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Are such radios sold in the USA via the internet? Is the station really
"fixed"? Someone gave my uncle a radio which is said to have a special
"chip" that receives a Greek radio station. He mentioned to me that years ago
he had another one that suddenly switched to a Philipine station and he gave
it to a Filipino colleague. Amazon and Alibaba have such Metrosonix radios
but not station specific, but also do not seem to allow being sold in the
USA. THe search terms I used were SCA FM radio.

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On Sat, 28 May 2016 23:26:44 +0000 (UTC),
wrote:

Are such radios sold in the USA via the internet? Is the station really
"fixed"? Someone gave my uncle a radio which is said to have a special
"chip" that receives a Greek radio station. He mentioned to me that years ago
he had another one that suddenly switched to a Philipine station and he gave
it to a Filipino colleague. Amazon and Alibaba have such Metrosonix radios
but not station specific, but also do not seem to allow being sold in the
USA. THe search terms I used were SCA FM radio.
- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist


Yes, but not quite in the way you describe:
https://en.wikipedia.org/wiki/Subsidiary_communications_authority
In the USA, additional SCA carriers used to be quite common on most FM
stations. They were used to subscription handle background music
(MUZAK), commercial free radio, and all kinds of data broadcasting
(stocks, paging, sports scores, traffic reports, etc).

Most of that died starting in about 2002 with the introduction of
digital FM radio.
https://en.wikipedia.org/wiki/HD_Radio
The IBOC signals occupy the spectrum just outside of the normal FM
stereo signals formerly occupied by SCA sub-carriers. SCA and IBOC
cannot coexist on the same frequency.

In the USA, FM broadcast channel spacing is 200KHz. Stations licenses
in a given geographic area are assigned on alternate 200KHz slots
giving broadcasters a 200KHz guard band to allow for junk receivers
with rather wide IF bandwidth. SCA sub-carriers never went above
about 80Khz, so there was no increase in occupied bandwidth. IBOC
changed all that by grabbing all the spectrum between +/-100kHz and
+/-200KHz:
http://802.11junk.com/jeffl/crud/KCSM.jpg
Such an IBOC transmitter is now transmitting on top of the adjacent
channels frequency. If the adjacent channel is not occupied, no
problem. If there's a station there, big problem.

In some parts of Europe, FM stations are assigned on 100KHz channel
spacing, making both SCA and IBOC an impossibility. I don't know
which countries are like that.

--
Jeff Liebermann

150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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On Sat, 28 May 2016, wrote:

Are such radios sold in the USA via the internet? Is the station really
"fixed"? Someone gave my uncle a radio which is said to have a special
"chip" that receives a Greek radio station. He mentioned to me that years ago
he had another one that suddenly switched to a Philipine station and he gave
it to a Filipino colleague. Amazon and Alibaba have such Metrosonix radios
but not station specific, but also do not seem to allow being sold in the
USA. THe search terms I used were SCA FM radio.

Tradionally SCA was used for "elevator music", it was a subcarrier on an
FM broadcast station, a way for the elevator music company to distribute
its product. You could build your own SCA adapters, once ICs came along
they were really common in the hobby magazines, but it was one of those
things that you couldn't share the results with someone else. It was for
private listening only.

But yes, then at some point it was a way for "ethnic" broadcasters to beon
the air without the expense of a full FM transmitter, or getting a
license. We had some of that here. I think the stations were hoping to
be the source of the radios with the adapters, an income stream ofsome
sort.

But I haven't heard of such things locally. One thing that happened in at
least one case was they were able to leap to their own transmitter (though
if I'm remembering right in that case, the station is now up for sale, it
not being profitable for that market). So maybe it was an intermediate
step, get the listeners, then jump to a full transmitter when you had the
listeners.

Michael

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Default Subarrier FM radio

wrote:

Are such radios sold in the USA via the internet? Is the station really
"fixed"? Someone gave my uncle a radio which is said to have a special
"chip" that receives a Greek radio station. He mentioned to me that years ago
he had another one that suddenly switched to a Philipine station and he gave
it to a Filipino colleague. Amazon and Alibaba have such Metrosonix radios
but not station specific, but also do not seem to allow being sold in the
USA. THe search terms I used were SCA FM radio.


I'd be kind of suprised if any of those stations were still active.

Here in Chicago, it was probably the early 90's that was the height of
popularity, I think there were 2 greek stations, one polish and 3 or 4
others that were probably used for pocket pagers (normally silent except for
bursts of tones or a data carrier).

The basic idea was the "broadcaster" would get the station from overseas
(probably via a C-Band dish/receiver) and rebroadcast it on someones sca
channel (an ordinary FM station set up for it). They would then rent the
modified radio for like $5 a month or sell you it with a "lifetime"
subscription for $100 or around there.

Usually the radios, which were cheap garbage imports, were fixed to the
primary channel by crazy glueing the tuning shaft or otherwise disabling the
tuner. The boards were just simple 4 wire things, power, ground, detector in
and audio out. Since they were meant as a dedicated service, there wasn't
any reason to make the radio work both ways, normal and special. These
were all handmade and varied quite a bit, depending on what make/models the
local wholesale importers had.

The adapters were numerous, the most basic/simple one used a PLL chip
(either NE565 or NE566, maybe) and off the shelf resistors and capacitors.
They usually worked well enough but had problems with leakage from the main
carrier. There was another design, I want to say MC1340 as the centerpeice
which had the best performance (dead quiet) but required custom rf coils and
oddball capacitors, still simple to build but upped the cost quite a bit.

In any case the boards were probably not even 2"x2" and were easily tucked
in somewhere, usually the battery holder (4xC or D cells).

As far as legality of them, although I don't think anyone considered them a
crime to own, you couldn't open up a cottage industry by building them and
selling them. There was no reason to stop anyone from making one, but they
fell into that gray area where selling one was in some violation of FCC
rules and regs for 3rd party interception of a private (or intended private)
broadcast.

The thing is, once the internet and access to it became the norm (early
2000's), I really don't think those rebroadcasters could survive. On nearly
any platform or device there is usually one or two applications available
for listening to radio stations from aroound the world, if not dozens of
websites that retransmit them.

I'd guess there are plenty of 80+ year old grandmothers from the old country
who can work turning on and off a radio rather than firing up a laptop but I
doubt there is enough to make any money off them.

-bruce

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On Sat, 28 May 2016 22:13:54 -0700 (PDT), wrote:

"SCA sub-carriers never went above
about 80Khz, so there was no increase in occupied bandwidth. IBOC
changed all that by grabbing all the spectrum between +/-100kHz and
+/-200KHz: "


I don't know how familiar you are with high end audio but there
are tuners out there that can switch between narrow and wide band IF,
and I think a few, very few, variable. The wider bandwidth results
in much lower distortion. However then there is more noise and
you need a stronger signal.


What little I've done with broadcast FM was at various radio stations
and designing some low end receivers. That was also long ago, so I'm
fairly well behind on the technology. However, if "high end" means
"high price", I've fixed a few of these systems:
http://www.elanhomesystems.com

If you've ever swept a decent analog FM receiver, you may have noticed
that the IF bandwidth is much wider than the occupied bandwidth
(200KHz) of the signal. In order to keep the group delay fairly
constant within the IF bandwidth, this was necessary. That meant that
while the audio was very good quality, the receiver would pickup junk
from adjacent channels. Sensitivity is limited by the receiver front
end and is unaffected by the wider bandwidth.

Roll forward a few decades and we are now blessed with all digital
receivers. The best example is the Sony XDR-F1HD tuner:
http://ham-radio.com/k6sti/xdr-f1hd.htm
http://www.amazon.com/Sony-XDR-F1HD-Radio-Discontinued-Manufacturer/dp/B00168Q248
These typically sell on eBay for $150 to $250 or $500 with some
necessary modifications. Seems to be a demand:
http://www.ebay.com/sch/i.html?_from=R40&_nkw=XDR-F1HD&LH_Complete=1&LH_Sold=1
The difference is that this receiver has a "brick wall" digital IF
filter that doesn't need to be excessively wide in order to get low
group delay and low distortion. The narrower bandwidth is also good
for reducing much of the alternate channel noise produced by IBOC (HD
Radio) signals.

Meanwhile, the lower end FM receivers are also deriving benefits from
digital IF and demodulators. The Sony tuner uses an NXP/Philips
SAF7730 chip while most of the low end stuff uses various Silicon Labs
AM/FM chips:
http://www.silabs.com/products/audio/fm-am-receiver/
http://www.silabs.com/products/audio/fmreceivers/
Basically, it's almost an SDR (software defined radio) with most
everything in a single chip. Tecsun uses these chips in their various
radios. Plugged into a proper audio amp and speakers, they sound very
good, with little IBOC junk from the adjacent channels. (Note: Not
all Tecsun radios use digital receiver chips).

Actually it is all going digital soon, a couple of countries are in
the process of that right now.


No, it's not, at least in the USA. The FCC, in its infinite wisdom,
has endorse exactly one proprietary and expensive standard (IBOC)
totally owned and licensed by iBiquity. As usual, half measures don't
work. In this case, the broadcast industry wasn't quite sure if they
were going to commit to doing IBOC, so instead of 100% digital FM,
iBiquity was forced to provide the half ass analog/digital compatible
system that we're cursed with today. Incidentally, the failed AM
stereo system following a similar life cycle demonstrating that the
FCC and the industry doesn't learn from their expensive mistakes.

In 2012, a made a graph of the number of HD Radio stations in the SF
Bay area and in the USA.
http://802.11junk.com/jeffl/crud/hd-radio-stations-calif.jpg
http://802.11junk.com/jeffl/crud/hd_radio_stations.jpg
http://www.stateofthemedia.org/2013/audio-digital-drives-listener-experience/9-number-of-stations-dropping-hd-outnumber-those-adopting-in-2012/
There's actually been a decrease in stations, that have unplugged
their HD Radio equipment since 2012 but I don't have numbers handy.

I know little (or nothing) of what's going on with DAB (digital audio
broadcasting) as it's not used in the USA:
https://en.wikipedia.org/wiki/Digital_audio_broadcasting

--
Jeff Liebermann

150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558


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In article ,
wrote:

Now, this digital information bothers high fidelity tuners. they are coming out with modifications to the
ones with the worst susceptibility. I mean even tuners built in the 1970s. Some of them were damn good. Now,
the digital information makes for like "hash" or whatever, an unpleasant background noise.

I saw a modification for it and surprising to me is it was not something to cut the IF bandwidth, it was
strictly in the ratio detector. It seems the newer quadrature detectors don't have much of a problem with
this, so far I saw.


The digital noise is commonly a problem as the result of the way
stereo demultiplexing works. The higher-frequency components of the
FM detector's output are mixed against the 38 kHz local oscillator,
thus doing an AM demodulation of the L-R subcarrier band which lies on
either side of 38 kHz.

Many MPX decoders use a simple switching-mixer architecture, and these
will end up detecting both the signal around 38 kHz, but also whatever
is present in the neighborhood of the third and fifth harmonic of 38
kHz. Since that's where the digital subcarriers often line, the
digital signal ends up as sideband noise in the L-R difference signal,
and (unless you switch the tuner to "mono") ends up in the left and
right channel audio.

There are a number of ways to fix this. One is to filter the FM
detector output signal before it goes to the MPX chip... either a
low-pass filter (knee somewhere about 60 kHz), or notch filters
centered on the odd harmonics of 38 kHz, or both.

Another approach is to demodulate the MPX signal using a design which
is inherently not sensitive to the 38 kHz harmonic regions... e.g. a
true multiplying mixer using a 38 kHz sinewave local oscillator
(rather than a square wave or switching design), or a Walsh-function
decoder using a stepped wave which has no 3rd or 5th harmonic
content (some Sansui tuners do this).

Modern DSP-based MPX decoders could do any of these.

http://ham-radio.com/k6sti/hdrsn.htm has a nice overview of the
problem and solutions.
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On Sun, 29 May 2016 11:13:09 -0700, (Dave
Platt) wrote:

http://ham-radio.com/k6sti/hdrsn.htm has a nice overview of the
problem and solutions.


That article is on HD Radio (IBOC, iBiquity, dismal radio, etc) and
not about conventional FM stereo. While the mechanism for generating
the noise that you don't want to hear is similar, the technology,
solutions, and sources of noise are quite different. For example,
there's no mixing required for the excessive occupied bandwidth of
IBOC to ruin your day.

Incidentally, Brian Beezley has written several other articles on HD
Radio and tuners:
http://ham-radio.com/k6sti/
See "HD Radio" section at lower right and various equipment reviews at
the upper right.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
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Interesting, in fact everybody, interesting.

Next we need a thread on what all they crammed into the NTSC TV signal. Like PRO audio which was another SAP essentially, the VITS or VIR, closed captioning, ghost cancelling reference and who knows what else.

Man's innate lust to cram as much as possible into any given bandwidth.

With TV, they wasted it. They went digital because NTSC takes too much bandwidth and has limited resolution. The problem is they cannot come up with any decent programming anymore.

In other words, the resolution doesn't matter if there's nothing to watch. I don't need 2,000 line resolution to watch Gunsmoke. Just like I don't need 24 bit/96 KHz sampling to listen to music from the 1960s.
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On Mon, 30 May 2016, wrote:

Interesting, in fact everybody, interesting.

Next we need a thread on what all they crammed into the NTSC TV signal.
Like PRO audio which was another SAP essentially, the VITS or VIR,
closed captioning, ghost cancelling reference and who knows what else.

Man's innate lust to cram as much as possible into any given bandwidth.

No. They had a system first in use in the late 1930s, and times changed.
but they didn't want to start again, so they added that stuff, don't
forget color came in the fifties, tacked onto the existing B&W standard,
but it never improved the picture quality (though no more fussing with the
vertical or horizontal hold controls, actually the tv set I got in 1982
didn't even have them (or at least not on the outside).

With TV, they wasted it. They went digital because NTSC takes too much
bandwidth and has limited resolution. The problem is they cannot come up
with any decent programming anymore.

I actually got my first tv set since 1982 because of the changeover. I
thought about just getting a converter, but decided spending a bit more
meant I got closed captioning, stereo sound, much better image quality,
and of course I got rid of the CRT and went to LCD.

In other words, the resolution doesn't matter if there's nothing to
watch. I don't need 2,000 line resolution to watch Gunsmoke. Just like I
don't need 24 bit/96 KHz sampling to listen to music from the 1960s.

I notice a difference. After 70 or so years, it made sense to actually
scrap the old and move into the future. One might hope that this
"standard" can be extended if needed, so there won't be a need to start
from scratch again in the future.

Michael



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On Monday, May 30, 2016 at 9:43:06 AM UTC-7, wrote:
With TV, they wasted it. They went digital because NTSC takes too much
bandwidth and has limited resolution. The problem is they cannot come
up with any decent programming anymore.

Digital would take more bandwidth, except they use compression to reduce the amount of data sent. In the 1950s, there was not enough computing power in the whole world to do the compression and decoding in real time.
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Wow! incredible answers, thanks


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http://www.panix.com/~vjp2/vasos.htm
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[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]




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"Actually, NTSC color makes pretty good use of bandwidth when you're
constrained to all-analog"


Right, but that is not what I meant. I meant none of this **** is worth watching. When I was a kid and we had like five channels we actually had to have a discussion on what to watch.

Now hot only are there more TVs in the house than people, we got like 500 channels. There used to be shows that were entertaining, even though they were kinda like - junk. They were entertaining. Now we are relegated to watching people remodel houses or something, or Gordon Ramsay bitching out restaurant owners or some retired detective describing a 35 year old case, with re-enactment of course. Most other shows it looks like they let an eight year old kid work the camera, I mean they do EVERYTHING cameramen were taught not to do. It is ****ing unwatchable.

In the 1960s and 1970s having a TV was a status symbol almost. Now, it has gotten so bad that NOT having one is, almost. Or at least leaving it turned off.

"When it was
introduced, compatible color was right at the cutting edge of (or maybe
a bit beyond) technical feasibility for commercial (not to say consumer)
electronics."


Actually it could not be beyond since it worked. It redefined the cutting edge. Color TV is one of the few things the US can claim as its own invention. Other countries came later, albeit with better systems, but I am pretty sure we were first.

I am not sure about FM stereo. Never really looked into it. I know that in Europe they use less modulation and thus less bandwidth. The de-emphasis is 50 uS not 75. I also had the US and European versions of the same album (Golden Earring - Moontan) and their version was cut with alot less groove modulation and had a huge leadout, putting most of the music where the groove velocity was greater and tracking error less. It sounded considerably better. I mean ALOT better.

Seems like the US is all about loud. More modulation, more up compression, and even other tricks to sound louder. Idiots will put their graphic equalizers full tilt up, and have no idea how to properly use a dynamic range expander like a Pioneer RG-1 or RG-2. They think the right way is to turn the input level all the way up. Look asshole, if it was meant to be all the way up all the time why did they even put a control there ?

But that is my opinion after much observation. LOUD is the "American" way. Wasn't it the US came out with laws about reporting the power output of amps ? I guess other countries have the same but that seems like something we probably did first.
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isw wrote: "In article ,
wrote:

Interesting, in fact everybody, interesting.

Next we need a thread on what all they crammed into the NTSC TV signal. Like
PRO audio which was another SAP essentially, the VITS or VIR, closed
captioning, ghost cancelling reference and who knows what else.

Man's innate lust to cram as much as possible into any given bandwidth.

With TV, they wasted it.


Actually, NTSC color makes pretty good use of bandwidth when you're
constrained to all-analog, vacuum-tube technology. When it was
introduced, compatible color was right at the cutting edge of (or maybe
a bit beyond) technical feasibility for commercial (not to say consumer)
electronics.

Isaac "

And ATSC 1.0 color gamut is actually a hair smaller than
that of the NTSC it replaced.


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"And ATSC 1.0 color gamut is actually a hair smaller than
that of the NTSC it replaced. "


You lost me there, what do you mean by that ? The different broadcasting format should have nothing to do with the colors that can be displayed, that is a function of the panel, or CRT. (actually a plasma panel is like a CRT in a way but it just has multiple rays)

Now LCD panels might be limited by the backlight. They cannot display any color that is not in the spectrum of the backlight. Actually they could not handle the colorimetry required for LED backlighting until recently when the new generation of LEDs cam out that actually have a phosphor.

Older LEDs had very spikey outputs. If a color isn't there you must display two colors opposite the wavelength you want in the right proportion so the eye mixes it. It was just too much to deal with so they went with the CCFLs.
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jurb...gmail.com wrote: "You lost me there, what do you mean by that ? The different broadcasting format should
have nothing to do with the colors that can be displayed,"

To the contrary. A display may be capable of limitless
color and dynamic range, but it can reproduce only
what it is sent.
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In article ,
wrote:

"Actually, NTSC color makes pretty good use of bandwidth when you're
constrained to all-analog"


Right, but that is not what I meant. I meant none of this **** is worth
watching. When I was a kid and we had like five channels we actually had to
have a discussion on what to watch.

Now hot only are there more TVs in the house than people, we got like 500
channels. There used to be shows that were entertaining, even though they
were kinda like - junk. They were entertaining. Now we are relegated to
watching people remodel houses or something, or Gordon Ramsay bitching out
restaurant owners or some retired detective describing a 35 year old case,
with re-enactment of course. Most other shows it looks like they let an eight
year old kid work the camera, I mean they do EVERYTHING cameramen were taught
not to do. It is ****ing unwatchable.

In the 1960s and 1970s having a TV was a status symbol almost. Now, it has
gotten so bad that NOT having one is, almost. Or at least leaving it turned
off.

"When it was
introduced, compatible color was right at the cutting edge of (or maybe
a bit beyond) technical feasibility for commercial (not to say consumer)
electronics."


Actually it could not be beyond since it worked.


What I meant was that it worked a lot better in the lab when being
tended by skilled technicians that it did in domestic homes when not
being tended at all. It was somewhat "drifty" and needed a lot of
tweaking.

It redefined the cutting
edge. Color TV is one of the few things the US can claim as its own
invention. Other countries came later, albeit with better systems, but I am
pretty sure we were first.


If you're talking about PAL, which came later, quite good arguments can
be made that it's not better at all; just that its weaknesses are in
different places.

Isaac
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"If you're talking about PAL, which came later, quite good arguments can
be made that it's not better at all; just that its weaknesses are in
different places."


Well for one they eliminated the phase control. On US sets it was called the tint or hue control and it shifted the phase of either the chroma subcarrier or the oscillator. Their little scheme cancelled out the errors, which were mainly caused by poor frequency response which would shift the phase of the burst or even make the PLL in the TV have a phase error because part of the burst is cut off. However it happened, you sometimes needed to adjust the tint in the old days.

Also, PAL was more lines. I think it was 50 Hz which would mean they needed a longer persistence phosphor. Also the horizontal rate was faster. They had quite a bit more resolution bt at the cost of frame rate.

But that can be dealt with, you know movies in the theaters only used to be 24 frames per second right ? Well people did not really have a problem with that. They only reason it is a problem with a CRT is because the picture is drawn in a series of lines and that makes it more visible. A film projector is a whole different animal than a TV set.
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"To the contrary. A display may be capable of limitless
color and dynamic range, but it can reproduce only
what it is sent. "


Why wouldn't they send it ?


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2:40 wrote:
"To the contrary. A display may be capable of limitless
color and dynamic range, but it can reproduce only
what it is sent. "


"Why wouldn't they send it ? "

sigh... Simple: The color gamut triangle of
the ATSC *standard* - what the STANDARD
is capable of reproducing - is a tad smaller
than that of NTSC.
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thekma @ gmail.com wrote in message
...
2:40 wrote:
"To the contrary. A display may be capable of limitless
color and dynamic range, but it can reproduce only
what it is sent. "


"Why wouldn't they send it ? "

sigh... Simple:


Not as simple as you say.

The color gamut triangle of
the ATSC *standard* - what the STANDARD
is capable of reproducing -


ATSC has no standard color gamut. Even with caps-lock, there is no
STANDARD color gamut in ATSC. Rec. 709 is common for HD programming,
and Rec. 601 is common with SD. But ATSC doesn't care; the primaries
and the white point are specified in the stream. Maybe someday Rec,
2020 will be standard in a future version of ATSC, but for now, there
is no such thing as an ATSC standard color gamut.

is a tad smaller than that of NTSC.


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..... wrote: "STANDARD color gamut in ATSC. Rec. 709 is common for HD programming,
and Rec. 601 is common with SD. But ATSC doesn't care; the primaries
and the white point are specified in the stream. Maybe someday Rec,
2020 will be standard in a future version of ATSC, but for now, there
is no such thing as an ATSC standard color gamut.
- show quoted text -"

Butt the f out!

Find someone worthwhile to stalk.
Like someone you actually know.
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wrote in message
...
.... wrote: "STANDARD color gamut in ATSC. Rec. 709 is common for HD
programming,
and Rec. 601 is common with SD. But ATSC doesn't care; the primaries
and the white point are specified in the stream. Maybe someday Rec,
2020 will be standard in a future version of ATSC, but for now,
there
is no such thing as an ATSC standard color gamut.
- show quoted text -"

Butt the f out!

Find someone worthwhile to stalk.
Like someone you actually know.


Sorry to disturb you with the simple facts concerning color gamuts in
video standards. But there is no ATSC color gamut standard. NTSC has a
very broad gamut, but NTSC is dead. Pointer's gamut is probably
adequate for practical use. But ATSC doesn't care. It expect the
primaries and white point to be specified in the stream; it's doesn't
define them as a standard.

You are obviously way too smart to understand that. Primary colors.
White point. Pretty simple stuff.

HFCUIS. LKF. FCK,WAFA. AASBDF. OK, li'l buddy?

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In article ,
wrote:

"If you're talking about PAL, which came later, quite good arguments can
be made that it's not better at all; just that its weaknesses are in
different places."


Well for one they eliminated the phase control. On US sets it was called the
tint or hue control and it shifted the phase of either the chroma subcarrier
or the oscillator. Their little scheme cancelled out the errors, which were
mainly caused by poor frequency response which would shift the phase of the
burst or even make the PLL in the TV have a phase error because part of the
burst is cut off. However it happened, you sometimes needed to adjust the
tint in the old days.


The Phase Alternation dropped the lowest interlace rate from NTSC's ~15
Hz to ~6.25 Hz, which is really visible and was responsible for PAL's
well known "high brightness flicker".

Also, PAL was more lines. I think it was 50 Hz which would mean they needed a
longer persistence phosphor. Also the horizontal rate was faster. They had
quite a bit more resolution bt at the cost of frame rate.


Higher spatial resolution, lower temporal resolution. Probably a wash.

But that can be dealt with, you know movies in the theaters only used to be
24 frames per second right ?


Actually, 48 FPS as projected -- each frame was shown twice.

Well people did not really have a problem with
that. They only reason it is a problem with a CRT is because the picture is
drawn in a series of lines and that makes it more visible.


It's actually just because it's a much lower rep rate. See my comment on
PAL's interlace problem. A longer persistance phosphor would have helped
the flicker problem, but would have caused motion blur.

Isaac


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"Actually, 48 FPS as projected -- each frame was shown twice. "

Didn't know that. Makes sense though.

I busted "them". I believe it was a commercial for a Sharp camcorder with good low light capabilities. They were showing what was ostensibly some kids birthday party or something. Well back then I always had six or seven head VCRs. I could tell when they pulled it down from the 48 Hz to 60 Hz. They showed each from twice but every so many cycles they would show it thrice.

The video the showed was clearly on film because a camcorders does not use 24 FPS. (or 48)

Nothing happened, WTF. I didn't buy one, I didn't initiate a class action lawsuit, in fact it is almost like who cares.

Like now, I work on "pro" audio. Know what "pro" actually means here ? It means that the FTC and IHF standards do not apply. You got an amp the has 55 volt rails which yields about 100 WPC but they can call it 3,500 watts. Technical Pro is one of the worst offenders but I have seen worse. I saw one amp supposedly 1,000 watts that had a single TO-220 type chip output. There is no way this thing was even 100 WPC.

But anyway, it is not the same with a DVD, with a good four (plus two audio) head VCR going frame by frame you can see the effect. Two frames would be the same and then three frames would be the same. And I am probably the only person in the world who knows they cheated.

Technically, if their camcorder would work in as low light as that film it was not false advertising, and I really don't recall them saying the video was taken with their camcorder. But the implication was pretty strong. Come on, they are advertising a camcorder with good low light sensitivity, What does the viewer think when he sees a kids birthday party ?

Just another example of the **** they can get away with. But the bottom line is I am so close to not giving a **** I can smell it.
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In article ,
wrote:

"Actually, 48 FPS as projected -- each frame was shown twice. "


Didn't know that. Makes sense though.

I busted "them". I believe it was a commercial for a Sharp camcorder with
good low light capabilities. They were showing what was ostensibly some kids
birthday party or something. Well back then I always had six or seven head
VCRs. I could tell when they pulled it down from the 48 Hz to 60 Hz. They
showed each from twice but every so many cycles they would show it thrice.

The video the showed was clearly on film because a camcorders does not use 24
FPS. (or 48)

Nothing happened, WTF. I didn't buy one, I didn't initiate a class action
lawsuit, in fact it is almost like who cares.

Like now, I work on "pro" audio. Know what "pro" actually means here ? It
means that the FTC and IHF standards do not apply. You got an amp the has 55
volt rails which yields about 100 WPC but they can call it 3,500 watts.
Technical Pro is one of the worst offenders but I have seen worse. I saw one
amp supposedly 1,000 watts that had a single TO-220 type chip output. There
is no way this thing was even 100 WPC.

But anyway, it is not the same with a DVD, with a good four (plus two audio)
head VCR going frame by frame you can see the effect. Two frames would be the
same and then three frames would be the same. And I am probably the only
person in the world who knows they cheated.


That's not "cheating"; it's just the standard "two-three pulldown"
technique (known as "telecine") that NTSC (but not PAL) used to convert
24 FPS movies to ~30 FPS video. It wasn't frames that were repeated,
though; it was fields (a "field" consists of either the odd-numbered
lines, or the even-numbered ones).

If you numbered fields sequentially, it went
1-1-2-2-2-3-3-4-4-4-5-5-6-6-6- ...

Worked pretty well but added a motion artifact known as "judder" because
of the irregularity. It did have the advantage of making the sound run
at the proper speed (and incidentally make the movie have the "proper"
running time).

PAL, OTOH, just overcranked the film from 24 to 25 FPS. The audio
pitches were slightly too high, people talked slightly faster, and the
film was over slightly quicker.

The 2-3 pulldown worked quite well for analog TV, but gave the MPEG
folks fits until they finally realized what was messing up their
encoding efficiency. MPEG encoding is all about finding regularities and
exploiting them, but:

If you take that field sequence
1-1-2-2-2-3-3-4-4-4-5-5-6-6-6- ...

and show it with the associated film frames:
1-1-2-2-2-3-3-4-4-4-5-5-6-6-6- ...
A-A-B-B-C-C-D-D-E-E-F-F-G-G-H ...

You see that once in a while a frame (e.g. "C") consists of two fields
*not* from the same frame, but from adjacent ones. This really messes
with the correlation between odd and even lines that makes MPEG work
well. Worse, if there is a scene change just at that point, the odd
lines and even lines are from totally different images.

The MPEG guys finally figured out that the best thing to do was just
reverse the whole process (inverse telecine) to get back to 24 "proper"
FPS with no irregular pulldown and no split frames, and then encode that.

Isaac
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Since it was on TV and not the silver screen, that implies that the recording was made on their camcorder. There would be no reason to transfer their camcorder tape to 24 FPS film.

They are busted.
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On Saturday, May 28, 2016 at 7:26:47 PM UTC-4, wrote:
Are such radios sold in the USA via the internet? Is the station really
"fixed"? Someone gave my uncle a radio which is said to have a special
"chip" that receives a Greek radio station. He mentioned to me that years ago
he had another one that suddenly switched to a Philipine station and he gave
it to a Filipino colleague. Amazon and Alibaba have such Metrosonix radios
but not station specific, but also do not seem to allow being sold in the
USA. THe search terms I used were SCA FM radio.

- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]


Visit Metrosonix.com, We manufacture and sell a wide variety of SCA radios.
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