• Get involved.
    We want your input!
    Apply for Membership and join the conversations about everything related to broadcasting.

    After we receive your registration, a moderator will review it. After your registration is approved, you will be permitted to post.
    If you use a disposable or false email address, your registration will be rejected.

    After your membership is approved, please take a minute to tell us a little bit about yourself.
    https://www.radiodiscussions.com/forums/introduce-yourself.1088/

    Thanks in advance and have fun!
    RadioDiscussions Administrators

Digital TV newbie - lots of questions!

I just bought a new TV. It's a "SDTV", which means that it can pick up digital channels and display them in standard resolution. This is my first experience with digital TV, so please bear with me as I provide some basic info and ask some basic questions.

I hooked up a cheap Philips-Magnavox set-top antenna, just to see what would happen. I wasn't expecting to be able to receive any channels, but to my amazement, the "auto program" feature picked up the following (I'm labeling these exactly the way they show up on-screen) --

3.1 KTVK-DT
5.1 KPHO HD
8.1 KAET-HD
8.2 KAET-SD
8.3 KBAQ-FM
10.1 KSAZ DT
12.1 KPNX-DT
12.2 Weather
15.1 KNXV-HD
15.2 KNXV-DT
33.1 KTVW DT
33.2 KFPH CA
45.1 KUTP DT
51.1 i
51.2 Pax
51.3 Worship
51.4 FaithTV

Questions:

* All of these channels' call letters are just the analog call letters with a "-DT" and the dial position, right? So for example, "KPHO HD" is really "KPHO-DT 5.1"..."KBAQ-FM" is really "KAET-DT 8.3", correct?

* In the case of 5.1, 8.1, and 15.1, this is just the HD signal being broadcast over a digital channel, right? Are there any on my list that are not labeled as HD, but actually are HD signals?

* Is there a good, up-to-date list of digital and HDTV channels available in the market? The best one I've been able to find is @ http://www.oldradio.com/archives/stations/phx.htm

* EDIT: Found another list @ http://www.hdtvmagazine.com/programming/broadcast-market.php?dma_name[]=Phoenix%20(Prescott)

* On http://www.oldradio.com/archives/stations/phx.htm - it says, for example, that KPHO-DT is channel 17. If that's the case, then why am I picking up KPHO-DT on 5.1? Or why is KPNX-DT shown as channel 36 on that page, yet receivable as 12.1 on my TV?

* The picture size that the TV defaults to varies depending on the channel:

"Black bars" across top and bottom of screen

5.1
8.1
10.1
12.1
45.1
51.1
51.3

"Black bars" around all four sides of the screen

3.1
15.1
45.1

Full screen

8.2
8.3
12.2
15.2
33.1
33.2
51.2
51.4

I can't really seem to find a pattern. Can someone explain these picture size variances?

EDIT:

I was able to get the resolution and aspect ratio (I think those are the terms?) for each channel to be displayed on-screen: (Will this change depending on the program?) --

720p 16:9

3.1
10.1
15.1

1080i 16:9

5.1
8.1
12.1
45.1

480i 4:3

8.2
8.3
12.2
15.2
33.1
33.2
51.1
51.2
51.3
51.4

The two lists still do not match - for example, 10.1 has black bars across only the top & bottom and is 720p 16:9...15.1 has black bars on all four sides yet is also 720p 16:9...45.1 has black bars on all four sides but is 1080i 16:9.

And what exactly do "480i", "720p", and "1080i" mean?

* The picture quality of a "DT" channel is supposed to be better than the analog version of that channel, but not as good as the "HD" channel, right?

* How much should I expect to spend on for an indoor antenna that can reliably pick up as many digital channels as possible? 15.1, 15.2, 33.1, and 33.2 have been hit-or-miss...they were receivable when I first hooked up the TV on Monday, but they disappeared after that - today is the first time since Monday that I've received a signal.
 
> Questions:
>
> * All of these channels' call letters are just the analog
> call letters with a "-DT" and the dial position, right? So
> for example, "KPHO HD" is really "KPHO-DT 5.1"..."KBAQ-FM"
> is really "KAET-DT 8.3", correct?

This is part of the Program and System Information Protocol (PSIP) system that is a standard for United States DTV. The station can put a description in there that doesn't have to be the real "call sign" (which would be "KPHO-DT 5.1" or "KAET-DT 8.3"

> * In the case of 5.1, 8.1, and 15.1, this is just the HD
> signal being broadcast over a digital channel, right? Are
> there any on my list that are not labeled as HD, but
> actually are HD signals?

These are the actual channels that the stations send its HDTV programming over. For example, KNXV multicasts its HDTV programming on 15.1 and SDTV on 15.2.

>
> * On http://www.oldradio.com/archives/stations/phx.htm - it
> says, for example, that KPHO-DT is channel 17. If that's
> the case, then why am I picking up KPHO-DT on 5.1? Or why is
> KPNX-DT shown as channel 36 on that page, yet receivable as
> 12.1 on my TV?

This is also a feature of PSIP. In order to avoid viewer confusion, the TV station "re-maps" its DTV signal that broadcasts on a UHF frequency to its "mother" station (for example, once your TV picks up KPHO-DT on UHF 17, it will automatically re-map the station as "5.1"). This will continue once the analog-to-digital transition is complete (i.e.: KTVK and KPHO will broadcast on 24 and 17, respectively, but their "technical" channel numbers will still be 3.1 and 5.1.). Here is a description of PSIP (pops)

> The two lists still do not match - for example, 10.1 has
> black bars across only the top & bottom and is 720p
> 16:9...15.1 has black bars on all four sides yet is also
> 720p 16:9...45.1 has black bars on all four sides but is
> 1080i 16:9.
>
> And what exactly do "480i", "720p", and "1080i" mean?

480i definition (pops)
720p definition (pops)
1080i definition (pops)

>
> * The picture quality of a "DT" channel is supposed to be
> better than the analog version of that channel, but not as
> good as the "HD" channel, right?

Not exactly. Most of the time it depends on the bandwidth that is available (the more multicast channels that are transmitted on a signal, the more picture degradation you will see) and the compression scheme (or bit rate) the station uses for each of its channels.

>
> * How much should I expect to spend on for an indoor antenna
> that can reliably pick up as many digital channels as
> possible? 15.1, 15.2, 33.1, and 33.2 have been
> hit-or-miss...they were receivable when I first hooked up
> the TV on Monday, but they disappeared after that - today is
> the first time since Monday that I've received a signal.

While you can still use a standard UHF "bow-tie" or "loop" for DTV, it's not going to give you the best results. Many DTV owners have had great success with the design of the Zenith (or Philips) "Silver Sensor" or Terk "HDTVi" antennas (the HDTVi might me more readily available). These antennas however, are very directional (and larger than the standard antenna), and they should be pointed in the direction of South Mountain. As for any over-the-air television broadcasts, an outdoor antenna works best (and from your location, you may be able to receive some Tucson stations as well).
 
>
> While you can still use a standard UHF "bow-tie" or "loop"
> for DTV, it's not going to give you the best results. Many
> DTV owners have had great success with the design of the
> Zenith (or Philips) "Silver Sensor" or Terk "HDTVi" antennas
> (the HDTVi might me more readily available). These antennas
> however, are very directional (and larger than the standard
> antenna), and they should be pointed in the direction of
> South Mountain. As for any over-the-air television
> broadcasts, an outdoor antenna works best (and from your
> location, you may be able to receive some Tucson stations as
> well).
>

I have the "luxury" of using an old school outdoor antenna, and at my house in Central Scottsdale I am able to pick up KMSB and KTTU out of Tucson. They're essentially a waste since I can get all of the same programming on Phoenix channels, but I'm impressed I'm able to get them so clearly. Why can't I get KVOA, KGUN and/or KOLD as well? Don't they all broadcast from Mt. Lemmon?
 
> I have the "luxury" of using an old school outdoor antenna,
> and at my house in Central Scottsdale I am able to pick up
> KMSB and KTTU out of Tucson. They're essentially a waste
> since I can get all of the same programming on Phoenix
> channels, but I'm impressed I'm able to get them so clearly.
> Why can't I get KVOA, KGUN and/or KOLD as well? Don't they
> all broadcast from Mt. Lemmon?
>

Not all, but the major ones do (NBC, ABC, CBS, Fox, PBS, Univision, UPN). KWBA (WB) broadcasts from the Santa Rita Mtns. about 35-40 mi. SE of Tucson since their COL is actually Sierra Vista. KHRR (Telemundo) broadcasts from Tower Mtn. to the W of downtown.

I'm not surpised that you get KMSB and KTTU. Their signals are among the strongest, at 480 kW each. Do you get KUAT 6/DT30? Their signal is 667.5 kW.

KGUN is licensed for 266.3 kW and KOLD for 108 kW. Those signals probably don't reach. KVOA (NBC), KUVE (Uni) and KHRR (Tmd) are all operating at lower power via STA so they don't reach either.<P ID="signature">______________
Dave</P>
 
Status
This thread has been closed due to inactivity. You can create a new thread to discuss this topic.


Back
Top Bottom