to keep the
unwanted frequencies (transmitter leaking into receiver) OUT.
That attenuation has to be VERY large in order to keep the
receiver input from overloading.

Now, WHY would you want to go FULL duplex "operating under any
license?" for personal use? You would need someone at the other
end of the circuit doing the same thing...and that is an almost-
extreme rarity.

Telephone Cell sites operate 24/7 at FULL duplex. They HAVE to
and the equipment is designed to do that...such as separate
transmitting and receiving bands with plenty of diplexing filter
connecting the transmitter(s) and receiver(s).

The General Electric microwave terminals I've described used a
(approximately) 5-foot long dual waveguide bandpass filter to
keep separate transmit and receive frequencies from interfering
with one another. The pulse-position-modulation pulse trains
were not synchronous with one another, thus aiding in isolation.
The peak power output of the transmitter was only 12 Watts (at
base of antenna tower) yet the receiver was about as sensitive
as one could get (using radar receiver techniques) of the 1950s.

If you are going to mumble about "your own moonbounce" (what is
mistakenly called "EME" by hams), then you need not worry about
mutual interference. A return signal won't return from the moon
for about 2.5 seconds, long enough for you to manually swtich
coax or waveguide between transmit and receive (as one of the
early ham moonbouncers did and pictured in CQ long ago).

Or, you could go into broadband BS about using morse and auto-
switchover Tx/Rx by fancy diode T/R switching...so much so that
you could "read the other station between dots and dashes" like
your buddie Jimmie once said in here. :-)

But in your case of course . . sigh

In "my case" you are resentful/insulted/irritated because another
had LONG AGO experience in something YOU DID NOT. shrug I've
come to expect that in here from the self-propelled wunderkinder
of the PCTA extra crowd. It's practically a given. :-)