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-   -   I want to see SHF FM video signals. (https://www.radiobanter.com/shortwave/120151-i-want-see-shf-fm-video-signals.html)

Rich Grise June 8th 07 07:24 PM

I want to see your head on a pike.
 
None of this crap belongs in sci.electronics.basics.

On Fri, 08 Jun 2007 11:04:58 +0100, Robert Peffers. wrote:


"labtech_one" wrote in message
...

"default" wrote in message
...

SNIP

In all fairness it is/was our fault. Theoretically (in a democracy)
the people rule. We must really like the idea of war . . . --


in all fairness, the USA is a REPUBLIC, not a democracy. (Majority does
NOT always rule)




Is there anything to prevent a republic also being democratic?

As far as I know there are two definitions of, "Republic", 1. A state
where supreme power is held by the people, or their elected
representatives, or by an elected or nominated president. 2. Literally it
means a society with equality between its members.

While a democracy is -
1. (a), a system of government by the whole population, usu. through
elected representatives. (b), a state so governed. (c), any organization
governed on democratic principles.
2. an egalitarian and tolerant form of society.

Can any USAsian really believe that they live in a Republic, (in the
literal sense of the word)?

Can any USAsian really believe that they live in a "Democracy", (in the
literal sense of the word)?

In effect both the USA and the UK are now, "Oligarchies"-

Oligarchy,
1 government by a small group of people. 2 a state governed in this way.
3 the members of such a government.

Just consider how Bush and Blair took our two countries into wars that the
public, by the large, did not want and you will see that neither state is
either democratic nor republican.

We elect these people as our servants to carry out our democratic wishes
and they then become the masters and we the servants. It is long past time
for the people of both democracies to reassert themselves and demand their
appointed servants remain their servants rather than their leaders and/or
masters.

Will I now have to beware of black 'copters at dawn?



Rich Grise June 8th 07 07:26 PM

I want to see your head on a pike.
 
None of this crap belongs in sci.electronics.basics.

On Fri, 08 Jun 2007 13:05:11 +0100, Ian Jackson wrote:

In message , Robert Peffers.
writes


As far as I know there are two definitions of, "Republic", 1. A state
where supreme power is held by the people, or their elected
representatives, or by an elected or nominated president. 2. Literally it
means a society with equality between its members.

Does it 'literally' not mean a 'public thing', or 'a thing of the people'
(from your actual Latin 'res publicae')?

Ian.



Rich Grise June 8th 07 07:26 PM

I want to see your head on a pike.
 
None of this crap belongs in sci.electronics.basics.

On Fri, 08 Jun 2007 06:57:37 -0700, Anim8rFSK wrote:

In article ,
"Robert Peffers." wrote:

"labtech_one" wrote in message
...

"default" wrote in message
...

SNIP

In all fairness it is/was our fault. Theoretically (in a democracy)
the people rule. We must really like the idea of war . . . --


in all fairness, the USA is a REPUBLIC, not a democracy. (Majority
does NOT always rule)




Is there anything to prevent a republic also being democratic?


Yes

As far as I know there are two definitions of, "Republic", 1. A state
where supreme power is held by the people, or their elected
representatives, or by an elected or nominated president. 2. Literally
it means a society with equality between its members.


Neither of which is the definition of Republic.

While a democracy is -
1. (a), a system of government by the whole population, usu. through
elected representatives. (b), a state so governed. (c), any organization
governed on democratic principles.
2. an egalitarian and tolerant form of society.


Well, you got that wrong as well.

Can any USAsian really believe that they live in a Republic, (in the
literal sense of the word)?


Sure. We do.

Can any USAsian really believe that they live in a "Democracy", (in the
literal sense of the word)?


Yes. Many many many people incorrectly believe that. The press insists
on getting it wrong every day.

In effect both the USA and the UK are now, "Oligarchies"-


Except for the part where we're not.

Oligarchy,
1 government by a small group of people. 2 a state governed in this way.
3 the members of such a government.

Just consider how Bush and Blair took our two countries into wars that
the public, by the large, did not want and you will see that neither
state is either democratic nor republican.


Even if your statement were true, your conclusion still wouldn't be.

We elect these people as our servants to carry out our democratic wishes
and they then become the masters and we the servants. It is long past
time for the people of both democracies to reassert themselves and
demand their appointed servants remain their servants rather than their
leaders and/or masters.

Will I now have to beware of black 'copters at dawn?


I'm sure your level of dishonesty and delusion requires it.



Rich Grise June 8th 07 07:26 PM

I want to see your head on a pike.
 
None of this crap belongs in sci.electronics.basics.

On Fri, 08 Jun 2007 06:23:11 -0400, default wrote:

On Thu, 7 Jun 2007 21:57:17 -0400, "labtech_one"
wrote:


"default" wrote in message
. ..

SNIP

In all fairness it is/was our fault. Theoretically (in a democracy)
the people rule. We must really like the idea of war . . . --


in all fairness, the USA is a REPUBLIC, not a democracy. (Majority does
NOT always rule)

A democratic republic - or as the decider is fond of saying a "democracy."

We are "bringing democracy to Iraq." Hear it over and over.

More like bringing hypocrisy, but they prefer to use "democracy."



Bob Myers June 8th 07 07:38 PM

I want to see SHF FM video signals.
 

"Radium" wrote in message
ups.com...
Hi:

Video signals for NTSC, PAL, and SECAM television are transmitted on
AM carriers.


No, they're not. And there's no such thing as an "AM carrier"
or "FM carrier" to begin with. The carriers themselves are simply
signals at a given frequency. "AM" or "FM" refers to the modulation
IMPOSED on those carriers - in other words, how the information
to be carried is used to modify some aspect of the carrier signal.

In TV, most systems employ a version of AM to carry the luminance
(Y) signal; the color (chroma) information is carried via a somwhat
different version of AM, and the audio is most commonly FM.
The French SECAM system as originally implemented carried the
chroma information on TWO frequency-modulated subcarriers.


My question is, let's say I have a television set that is capable of
receiving and demodulating FM video carrier waves. What would I see on
the TV? I am aware that no company uses FM video. Would I see sawtooth-
like patterns on the screen due to frequency-modulated electric fields
present in the environment?


No.

I'd really like buy a TV with a FM-video receiver; I want to find out
what FM-video disturbances in the SHF [Super High Frequency ]
frequency-range look like. I am sick n' tired of AM video.

AM should be used for analog audio. FM should be used for digital
video.


Nonsense. The choices of AM and FM within the original analog
standard definitions were made for some very, very good reasons.
Digital television is a completely different beast, and is presently
broadcast using two very different modulation schemes - the
U.S. standard (ATSC) using 8-VSB, while the rest of the world
(mostly) will be using COFDM under the DVB-T standard.

Bob M.



No Name June 8th 07 08:59 PM

I want to see your head on a pike.
 
On Fri, 8 Jun 2007 11:04:58 +0100, "Robert Peffers."
wrote:

in all fairness, the USA is a REPUBLIC, not a democracy.
(Majority does NOT always rule)




Is there anything to prevent a republic also being democratic?



The Republican Party !


rj

Radium[_2_] June 8th 07 09:55 PM

I want to see SHF FM video signals.
 
On Jun 6, 10:35 pm, "Smarty" wrote:
Radium,

Some television is actually transmitted using FM modulation schemes, but not
for commercial broadcasting. Examples of FM TV are ham/amateur ATV/SSTV,
unlicensed 2.4 GHz surveillance links, and a number of point to point and
studio to transmitter systems. FM signaling provides benefits in noise
immunity and also permits better channel re-use, since it exploits one of
the best features of FM called "the FM capture effect", wherein nearly equal
strength signals which would otherwise interfere in AM systems will cause an
FM receiver to "capture" only the stronger signal and ignore the weaker,
even if differences of 1 dB of signal strength exists.

There is no specific answer to what you would see as far as video patterns,
and there is no reason whatsoever to expect to see sawtooth waveforms in
particular. The demodulated signal from FM will conform to the spectral
changes just as the demodulated signal from an AM detector would conform to
amplitude changes, and random noise would be considered "snow" in either
case. Unless a transmitted signal with a frequency ramp (sometimes called "a
chirp") is present, the video would have no sawtooth. A Doppler radar, for
example, could generate such a waveform, since some radars create chirped /
swept signals. The video scan rate(s) would additionally need to be in the
range of the chirp rate to create the appearance of a sawtooth.

FM disturbances in the SHF band are likely to be man-made and not
atmospheric, and thus only "viewable" if the "FM Video Receiver" you
envision had a demodulator / discriminator whose bandwidth was tailored to a
specific transmitted waveform, and even then only if sweep rates were
suitable. Absent a man-made transmitter, the SHF environment is mostly
thermal noise (both circuit and atmospheric) and only a radio telescope or
other enormous aperture / antenna will see beyond the atmosphere.

The choice of using AM versus FM is really way more complicated than "AM for
audio" or "FM for digital video". When designing communication systems of
any type, the engineer is faced with balancing many issues, and the channel,
media, noise environment, interference sources, power budget, multipath,
complexity, and cost are only a few of the considerations involved. A highly
reliable cable modem to transmit fast digital content may indeed by phase
modulated with an amplitude trellis; a secure and interference resistant
link may use spread-spectrum frequency hopping AM for digital signaling; and
FM winds up being used heavily in many voice communication systems mostly
because the capture effect reduces co-channel interference.

The closest I can suggest to what you might enjoy exploring would be a
satellite dish and receiver designed for L band which will see and decode
some broadcasting which is unprotected / unencrypted. It gets you into the
range of SHF, has true TV signaling for public viewing, and is a hobbyist
activity with others involved.


Smarty, big thanks for your detailed response. One big advantage [that
I could imagine] to using FM -- instead of AM -- to carry the
luminance (Y) signal, is that you can run on your treadmill without
seeing those lines on the screen mask your favorite shows. The
magnetic signals generated by the electronics in the treadmill causes
blinding interference on AM video. FM video is be immune to such
disruptions.


Radium[_2_] June 8th 07 09:58 PM

I want to see SHF FM video signals.
 
On Jun 8, 11:38 am, "Bob Myers" wrote:
"Radium" wrote in message

ups.com...

Hi:


Video signals for NTSC, PAL, and SECAM television are transmitted on
AM carriers.


No, they're not. And there's no such thing as an "AM carrier"
or "FM carrier" to begin with. The carriers themselves are simply
signals at a given frequency. "AM" or "FM" refers to the modulation
IMPOSED on those carriers - in other words, how the information
to be carried is used to modify some aspect of the carrier signal.


Okay. Thanks for clearing this up.

In TV, most systems employ a version of AM to carry the luminance
(Y) signal; the color (chroma) information is carried via a somwhat
different version of AM, and the audio is most commonly FM.
The French SECAM system as originally implemented carried the
chroma information on TWO frequency-modulated subcarriers.


Why not carry the luminance-signal on FM and the audio-signal on AM?

I'd really like buy a TV with a FM-video receiver; I want to find out
what FM-video disturbances in the SHF [Super High Frequency ]
frequency-range look like. I am sick n' tired of AM video.


AM should be used for analog audio. FM should be used for digital
video.


Nonsense. The choices of AM and FM within the original analog
standard definitions were made for some very, very good reasons.
Digital television is a completely different beast, and is presently
broadcast using two very different modulation schemes - the
U.S. standard (ATSC) using 8-VSB, while the rest of the world
(mostly) will be using COFDM under the DVB-T standard.


Couldn't FSK [the digital equivalent of FM] be used for luminance [Y]
signal of the digital video?


Brenda Ann June 8th 07 10:19 PM

I want to see SHF FM video signals.
 

"Radium" wrote in message
oups.com...

In TV, most systems employ a version of AM to carry the luminance
(Y) signal; the color (chroma) information is carried via a somwhat
different version of AM, and the audio is most commonly FM.
The French SECAM system as originally implemented carried the
chroma information on TWO frequency-modulated subcarriers.


Why not carry the luminance-signal on FM and the audio-signal on AM?


The reasons (primarily) behind using the AM visual and FM aural signals for
television a

Visual: Bandwidth. Visual uses what is called 'vestigial sideband'. This
means that basically only one sideband carries the modulation, with only a
vestige of the other sideband remaining, thereby reducing the bandwidth
needed for the visual signal by a significant factor. If FM were used, the
entire symmetrical waveform would have to be used, and would use a lot more
bandwidth. (Analog satellite television does/did use FM modulation, on the
order of 36 MHz IIRC, but bandwidth in the GHz ranges isn't at as much of a
premium as on relatively crowded VHF and UHF frequencies

Aural: Coverage. The aural signal (which is sent separately from the visual)
is only about 10% of the power of the visual signal.



Robert Peffers. June 8th 07 10:47 PM

I want to see your head on a pike.
 

"Ian Jackson" wrote in message
...
In message , Robert Peffers.
writes


As far as I know there are two definitions of, "Republic",
1. A state where supreme power is held by the people, or their elected
representatives, or by an elected or nominated president.
2. Literally it means a society with equality between its members.

Does it 'literally' not mean a 'public thing', or 'a thing of the people'
(from your actual Latin 'res publicae')?

Ian.
--

republic / n.
1 a state in which supreme power is held by the people or their elected
representatives or by an elected or nominated president, not by a monarch
etc.
2 a society with equality between its members (the literary republic).
[French république from Latin respublica, from res 'concern' + publicus
public]

A, "Cut & Paste", from Concise Oxford Dictionary.
--

Robert Peffers,
Kelty,
Fife,
Scotland, (UK).




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