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  #501   Report Post  
Old February 8th 04, 09:54 PM
JJ
 
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Len Over 21 wrote:



You don't even have artificial intelligence.


No I don't, that is what you have only someone forgot to program it.

You aren't impressing anyone.


Of all the people in the world I couldn't care less if I impress, you're it.


  #502   Report Post  
Old February 8th 04, 10:49 PM
garigue
 
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Remember, morse code gets through when everything else will.

LHA / WMD


Good one Len ..... have to remember it ....

God Bless KI3R Tom Popovic Belle Vernon Pa.




  #504   Report Post  
Old February 9th 04, 11:25 PM
N2EY
 
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Default

Leo wrote in message . ..

I understand that Morse is good for getting through poor conditions
better than voice.


Much better than any form of analog voice.

Makes sense, it is narrowband and binary (well,
tri-state if you count the spaces...) encoded.


Exactly.

From the experimenting
(read: fooling around) that I have been doing over the past couple of
months, I have been repeatedly amazed with the ability of BPSK-31 to
get clean copy through pretty bad conditions. Even DX signals that
appear as weak vestiges on the waterfall display can be easily decoded
with near 100% accuracy, using just a PC sound card as an interface.


The soundcard is only part of the system. The decoder is quite smart,
in that
it stores and examines the received data and does a "best fit"
decoder. You can read all about it at several websites.

But it's important to realize what constitutes "poor conditions".
Against purely amplitude noise it's quite robust. But against phase
noise of various
types it is not robust at all. All depends on the situation.

Frequency stability of my old Heath TX is a problem, but I'm working
on it.....


What rig is it?

Now there's something that will get through when nothing else will.


Not really. You will find times when the PSK-31 signal is clearly
audible in the speaker, well above the background amplitude noise, but
the decoder cannot make sense of it because the phase distortion is
too bad.

And, it types itself out, too. (that's a real boon for the perennially
lazy - like me)


It was meant as a replacement for conventional RTTY - as a "keyboard
to keyboard" mode. For example, the speed was chosen to be about what
*average* conversational keyboarding hams use.

btw, the code used in PSK-31 uses shorter symbols for the most common
characters and longer ones for the least common. Just like Morse code,
which is where the designers got the idea.

I believe that BPSK-31 was created within the amateur community -


Yup - G3PLX, and a number of folks who helped him by testing it out on
the air and others who have developed software packages. A local ham
of my acquaintance (one of those longtime 20 wpm 1x2 Extras with
multiple EE degrees - we share two alma maters, btw) was one of the
team who helped test it out.

PSK-31 is another great tool in the toolbox, but not a replacement for
good old Morse Code.

73 de Jim, N2EY
  #505   Report Post  
Old February 10th 04, 01:03 AM
Leo
 
Posts: n/a
Default

On 9 Feb 2004 15:25:04 -0800, (N2EY) wrote:

Leo wrote in message . ..

I understand that Morse is good for getting through poor conditions
better than voice.


Much better than any form of analog voice.

Makes sense, it is narrowband and binary (well,
tri-state if you count the spaces...) encoded.


Exactly.

From the experimenting
(read: fooling around) that I have been doing over the past couple of
months, I have been repeatedly amazed with the ability of BPSK-31 to
get clean copy through pretty bad conditions. Even DX signals that
appear as weak vestiges on the waterfall display can be easily decoded
with near 100% accuracy, using just a PC sound card as an interface.


The soundcard is only part of the system. The decoder is quite smart,
in that
it stores and examines the received data and does a "best fit"
decoder. You can read all about it at several websites.


Good point - I've compared it to RTTY from the decoding standpoint -
RTTY seems to be much more prone to losing characters or dropping out
entirely when the signal is weak or noise is high.


But it's important to realize what constitutes "poor conditions".
Against purely amplitude noise it's quite robust. But against phase
noise of various
types it is not robust at all. All depends on the situation.



Frequency stability of my old Heath TX is a problem, but I'm working
on it.....


What rig is it?


Heath SB-400. The Pride of 1964

With a narrowband signal like this, it doesn't take much drift! I'm
seeing a frequency decrease of up to 15 Hz, beginning a few seconds
after keying. B+ to the VFO appears to be well regulated - maybe not
tight enough though. Might have to replace the 0A2 with a few zeners
- haven't tried that yet....


Now there's something that will get through when nothing else will.


Not really. You will find times when the PSK-31 signal is clearly
audible in the speaker, well above the background amplitude noise, but
the decoder cannot make sense of it because the phase distortion is
too bad.


Haven't experienced that yet - at least when I see that, I'll know
what is causing it!


And, it types itself out, too. (that's a real boon for the perennially
lazy - like me)


It was meant as a replacement for conventional RTTY - as a "keyboard
to keyboard" mode. For example, the speed was chosen to be about what
*average* conversational keyboarding hams use.

btw, the code used in PSK-31 uses shorter symbols for the most common
characters and longer ones for the least common. Just like Morse code,
which is where the designers got the idea.


Didn't know that - great idea, though!


I believe that BPSK-31 was created within the amateur community -


Yup - G3PLX, and a number of folks who helped him by testing it out on
the air and others who have developed software packages. A local ham
of my acquaintance (one of those longtime 20 wpm 1x2 Extras with
multiple EE degrees - we share two alma maters, btw) was one of the
team who helped test it out.

PSK-31 is another great tool in the toolbox, but not a replacement for
good old Morse Code.


Haven't formulated an opinion on that one yet - stay tuned!


73 de Jim, N2EY


73, Leo



  #507   Report Post  
Old February 10th 04, 04:10 AM
Dee D. Flint
 
Posts: n/a
Default


"N2EY" wrote in message
m...
Leo wrote in message

. ..

I understand that Morse is good for getting through poor conditions
better than voice.


Much better than any form of analog voice.

Makes sense, it is narrowband and binary (well,
tri-state if you count the spaces...) encoded.


Exactly.

From the experimenting
(read: fooling around) that I have been doing over the past couple of
months, I have been repeatedly amazed with the ability of BPSK-31 to
get clean copy through pretty bad conditions. Even DX signals that
appear as weak vestiges on the waterfall display can be easily decoded
with near 100% accuracy, using just a PC sound card as an interface.


The soundcard is only part of the system. The decoder is quite smart,
in that
it stores and examines the received data and does a "best fit"
decoder. You can read all about it at several websites.

But it's important to realize what constitutes "poor conditions".
Against purely amplitude noise it's quite robust. But against phase
noise of various
types it is not robust at all. All depends on the situation.

Frequency stability of my old Heath TX is a problem, but I'm working
on it.....


What rig is it?

Now there's something that will get through when nothing else will.


Not really. You will find times when the PSK-31 signal is clearly
audible in the speaker, well above the background amplitude noise, but
the decoder cannot make sense of it because the phase distortion is
too bad.

And, it types itself out, too. (that's a real boon for the perennially
lazy - like me)


It was meant as a replacement for conventional RTTY - as a "keyboard
to keyboard" mode. For example, the speed was chosen to be about what
*average* conversational keyboarding hams use.

btw, the code used in PSK-31 uses shorter symbols for the most common
characters and longer ones for the least common. Just like Morse code,
which is where the designers got the idea.

I believe that BPSK-31 was created within the amateur community -


Yup - G3PLX, and a number of folks who helped him by testing it out on
the air and others who have developed software packages. A local ham
of my acquaintance (one of those longtime 20 wpm 1x2 Extras with
multiple EE degrees - we share two alma maters, btw) was one of the
team who helped test it out.

PSK-31 is another great tool in the toolbox, but not a replacement for
good old Morse Code.

73 de Jim, N2EY


As I tell my students EVERY mode has its advantages and disadvantages. Each
has its place in the scheme of things. If they have not tried out the modes
within their financial reach, they have shortchanged their "toolbox."

Dee D. Flint, N8UZE

  #508   Report Post  
Old February 10th 04, 04:13 AM
Dee D. Flint
 
Posts: n/a
Default


"Leo" wrote in message
...
On 9 Feb 2004 15:25:04 -0800, (N2EY) wrote:

Leo wrote in message

. ..

I understand that Morse is good for getting through poor conditions
better than voice.


Much better than any form of analog voice.

Makes sense, it is narrowband and binary (well,
tri-state if you count the spaces...) encoded.


Exactly.

From the experimenting
(read: fooling around) that I have been doing over the past couple of
months, I have been repeatedly amazed with the ability of BPSK-31 to
get clean copy through pretty bad conditions. Even DX signals that
appear as weak vestiges on the waterfall display can be easily decoded
with near 100% accuracy, using just a PC sound card as an interface.


The soundcard is only part of the system. The decoder is quite smart,
in that
it stores and examines the received data and does a "best fit"
decoder. You can read all about it at several websites.


Good point - I've compared it to RTTY from the decoding standpoint -
RTTY seems to be much more prone to losing characters or dropping out
entirely when the signal is weak or noise is high.


But it's important to realize what constitutes "poor conditions".
Against purely amplitude noise it's quite robust. But against phase
noise of various
types it is not robust at all. All depends on the situation.



Frequency stability of my old Heath TX is a problem, but I'm working
on it.....


What rig is it?


Heath SB-400. The Pride of 1964

With a narrowband signal like this, it doesn't take much drift! I'm
seeing a frequency decrease of up to 15 Hz, beginning a few seconds
after keying. B+ to the VFO appears to be well regulated - maybe not
tight enough though. Might have to replace the 0A2 with a few zeners
- haven't tried that yet....


Now there's something that will get through when nothing else will.


Not really. You will find times when the PSK-31 signal is clearly
audible in the speaker, well above the background amplitude noise, but
the decoder cannot make sense of it because the phase distortion is
too bad.


Haven't experienced that yet - at least when I see that, I'll know
what is causing it!


And, it types itself out, too. (that's a real boon for the perennially
lazy - like me)


It was meant as a replacement for conventional RTTY - as a "keyboard
to keyboard" mode. For example, the speed was chosen to be about what
*average* conversational keyboarding hams use.

btw, the code used in PSK-31 uses shorter symbols for the most common
characters and longer ones for the least common. Just like Morse code,
which is where the designers got the idea.


Didn't know that - great idea, though!


I believe that BPSK-31 was created within the amateur community -


Yup - G3PLX, and a number of folks who helped him by testing it out on
the air and others who have developed software packages. A local ham
of my acquaintance (one of those longtime 20 wpm 1x2 Extras with
multiple EE degrees - we share two alma maters, btw) was one of the
team who helped test it out.

PSK-31 is another great tool in the toolbox, but not a replacement for
good old Morse Code.


Haven't formulated an opinion on that one yet - stay tuned!


73 de Jim, N2EY


73, Leo


Just to add to information, I heard a couple of hams talking shortly after
the major solar flares of this past fall were finally over. They had
commented on the fact that the distortion on PSK31 was so bad that they had
had to switch to Morse.

Dee D. Flint, N8UZE

  #509   Report Post  
Old February 10th 04, 04:55 AM
Len Over 21
 
Posts: n/a
Default

In article [email protected]_s04, "garigue"
writes:

Remember, morse code gets through when everything else will.

LHA / WMD


Good one Len ..... have to remember it ....


Credit Brian Burke with the phrase. He had that truism right,
worthy of repeating. :-)

LHA / WMD


  #510   Report Post  
Old February 10th 04, 04:55 AM
Len Over 21
 
Posts: n/a
Default

In article , Leo
writes:

Remember, morse code gets through when everything else will.


....That line still makes me laugh every time I read it!


It is absolutely, positively, 100% true. Brian Burke's phrase should
go into the textbooks. :-)

I understand that Morse is good for getting through poor conditions
better than voice. Makes sense, it is narrowband and binary (well,
tri-state if you count the spaces...) encoded. From the experimenting
(read: fooling around) that I have been doing over the past couple of
months, I have been repeatedly amazed with the ability of BPSK-31 to
get clean copy through pretty bad conditions. Even DX signals that
appear as weak vestiges on the waterfall display can be easily decoded
with near 100% accuracy, using just a PC sound card as an interface.
Frequency stability of my old Heath TX is a problem, but I'm working
on it.....

Now there's something that will get through when nothing else will.
And, it types itself out, too. (that's a real boon for the perennially
lazy - like me)

I believe that BPSK-31 was created within the amateur community -
there must have been similar narrowband technologies used by the
military which predated it - any idea what they were?


PSK31 was designed/innovated by Peter Martinez, G3PLX, in the
UK, then air-tested by several over much of Yurp. Years ago.

There's a whole heaping lot of techniques/systems used by the
militaries (of the world, actually) on sending data/teleprinter over
both wire and radio circuits. Too many to recount in here. Few of
the militaries or the governments or the commercial carriers bother
with narrowband-specific communication circuits since they have
needs to send much data quickly. The advance in Information
Theory and Coding (generic other than morse code or character
codes) have applied themselves to other things besides comm
applications: Single-error correction, double-error detection for
computer memory applications to real-time analysis of seismic
effects on building structures. Real-time Fourier Analysis has
been at the heart of that and includes mundane things like the
little audio bargraph displays on home music systems (usually
combined with "equalizer" settings of same).

The "MIT Redbook" by Peterson and Weldon is a thick text
chock full of all sorts of data coding schemes, error correction of
same, plus ways other than Forward Error Correction to send data
best without extra bits (something alluded to in Shannon's seminal
1948 paper that became familiarly known as "Shannon's Law").

The VLF Alert messages in the USN submarine fleet is not a
subject of discussion. Those are digital, encrypted, and have some
other features to work through all kinds of RF interference. The
militaries/governments/commercial carriers generally confine them-
selves to rather standard medium- to high-throughput systems for
radio circuits without going into complicated schemes. The various
"TOR" modes are very close to those. Add to that the ALE or
Automatic Link Establishment interrogation-response on auto-
measurement of signal quality and that is the broad picture of what
goes on by non-amateur communications HF to VHF. Note: Some
of the details of everyday encryption are in the grey area of talk and
I won't go into that due to prohibitions of U.S. law. If any such appear
on the Internet, it has been cleared for public viewing, not classified.

A wide example of medium- to high-rate data communications allied
to the basics of PSK31 is the common data modem used with
personal computers. It can, with a good POTS line (Plain Old Telephone
System), send 56K data rate material over a 3 KHz bandwidth. There
are, literally, millions of those modems in existance; 152 million
personal computers were sold worldwide in 2003 alone according to a
story in LA Times Business section for 9 Feb 04.

The standard data modem with PCs uses a combination of amplitude
and phase modulation of a carrier tone plus some rudimentary digital
state re-arrangments to get a rate increase far above conventional
single-mode modulations yet it does not violate Shannon's Law. Many
who can only grasp the single-mode concepts keep trying to say "it
isn't possible!" yet the possible is happening 24/7 worldwide by the
millions. The generality of such dramatic rate versus bandwidth can
be applied anywhere. PSK31 was one of those, cleverly arranged
by Martinez to fit into a bandwidth equal to a morse code spectral
space and perform just a bit better at an average throughouput of
about 30 WPM. The PSK31 system is a complex one yet quite
easy to implement with the aid of a (now) common personal
computer. The PC isn't absolutely necessary since a dedicated
terminal or radio modem can be built in a smaller package...but
still needs a keyboard, display-printer to complete the data terminal.

What is astounding, in a world of technological plenty, that there are
so many radio-backwoodsmen demanding that all revert to village
blacksmith or horse & buggy driver or other primitiveness in a hobby
activity to fulfill some mythical "requirement of knowing 'basics'" in
order to be "as good as them!" Their "knowledge" of data comms is
relegated to the memorizing-of-manufacturer's-advertisements-
descriptions for "technical familiarity"...if a description says that a
system operates at a low data rate, they cannot envision the possible
scaling to a high data rate...and vice-versa, very high data rate scaled
down to slower speed and narrower bandwidth.

The first commercial telegraph circuit opened in 1844. Queen
Victoria's coronation was about 1847 and she reigned into the 1900s
beginning while radio was first demonstrated as a communications
means in 1896. Among the PCTAs there is a terrible radio
"victorianism" both in technology and morality...the chronology and
subsequent utterances of those PCTAs is too coincident to overlook!

In this arena of PCTA radio-backwoodsmen (who can manually fell
giant redwoods in their fantasies), there can be NO talk of what
any radio service is doing other than what is blessed and codified by
the league. [see numerous utterances of the resident gunnery nurse]

"Shannon?" Who's he? He didn't have a DXCC, hasn't worked a DX
contest, isn't a dues-paying league member. Claude Elwood is "SK"
bless his joyful soul, but he did establish the relationships, the
framework on getting the highest data (of any kind, not just teleprinter)
through any given bandwidth on any communication circuit. No village
smithy anvils needed to bang out wireline morse on a solid-state
radio and pretend to be "advancing the state of the radio art." :-)

[expletive deleted]

[morse testing deleted]

[more expletives!...:-) ]

LHA / WMD


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