need help with reception
 

hi all,

i'm trying to figure out why i get great reception for some channels but not others. my radar plot is here: http://www.tvfool.com/?option=com_wr...073b9ed2be318a and also attached.

in particular, i'm frustrated with the poor reception i get for the various KQED channels - 9.1, 9.3, and KQEH 54.3. i'm especially confused since KQED is listed as being of comparable strength and in the same location, as other channels for which i get excellent reception. KGO, 7.1 and 7.2 come in really well, and consistently. but my reception for KQED channels seems to vary, with no obvious pattern. sometimes it comes in really well, sometimes it doesn't. 9.1 seems to come well more often than 9.3, but not often enough to be reliable. 54.3 which rarely comes in at all (but i see that its transmitter is in a different direction/location).

do channels with the same whole number use the same transmitter - is that why for example, 9.3 isn't listed separately? i would also like to get 32.4, one of the KMTP channels.

i live in a wood construction apartment building, on the top (third) floor. one thing is that i do have my TV, and antenna, somewhat in the interior of my apartment. to have the antenna near a window would require probably ~30 feet of cable, and spanning across multiple doorways (argh). but also, i did have it set up near the window at one time, and it didn't seem to make too much of a difference (my window faces southeast, while ).

i'm currently using a mohu leaf. i'm not sure if it was a smart change, because while for some channels i have improved reception (KNTV 11.1 and 11.2 i think), other channels stopped coming in completely (eg KOFY 20.1 ). before, i was using the philips SDV2710/27: http://www.p4c.philips.com/cgi-bin/d...ctn=SDV2710/27, which at least i could move around/turn more (while the mohu has to stay on my wall). any advice re: which one is better would be helpful too.

ALL Questions and Answers and Information - Broadcast Tv Reception and More
 

Do you have a balcony to the , south/east , south , south/west??

3 floors , lets say 10 feet per floor , that 30 feet.

Make a tvfool radar report plot with a antenna at 30 feet.

hi electron,

unfortunately, no balcony. the only exposures my unit has are to the southeast (two large windows).

re: antenna height - my ceiling heights are 8'. with two units below, and the antenna sitting either next to the TV or on the wall behind it, about 4' up, that's 8 + 8 + 4 = 20'. floor-to-floor is probably 9', so i think my antenna is probably no more than about 25' up. having said that, i've attached the radar plots for 30' (i could possibly reach 30' if i attached the mohu to the highest point on my wall) and 40' too, since you asked. :-)

ALL Questions and Answers and Information - Broadcast Tv Reception and More
 

Most of the Tv stations are to the south/east and south/west.

For a indoor antenna I recommend a Terk HDTVi antenna aimed at about 180 degree magnetic compass , in between the 2 groups of Tv stations to the south/east and south/west so as to receive the 2 groups of Tv stations.

Here is how to aim indoor antenna , http://www.kyes.com/antenna/pointing/pointing.html.

Best place for reception Will Be a south wall or a wall that is close to something like a south wall or window.

As to the multipul door ways , well.

There are rubber strips that go on the floor of door ways , the rubber strips have a channel through them so that extension cords , phone cords , coax cable can be passed across the door way.

Also do the buildings have satellite dishes outside??

Here is a Tv Antenna that looks like a small dish , On Purpose.

http://www.antennacraft.net/Manuals/HDX1000_manual.pdf.

If the HDX1000 is outside aim the HDX1000 at about 180 degree magnetic compass.

Here is how to aim outdoor type antennas , http://www.kyes.com/antenna/pointing/pointing.html.

Here are places to buy antennas and etc. , http://www.solidsignal.com , http://www.antennacraft.net , http://www.amazon.com.

ALL Questions and Answers and Information - Broadcast Tv Reception and More
 

Digital Broadcast Television can transmit more then one channel , in a channel.

As an example , lets say channel 15 , in the frequency range that is channel 15 , digital Tv can put , 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , Tv channels in the same frequency range/space that only one Analog channel would fit into.

Stuffing , 5 , 6 , 7 , 8 , digital sub channels in to the frequency range/space that made up a single Analog channel of the past means the digital pictures is not as clear as , 1 , 2 , 3 , 4 digital channels.

Odd or even numbers have nothing to do with the actual transmission or reception.

The actual digital sub channels are digital bit streams , the numbers are away of identifying the digital bit stream ( picture and sound) that you the viewer are watching.

As an example.

Real digital Channel 15 can be one digital Tv channel , 15.1 .
Or 15.2 = 2 digital Tv channels
Or 15.3 = 3 digital Tv channels
Or 15.4 = 4 digital Tv channels
and etc. .

As an example.

Real digital Channel 10 can be one digital Tv channel , 10.1 .
Or 10.2 = 2 digital Tv channels
Or 10.3 = 3 digital Tv channels
Or 10.4 = 4 digital Tv channels
and etc. .

ALL Questions and Answers and Information - Broadcast Tv Reception and More
 

It is best to make a live tvfool radar report plot like you did at first.

The attached images (pictures of the report) are dead , cant do any thing with them.

The answer to your question is "not necessarily." Virtual channel numbers can be used in a number of ways. The most popular use of virtual channel numbers is to display the station's historic channel number. Many broadcasters use a primary transmitter and one or more translators to transmit their programming. All viewers see the same virtual channel number irrespective of the actual signal that they receive. Two stations in the Washington, DC area use virtual channel numbers for a novel purpose. WNVC (RF24) and WNVT (RF30) have a joint affiliation with the MHz Networks. The MHz Networks specialize in delivering international broadcasts to viewers in the US. WNVC (RF24) broadcasts five MHz Networks program feeds as 30.1, 30.2, 30.3, 30.4, and 30.5. WNVT (RF30) broadcasts an additional five MHz program feeds as 30.6, 30.7, 30.8, 30.9, and 30.10. To the viewer, these two stations appear to be a single station that broadcasts 10 program feeds.

ALL Questions and Answers and Information - Broadcast Tv Reception and More
 

Thats some interesting information about the multipul use of digital sub channels.

And I like the word , historic , I have been using the word legacy.

Thanks , MisterMe.

radar plots
 

hi all,

didn't realize i wouldn't get emails for your followup msgs - hence my delay. thanks for all the info!

here's the radar plot for 30': http://www.tvfool.com/?option=com_wr...1349986dfd8f95
and 40', though i think it's not applicable to me: http://www.tvfool.com/?option=com_wr...1349351d7f4262

btw, i compared these side by side, also to my original 20' plot, and the differences seemed to me to be small - but are they still significant?

if i understand what y'all are saying about the virtual channel numbers, it means that for example, 9.1, 9.2, and 9.3 could be being transmitted from different transmitters. if that's the case, then why aren't they included separately in the radar plots? oh, and i realized it's KQED digital 9.2 that i am having trouble with, rather than 9.3. but then, neither shows up in the radar plots.

Because the TVFool tools are concerned with the signal propagation forecasting. It is not intended to get into the payload of those signals (much). That information is available elsewhere, notably at rabbitears.info.


Please note that for stations who held an analog TV license, their virtual channel assignment is that original analog channel number with a .1 or -1 suffix (with only minor exceptions).

While this scenario is theoretically possible, I am aware of no broadcaster that does this. The MHz Networks case is done that way because each 6 MHz ATSC broadcast channel has only enough bandwidth for 5 standard definition program feeds. What is becoming popular is single ownership/operation of multiple network affiliates. In my local area, the NBC and FOX affiliates operate out of the same studios by the same personnel. However, the two stations have different owners, but one station's owner contracted-out the operations to the other. Our ABC and CBS stations have the same owner. Each of these four stations operate on different RF channels.

No, only one transmitter is used to broadcast a group of virtual channels. A given broadcast commonly has from 1 to 5 virtual channels imbedded in the data stream, but in theory, there can be even more virtual channels carried by a "REAL" channel.

If you have cable or DSL internet service, you already use the concept of virtual channels. You have one "REAL" internet connection, but it can serve several computers, each with several web browsers active at the same time. The television station is able to send more than one data stream (representing video/audio or even data) in the available bandwidth of their "REAL" channel.

Again, as has already been said, TV Fool's purpose is primarily aimed at helping you receive the "REAL" signal regardless of how many data streams (virtual channels) are encoded by the broadcaster.

As you look at your TV Fool report, focus on the "real" channel number, it represents a real transmitter. It also guides you in selecting the correct antenna because the antenna has no awareness of virtual channel numbers nor any sensitivity to modulation type (analog or digital). Antennas are designed and built with a real range of frequencies in mind. There are three separate ranges in use here in North America, Low-VHF (real CH-2 through 6), High-VHF (real CH-7 through 13) and UHF (real CH-14 and higher).