(Robert Hovland) wrote in message ...
Dear Newsgroup,

Does anyone know the latest info about what is going to happen to the FM
band when the FCC forces all of the VHF television stations to give up
their broadcast band and switch to the new freqency allocations for
digital TV? As you may or may not know, the FM band is located in between
channels 6 and 7, I believe, and I would be surprised if the FCC would
leave the FM band alone when the TV stations get out. They want to
auction these soon-to-be-obsolete TV channel frequencies off to the
highest bidder.

This is an absurd notion, based on a lack of understanding.

There is a big chunk of spectrum between channels 6 and 7.

FM broadcast band 88-108MHz

The aero band, 108 to 136MHz or so.

Whatever is between 136 and 144MHz

2 meter amateur band, 144 to 148MHz

"Public service band" 148 to 174MHz
(I've lumped a lot here; paging, fire and police (at least in the
old days, MURS, the VHF marine band, the weather service broadcasts,
business use, etc).

Then comes channel 7.

So if they took the FM band away, there would still be a large chunk
there.

Take note that there is a 6MHz gap, a whole channel, between channels
4 and 5, which actually would be "in the way" more than the FM
band clustered with those other services that will not move.

What you also miss is the amount of spectrum that would be released
if TV vacated from the VHF frequencies (which the other posters
have indicated will not happen). 72MHz would be free, which is
in fact a massive amount of spectrum. TV is the widest bandwidth
signal commonly used, and you can fit an awful lot of stations in the
6MHz bandwidth used by one channel, the moreso now as schemes have
come into play to make better use of the spectrum for two way
communication.

So if the tv channels were released for other uses, a measly 20MHz
for the FM band is nothing.

Even if none of this was true, except for TV there is very little
need for continuous spectrum. So six MHz here, and six MHz there
will result in 12MHz available, and they do not have to be adjacent.
What we have seen is TV getting in the way. They were allocated over
fifty years ago, when radio was still relatively unused. They took
up large chunks of the VHF spectrum, no other service has so much
allocation in the 30 to 300MHz range, and so whatever came later
had to be fitted into whatever segments remained. Once the spectrum
was full, there was no more space to put anything, even though in any
given location there was always space lying empty, since no area has
all tv channels in use. The other services don't need so big chunks,
but TV is using any available space.

In other words, even if the tv channels were vacated for other uses,
there is no reason to lump the FM broadcast band with them.

Michael

In article , (Michael Black) wrote:

Take note that there is a 6MHz gap, a whole channel, between channels
4 and 5, which actually would be "in the way" more than the FM
band clustered with those other services that will not move.

Isn't that a 4 mHz gap, not 6 mHz, between channels 4 and 5 that whatever
takes up?


Regards,

John Byrns


Surf my web pages at, http://users.rcn.com/jbyrns/

John Byrns wrote:
In article , (Michael Black) wrote:


Take note that there is a 6MHz gap, a whole channel, between channels
4 and 5, which actually would be "in the way" more than the FM
band clustered with those other services that will not move.


Isn't that a 4 mHz gap, not 6 mHz, between channels 4 and 5 that whatever
takes up?

Ch 2 - 54-60 mHz
Ch 3 - 60-66 mHz
Ch 4 - 66-72 mHz

72-76 - used by pagers, model airplanes, etc.

Ch 5 - 76-82 mHz
Ch 6 - 82-88 mHz
FM Band - 88 - 108 mHz
etc.

John Byrns ) writes:
In article , (Michael Black) wrote:

Take note that there is a 6MHz gap, a whole channel, between channels
4 and 5, which actually would be "in the way" more than the FM
band clustered with those other services that will not move.

Isn't that a 4 mHz gap, not 6 mHz, between channels 4 and 5 that whatever
takes up?

You're right, I was looking at the chart wrong.

Michael

AHH FYI, There is only 4 MHz between TV 4 and 5....
72-76 MHz....not 6 MHz! Used for radio links (only is areas where TV 4
and 5 are not allocated/used) and model remote controls.

136-144 is government use....satellites (wx, etc) MARS, CAP, etc...even
Russia's MIR used 143.625 MHz as a comm channel....

Chris
WB5ITT
wb5itt sub for Nospam above
Houston

Michael Black wrote:

Whatever is between 136 and 144MHz

Take note that there is a 6MHz gap, a whole channel, between channels
4 and 5, which actually would be "in the way" more than the FM

"Chris Boone" wrote in message
...
AHH FYI, There is only 4 MHz between TV 4 and 5....
72-76 MHz....not 6 MHz! Used for radio links (only is areas where TV 4
and 5 are not allocated/used) and model remote controls.

Are there still 75 MHz fan markers of airport instrument approaches?
[Showing my age.]

No such proposal has been made. Digital FM has already been introduced on
the
existing 88-108 Mhz band.


"Robert Hovland" wrote in message
...
Dear Newsgroup,

Does anyone know the latest info about what is going to happen to the FM
band when the FCC forces all of the VHF television stations to give up
their broadcast band and switch to the new freqency allocations for
digital TV? As you may or may not know, the FM band is located in between
channels 6 and 7, I believe, and I would be surprised if the FCC would
leave the FM band alone when the TV stations get out. They want to
auction these soon-to-be-obsolete TV channel frequencies off to the
highest bidder.

The consequences I think of when I consider the moving of the FM band are
monstrous: what about all of the car radios, portable FM radios and
walkmen, and collector hifi FM tuners that will suddenly become unusable
without maybe some kind of adaptor which may or may not work very well?

To me, it just doesn't seem right that we need to have change for the sake
of "progress", unless the progress is real and necessary. Many times it
seems that these huge changes in the basic infrastructure of our
communications industry are done for the sake of the economic enrichment
of those companies who stand to profit richly from such a change, without
giving much, or any, consideration to the consequences.

When a land developer decides to make major changes to a piece of
undeveloped land, an environmental impact report has to be made before the
developer can go ahead with their plans. Where is the impact report for
this huge planned change in the FM band?

I would like to get comments from others who know more about this proposed
change and when it is to occur.

On Mon, 16 Feb 2004 03:06:59 +0000, Robert Hovland wrote:

Dear Newsgroup,

Does anyone know the latest info about what is going to happen to the FM
band when the FCC forces all of the VHF television stations to give up
their broadcast band and switch to the new freqency allocations for
digital TV? As you may or may not know, the FM band is located in between
channels 6 and 7, I believe, and I would be surprised if the FCC would
leave the FM band alone when the TV stations get out. They want to
auction these soon-to-be-obsolete TV channel frequencies off to the
highest bidder.

Who would be interested in this spectrum if its not used for Broadcast?
Not real practical for a mobile communications use since most systems now
use hand held radios and antennas at this band are not user friendly.
Maybe Rural high-speed Internet services?


The consequences I think of when I consider the moving of the FM band are
monstrous: what about all of the car radios, portable FM radios and
walkmen, and collector hifi FM tuners that will suddenly become unusable
without maybe some kind of adaptor which may or may not work very well?

To me, it just doesn't seem right that we need to have change for the sake
of "progress", unless the progress is real and necessary. Many times it
seems that these huge changes in the basic infrastructure of our
communications industry are done for the sake of the economic enrichment
of those companies who stand to profit richly from such a change, without
giving much, or any, consideration to the consequences.

When a land developer decides to make major changes to a piece of
undeveloped land, an environmental impact report has to be made before the
developer can go ahead with their plans. Where is the impact report for
this huge planned change in the FM band?

I would like to get comments from others who know more about this proposed
change and when it is to occur.

Good day to all of you, guys.

I'm a newbie in communications and I do have some questions I hope you can help me answer. Maybe if you have time, I would really appreciate it.

Thanks in advance!

1. Give 5 other uses of FM broadcasting and discuss how FM is being used.
2. Why do we say that FM stereo broadcasting is using a Frequency Division Multiplexing? Explain.
3. Why is 19 kHz used as the carrier frequency of the FM stereo broadcasting, why not other frequencies?

On Wed, 9 Oct 2013 10:17:51 EDT, wrote:

Good day to all of you, guys.

I'm a newbie in communications and I do have some questions I hope you can help me answer. Maybe if you have time, I would really appreciate it.

Thanks in advance!

1. Give 5 other uses of FM broadcasting and discuss how FM is being used.
2. Why do we say that FM stereo broadcasting is using a Frequency Division Multiplexing? Explain.
3. Why is 19 kHz used as the carrier frequency of the FM stereo broadcasting, why not other frequencies?

3 First: FM broadcasts as defined many years ago can handle audio
frequencies much higher than human hearing, but the higher you go, the
more bandwidth is needed. So, you can send ultrasonic audio, but
still want to limit the overall bandwidth. 19 KHz is above normal
hearing, but not by much. Double 19 or 38 is used as the carrier for
the L-R channel. 19 is the pilot frequency, not the carrier. But,
the carrier is exactly twice the pilot. Regarding #2, I suppose some
might refer to it as Frequency Division Multiplexing because the
entire audio bandwidth is divided into different uses. 0 to upper
teens for L+R (monaural), 19 for the pilot. 38 + or - upper teens for
L-R, even higher for other purposes. However, I never heard it called
that. Regarding #1, others will have to answer.