Where is this spectrum supposed to come from?

[k4kyv]

I was  listening to a news item on the radio today about an upcoming FCC spectrum auction that is supposed to bring in billions of $$$ to the federal government when over-the-air TV stations change completely over to digital by 2009 as mandated by the FCC.

But the same over-the-air channels will still be broadcasting, including a main high-definition channel to carry the regular programming, plus parallel digital channels to carry additional programming such as foreign language channels and other special interest material.

Digital TV really works as long as the signal is strong enough.  This would be considered a "semi-fringe" area, with our nearest full-power TV station about 50 miles away as the crow flies.  The analogue signal may be snowy and full of sparklies from power line noise, but you can change to digital reception using the same antenna and get perfect picture quality.  The greatest problem is that when the signal level drops down below a certain threshold and too much of the streaming data is lost, the entire image and sound  intermittently disappear and the screen goes dark, so digital reception does not guarantee perfection.

But I am still wondering where this extra spectrum is supposed to come from after the conversion is complete.  Won't the present channels simply be re-occupied with digital instead of analogue modes of emission?  With audio (AM and FM radio) digital transmission takes up more bandwidth that the original analogue signal.  What am I missing?

[WU2D]

The FCC limits the bandwidth of american DTV called 8VSB to 6 MHz. Furthermore due to some foresight and fears of digital causing interference, the spurious responses of a DTV signal must be 16 dB lower than that of an analog signal. This is good news.

The american system uses an amplitude shift method which sends the signal representation with 8 discrete levels using AM. The original VSB filter idea developed for analog TV is employed to reduce the unwanted sideband. Think of this as digital AM. Of course video compression must be used to fit everything into 6 MHz!

The Euro version is many times more sophisticated and uses a multicarrier system called COFDM. COFDM is comparatively immune to multipath and thus can work in non-line-of-sight with primitive RX antennas.

The American version requires good antennas.

Mike WU2D

[WBear2GCR]

Dunno exactly, but I suspect that the space between digital signals can now be used freely, whereas it wouldn't quite fly with analog signals.

The good news, if there is any, is that Google is saying that before the FCC auctions the spectrum that they want the FCC to say that the spectrum must be shared and sold at "market rates" to any and all that want some of it... furthermore, my understanding is that if GOOGLE wins the auction they propose to make the spectrum FREE for wireless internet!!

Which for me would be good news - the idea is that they will make money on ads...

At least that is the way I understand the story.

                  _-_-bear

PS. got to see some HDTV over-the-air the other day at the neuveau doctor's office... problem was that the signal was just at the threshold, so it would pixelate and drop out, drop the pixture, keep the audio, etc... gone is snow and a listenable audio signal. All or NUTIN'!

[Blaine N1GTU]

from what i heard all station were migrating to UHF for digital
VHF will be unoccupied

[Tom WA3KLR]

We had a thread in the past on the HDTV allocations but I can't find it.

Channels 52 - 69 are being re-farmed for non-digital TV use.  That is where the new spectrum is coming from.  Yes the new digital tv transmissions presently on Ch. 52 and above will have to move down below 52.

The digital tv on UHF will be up to channel 51 only.  As far as I know, digital tv transmission on VHF is not outlawed but is deemed impractical on the lower VHF channels (2 - 6).  There may be some digital tv on the upper VHF channels.   There has been one of the few VHF digital broadcasts in this Allentown PA area.

One digital broadcast signal occupies 6 MHz bandwidth, same as the NTSC does.  However many independent channels of digital tv programs can be put in that space.  Most over-the-air HDTV broadcasts have 2 or 3 programs.  I have seen as many as 8 or 10 ? programs on one digital cable channel, but the resolution was poor.  The highest resolution 1080p HDTV takes up the whole channel but this is/will rarely be done.  Your "HDTV" is designed to accept a large number of digital formats.  Technically speaking HDTV refers to only the highest resolution formats of all of the digital tv formats. 

[Bill, KD0HG]

Hold on!

All analog TV completely goes away in 2009.

Every VHF TV transmitter in the US of A is turned off and sent to the scrap heap in 2009. (Unless sold to someone south of the border). There won't be any DTV on the old analog TV channels, it all migrates up to UHF.

That frees up that spectrum for sale.
54-88 MHz, 175-211 MHz. PRIME RF territory.
(Public safety, police, fire, etc., are going to get some of that spectrum).

I was recently talking to the CE of a Denver VHF TV station and he was joking about having to junk a several-hundred-thousand $ transmitter- Their entire analog TV transmission plant, line, batwing antenna, analog STL, all of it- junked.

I've been using digital FM (IBOC) for a couple of years now, and the same sort of thing is bloody annoying...Either you get perfect reception, or nothing. Since it takes a bit of time for the codecs to decode at the receiver, it's a real PITA trying to move an antenna around for best reception.

On the other side of the coin, anyone that's never seen digital TV or heard HD FM is in for a shock- They are freaking amazing.

The old allocations of VHF and UHF spectrum that have pretty much been in place since the late 1940s are being radically changed in February of 09.

[David, K3TUE]

All analog TV completely goes away in 2009.

That frees up that spectrum for sale.
54-88 MHz, 175-211 MHz. PRIME RF territory.
(Public safety, police, fire, etc., are going to get some of that spectrum).

This is what I heard.

The digital TV spectrum was already been allocated, so this is up fro grabs.

[Mike/W8BAC]

The good news, if there is any, is that Google is saying that before the FCC auctions the spectrum that they want the FCC to say that the spectrum must be shared and sold at "market rates" to any and all that want some of it... furthermore, my understanding is that if GOOGLE wins the auction they propose to make the spectrum FREE for wireless internet!!

Not exactly. Listen to the news piece from NPR here.

http://www.npr.org/templates/story/story.php?storyId=12344564

Google is involved in this mobile phone and wireless devise issue for the same reasons they are involved in the "Network Neutrality" issue. Let a small handful of companies control the content and bandwidth of your smart phone or computer and your freedom to choose will suffer.

It's really not that far fetched to think of finding some day a mailing from Comcast or Verison giving you your choices for TV, broadband, telephone and wireless phone. Kinda like a channel guide for each. You can have anything on the list (outside of your basic package) but it will cost you extra.

[Pete, WA2CWA]

And, after February 2009, in order to receive DTV over the airwaves with your "regular" analog TV, outside antenna, rabbit ears, etc., you're going to need "the box".

[KF1Z]

>>  "Dunno exactly, but I suspect that the space between digital signals can now be used freely, whereas it wouldn't quite fly with analog signals." <<


Oh great, just what we need....  TV Freebanders   !!!

;-)

[WA3VJB]

The Euro version is many times more sophisticated and uses a multicarrier system called COFDM. COFDM is comparatively immune to multipath and thus can work in non-line-of-sight with primitive RX antennas.

You're right Mike, another hi hi FB example (like Radio Mondial vs. Ibiquity) where the euros got one on us.

We use COFDM for wireless video, and it's a great system.

Full bandwidth, broadcast quality video/audio from a shoulder camera, and the ability to bounce the signal off buildings to get to the transmission truck or receive drop point.

Only problem for the crews is the extra draw on the camera battery and the extra weight of the thing.  Cold weather a fully charged Betacam SX is dead in 45 minutes.

"Sorry about that bumpshot, didn't know how long to wait."

So we end up with a grip dolly and 50lbs of batteries. Yes, very portable.

[W3LSN]

Don't throw out your VHF antennas yet! Low band VHF channels 2-6 have in fact been allocated for permanent DTV assignments and a handful of stations have elected to locate there because of lack of UHF alternatives. The channel election process running these past few years revealed that High band VHF 7-13 is the most popular choice with stations because it's more economical to run full-power transmitters there. High power UHF transmitters still typically run IOT tubes in their HPA's which cost more to maintain and operate. But since there are many more UHF channels to go around, the bulk of stations will end up on UHF below Ch-52 when the dust settles in 2009.

73, Jim
WA2AJM/3

[W9GT]

I'm kinda glad this subject came up for discussion.  I was involved with broadcast TV and delivery of network video/audio feeds to broadcast stations back in the "good old days" of NTSC (analog)......but I've been away from it for a long time.  I must admit, I have really lost track of the technology since the advent of digital video and HDTV.  Can anyone here give a short explanation of how the new system will work...where (what frequencies) the broadcast stations are moving to, and what they are changing?  What makes a "digital" tuner different?   Looks like we all will have to make the change to digital by 2009, either by buying new TVs or at a minimum getting a converter box.

73,  Jack, W9GT

[W3LSN]

I'm kinda glad this subject came up for discussion.  I was involved with broadcast TV and delivery of network video/audio feeds to broadcast stations back in the "good old days" of NTSC (analog)......but I've been away from it for a long time.  I must admit, I have really lost track of the technology since the advent of digital video and HDTV.  Can anyone here give a short explanation of how the new system will work...where (what frequencies) the broadcast stations are moving to, and what they are changing?  What makes a "digital" tuner different?   Looks like we all will have to make the change to digital by 2009, either by buying new TVs or at a minimum getting a converter box.

73,  Jack, W9GT

For the 80% of the country that get's its TV programming from cable of satellite, it won't make any difference.  Those people stuck with so-called OTA (over-the-air) TV will need to buy a new TV or a digital converter box. February 17, 2009 is the last day of NTSC TV analog broadcasting after which all those extra sets in your garage, workshop, and kids bedrooms will go to snow.

The old system is called NTSC. The USA has adopted a new digital transmission system called ATSC which uses MPEG-2 compressed digital video streams with 8-VSB modulation on terrestial transmitters. The cable industry is using COFDM for its digital systems.

ATSC will allow for broadcast of DTV in several different formats including HDTV and SDTV. The system also allows for multi-casting of several channels together on one carrier which some stations are now doing. This presents a problem of how to tune to the programs all of which is managed by a system called "PSIP" that enables a DTV receiver to identify program information and use it to create sophisticated electronic program guides.

DTV is also called the Television Engineer's Full Employment Act, which, as an FCC madate, incompatible with the previous system, has forced all TV broadcasters to replace their studio, distribution, and transmitter equipment.

There is plenty of info available on the web since this system has been in development for over 20-years. Just Google terms such as Digital Television, ATSC, DTV, or PSIP

73, Jim
WA2AJM/3

[K6IC]

As a bit of an aside,  Have been surprised that one can buy a perfectly adequate LCD HDTV for about $600,  out the door.  (37-inch).

And in the SF metro area,  a clip lead antenna provides abt 38 off air digital signals.  The uniformly "best" looking images come from PBS.

For me the $600.  was very well spent,  and will wait for things to settle to see what happens at the high end.

For fringe off air reception,  perhaps  some large RX antenna will yield something,  but may need to be LOS.

Just my OT observations.   YMMV   Vic  K6IC

[Pete, WA2CWA]

Lots of great info:
http://www.dtv.gov/

[AF9J]

Thanks Pete,

I forwarded the link to my home e-mail for future reference.

Ellen - AF9J
At work

[WB3LEQ]

About six months ago I did a search trying to find one of these digital converter set top boxes since WTAE in Pittsburgh supposedly is broadcasting in both digital and analog.  Found a model for Radio Shack but it was already discontinued, then Walmart had one that was also discontinued.  So who is selling this miracle set top box that the government will have a rebate for?  I still want one CHEAP!  I have a hunch that I'm located just far enough away that it won't work for me.

Bob

[K6IC]

Hi Bob,

Have spent very little time looking into HDTV,  was in market for new LCD TV,  for remote off-grid QTH,  so was just down to which one and what features.

Just Googled "set top hdtv converter"  and got hits from Circuit City,  Target etc.  Some of the results were were for "set top hdtv receiver"  You might try searching again ... things are changinr quickly.

Think that if you could go to Best Buy,  CC and WallyMart you might find one that you could try,  and "if not delighted,  you could return for cheerful refund" ...  mabe those days are gone.  Just make sure that you could return the item.  You might need an outdoor HDTV antenna if U are inna fringe area.

HDTV is coming,  and the price curve has come down in the past year.

GL  Vic  K6IC

[W9GT]

Lots of great info:
http://www.dtv.gov/

Thanks Pete!  That looks like a good site to provide the requested info.  It seems that there may be a lot of consumers that are not up to speed on this stuff.   As stated by others, however, a large percentage of viewers may not be affected unless cable/satellite companies require them to pay extra for the digital conversion.

73,  Jack, W9GT

[k4kyv]

Supposedly, the cable companies will continue to supply analogue signal to those who do not subscribe to digital service.

It will most likely become like touch tone dial telephone service.  A few years into the future, digital will be the standard format and most customers will be using digital TV's, and the cable company will have to go out of its way to supply analogue signal.  It will be cheaper for the cable company to supply a digital signal, but customers will still pay extra for "digital" service.

I'm not sure if our monthly phone bill still has a surcharge for touch tone service.

[W1DAN]

Hi all:

Note while DTV is being broadcast over the air and for free now (many people do not get this idea), many stations only up-convert their local newscasts and pass HD from the network. You will not get a High Definition picture at all times.

The FCC auction is big in silicon valley:

http://www.mercurynews.com/ci_6386609

Proposed "White spaces" have a good chance to interfering with the new DTV stations, similar to BPL.

The DTV transition may not happen in 2009 after all.  After little promotion of the change by both the government and broadcasters, Congress is now scared about consumers complaining about their TV's going dark:

http://www.betanews.com/article/Congress_Expresses_Concern_Over_Digital_TV_Switch/1185551205

As far as the auctioning off of spectrum, this may hurt your over the air reception as the tuners are not very selective:

http://www.tvtechnology.com/pages/s.0072/t.7434.html

Being a broadcaster I just want to get it over with. NTSC is nice but it is hard for broadcasters to be spending money in electricity to keep two transmitters going now (not to mention two types of in-plant signal distribution).

another couple of web sites:

http://www.atsc.org/
(standards committee for DTV)

http://www.avsforum.com/
(a very good site for consumer questions and such, much like amfone).

A pet peeve of mine is HD radio. The Ibiquity people made the poor choice to call IBOC (In-Band-On-Channel) digital radio "HD", stealing the promotional idea from HDTV. This radio stream is actually a much lower bit rate reduced and compressed signal than a CD. And it sounds it.

73,
Dan
W1DAN

[Pete, WA2CWA]

Hi Bob,

Have spent very little time looking into HDTV,  was in market for new LCD TV,  for remote off-grid QTH,  so was just down to which one and what features.

Just Googled "set top hdtv converter"  and got hits from Circuit City,  Target etc.  Some of the results were were for "set top hdtv receiver"  You might try searching again ... things are changinr quickly.

Think that if you could go to Best Buy,  CC and WallyMart you might find one that you could try,  and "if not delighted,  you could return for cheerful refund" ...  mabe those days are gone.  Just make sure that you could return the item.  You might need an outdoor HDTV antenna if U are inna fringe area.

HDTV is coming,  and the price curve has come down in the past year.

GL  Vic  K6IC

I thought the whole point of the "coming" of the setop converter box was to allow the digital off-the-air reception to be converted to analog signals for that your old analog TV will work after Feb. 2009.
Given that's the case, why would you need to go out now and buy one for your analog TV?

For the last several years you have been able to buy a TV that is "HD" capable(extra equipment required). For these TV's, my understanding is that an "HDTV front-end box" was an external add-on. It looks like today, most manufacturers are providing TV's that are "HD ready-to-go". My cable provider indicated to me that when we get a high definition TV to come in and exchange the present cable converter box for one that will decode the current and future HD cable channels.

[K6IC]

We,, Pete,

I was trying to post a reply to Bob,  regarding his post which went something like this ..

"About six months ago I did a search trying to find one of these digital converter set top boxes since WTAE in Pittsburgh supposedly is broadcasting in both digital and analog.  Found a model for Radio Shack but it was already discontinued, then Walmart had one that was also discontinued.  So who is selling this miracle set top box that the government will have a rebate for?  I still want one CHEAP!  I have a hunch that I'm located just far enough away that it won't work for me.

Bob  "

It was exclusively trying to reply to Bob's desire to find  a set top box.

And as you correctly observed,  it has NOTHING to do with my LCD HDTV.

I realized at the time of my LCD TV post that I was kinna hijacking this thread ... so I apologize for that,  but it did relate in a certain way.

My previous post on set top converter should have said that,  "Just NOW, not a minute ago, I did a Google search for  "set top hdtv converter"  just to see what is available right NOW, regarding your interest in a set top hdtv converter,  and there were hits from CC, Target ...   "     and so on .. etc.

Sometimes in the interest of brevity,  will leave out a lot of the intermediate steps in getting point A to D.

Sooo  SRI for the confusion.    Vic  K6IC

73  Vic  K6IC

[Pete, WA2CWA]

We,, Pete,

I was trying to post a reply to Bob,  regarding his post which went something like this ..

"About six months ago I did a search trying to find one of these digital converter set top boxes since WTAE in Pittsburgh supposedly is broadcasting in both digital and analog.  Found a model for Radio Shack but it was already discontinued, then Walmart had one that was also discontinued. So  who is selling this miracle set top box that the government will have a rebate for?  I still want one CHEAP!  I have a hunch that I'm located just far enough away that it won't work for me.

Bob  "

It was exclusively trying to reply to Bob's desire to find  a set top box.

And as you correctly observed,  it has NOTHING to do with my LCD HDTV.

I realized at the time of my LCD TV post that I was kinna hijacking this thread ... so I apologize for that,  but it did relate in a certain way.

My previous post on set top converter should have said that,  "Just NOW, not a minute ago, I did a Google search for  "set top hdtv converter"  just to see what is available right NOW, regarding your interest in a set top hdtv converter,  and there were hits from CC, Target ...   "     and so on .. etc.

Sometimes in the interest of brevity,  will leave out a lot of the intermediate steps in getting point A to D.

Sooo  SRI for the confusion.    Vic  K6IC

73  Vic  K6IC

Not to beat this to death, but Bob, in his post, made no mention of hdtv converter. And, you said above, "regarding your interest in a set top hdtv converter" And, from his post, "So  who is selling this miracle set top box that the government will have a rebate for?"

My point is that the box that you can derive a rebate from is the "box" that allows analog TV's to receive off-the-air digital TV transmissions after Feb. 2009. I believe I read on the dtv.gov web site that the analog quality would be a tad better but not equal to the quality if you were watching it on a digital set.

And, from the dtv.gov site:
* Consumers will always be able to connect an inexpensive receiver, a digital to analog converter box, to their existing analog TV to decode DTV broadcast signals.

* Digital to analog converter boxes will not convert your analog TV to high-definition.