Nashville, TN - OTA - Page 6

Is the Nascar race in 480p widescreen? It looks like it....not HD sharp.

No Fox17 HD here all day.


Patrick

Whats up with CBS today? I think the Titans game was broadcast in HD, but OTA channel 5 broadcast the regular feed. Now, COLD CASE is in standard 4:3 , although it "started" out in HD, then switched to regular, with a nice caption to tease me saying "simulcast in HD". What are the people at the local CBS affiliate screwing around with?

Seems like all of out locals dropped the ball today. No NFL, I had to call in the race, and it looks like some pt programming is messed up. Hopefully just one bad day.

Jerry

Do we have direct numbers to report problems like that to the engineers?

The Titans game was never scheduled to be in HD. You can find this info at http://cbs.sportsline.com/cbssports/schedules/page/nfl

I don't know about Cold Case. Was it a rerun or a new episode? Sometimes CBS doesn't do HD for reruns.

Season premiere of cold case. Also, the Sunday night movie on right now says it is available in HD, just like cold case, but it isnt.

Thanks for the link.

The phone book suggests you might reach them at 244-1717.

Bellevue black hole followup:

Switched to the CM4228 and now I get 58-1 (UHF 23, I think) like it's right next door...

but, still not a sniff of 17-1 (UHF 15).

Oddly, both transmitters and antennas are on the same stick NNW of downtown. Go figure.

Splicer issues must be the problem on Fox since no HD at all on Sunday.
Can anyone get Dexter King and see what's up?

He was working second shift last week.

I've got a call in for him on another matter.

So let me get this straight....you are getting the WNAB-DT (WB) in Bellevue despite its low power. But you're not getting WZTV-DT (FOX) or WTVF-DT (CBS)???

Ding. Ding. Ding. Ding.

We have a winner!

Looks like Fox 17 splicer is back on line,if that's what the problem was.
Picture seems much crisper today and doesn't have that washed out muted look.
Anyone know?

Well I know I'm preachin' to the choir, but you and I know that this makes no sense. CBS, FOX, WB and UPN are all in the same part of town and literally on the same vector from Bellevue (in my case, at 29 degrees). CBS and FOX are pumping at full strength but only the WB comes in strong which is running hamster power?

I'd love someone who knows a thing of two about TV transmissions explain that one...

Me too. I spent a half hour on the phone today with a WTVF engineer. His only thought was that the lower WNAB-DT channel frequency (23) is somehow able to penetrate whatever is blocking me. That makes no sense, however, since WZTV-DT is on channel 15...even lower...and I can't get that. WTVF-DT is at roughly half their authorized power of 1 megawatt because they will have to move from channel 56 some time in the future and they can save some money pre move.

Jon, have you tried analog UHF 17 (regular WZTV)? Might be interesting to compare.

I don't understand you not getting *any* signal at all on 17-1. What does your HD receiver's signal strength indicator say?

I know this sounds absurd, but does your HD receiver have a "channels I receive" configuration? Is it possible it scanned for 17-1, didn't find it (maybe was momentarily down), and flagged 17-1 as inactive?

If you get any signal strength on HD or any analog signal on UHF 17, you could turn the antenna while someone watches the signal.

Another possibility is some kind of multipath cancellation. While the 4228 has good gain, it has a fairly wide beamwidth, so in theory multipath could affect it. There are very directional UHF yagis which might work. See http://www.antennasdirect.com/LongRangeAntennas.htm.

Would also be interesting to compare your elevation to that of the WZTV-DT antenna. There are USGS topo maps at www.topozone.com you can use to estimate your elevation, or use a GPS. Along the bearing from your location to the WZTV-DT antenna, are there any topographical obstructions obvious on a USGS map?

Analog 17 is still on the WSMV tower on Knob road.


I have the newest Hughes integrated DirecTV receiver. The newest firmware added a signal strength meter and the receiver recognizes a tiny amount of signal (poor on the meter) for 30-1, 17-1, 5-1 and 5-2.

I have both a directional yagi and the 4228 up at present. The yagi sees very little on 58-1, not enough for a lock, and nothing on the other stations from that area.

Virtually every hill in Davidson county is between me and the 3 Sinclair stations (which are on the same antenna tower) and WTVF-DT.

The whole thing is making my head hurt.

Site is Chapmansboro TN which is 23 to 33 miles from the applicable towers in Nashville TN. Transmitters at or between 125 and 151 degrees from my house or a 26 degree spread.

Can pick up all stations except WB (23), UPN (21) and PBS (46) (PBS is still testing and I may not even have looked for them at the right time). I think these stations are probably out until they increase their power.

Primary purpose is to improve signal on ABC (27) NBC (10 - VHF), CBS (56), and FOX (15) and be ready to receive WB, UPN and PBS when power is increased (if I could pick up the low power WB, UPN and PBS that would be great). Currently in order to receive frequencies from both 125 and 151 degrees I must compromise in pointing the antenna which decreases the strength of some signals. These signals are mostly in the 60's (per the HR10-250) so they are not great. Ideally I would like for my UHF antenna to pick up the NBC VHF station. Worst case I will add a separate VHF only antenna.

Antenna is on a mast on the side of a two story house with large trees that are 30 feet above the antenna in direction of transmitters. There are some hills between my location and Nashville but nothing very near my house.

Currently I have a large Radio Shack combination VHF/UHF antenna which is about 6 years old (don't know the model # but I think it was the biggest they had at the time). Back in the day, analog reception was OK but not great. DirecTIVO HD tuner (HR10-250). Rotor is a no go because of TIVO.

I have a cable run of 100 feet from the Antenna to a Terk58 (5X8) powered multi-switch and then another cable run of 100 feet from the multi-switch to the HR10-250 where the signal is diplexed out.

I am primarily considering the 91XG or the DB8. I realize they may be overkill based on my range to the towers but they will hopefully help out with the tree issue? Is the 91XG too directional for the 26 degree spread I have?

If the DB4 or other smaller antenna would work (or be better) that would be fine. However I want to minimize my trips to the roof (actually 3 stories where the antenna is located due to a sloping lot) more that I want to minimize the cash outlay.

How concerned do I need to be with wind load with any of these antennas compared to the large Radio Shack unit? Mast location is not ideal as it is not at the highpoint of the roof (I however don't want to move it). The antenna is about 5 foot above the roof where it is mounted and probably 2 to 3 feet above the highpoint of the roof. No guy wires.

Based on my distance from the transmitter it appears I don't need a preamplifier but I didn't know if the relatively lengthy cable runs may make the Ch Master 7777 a beneficial add?

OK, if you've actually read his far what antenna gives me my best shot at success?

Thanks in advance for your thoughts.

I'm curious if you have eliminated a rotor because your TiVo can't automatically control its direction when recording a particular OTA channel.

One additional thought, I've got a UHF only 8-bay bowtie antenna up right now and it receives WSMV-DT perfectly. You may not need a V/U combo at all.

Your correct the TIVO cannot change the direction of the antenna through the rotor. I have never heard of any device like a VCR or DVR that could do this unless I'm just out of the loop.

I had orginally posted this question as a separate thread titled "Best Antenna for this Scenario?" I'm somewhat surprised the Moderators moved it into the Nashville thread as it seems to me this is a fairly generic question regarding distances, trees and best antennas. It really limits the viewing/participation when discussions occur only in the city threads.

I have the 91XG and it is a great antenna for UHF. It does not pick up Channel 10 for me. I have a seperate VHF antenna for that. I also have a Winegard 8200 pre-amp which helps things considerably. BTW, 26 degrees should be fine for the 91XG.

Jon, I might have a theory of what's going on. First, all the stations on the north side of town are very weak coming through the hills of West Nashville as we all know. I decided to review http://www.hdtvprimer.com and specifically reread the section on antenna and measuring gain.

Here's the chart I'm referring to:

http://www.hdtvprimer.com/ANTENNAS/types.html

The UHF channels we're trying to receive are 15 (FOX), 21 (UPN), 23 (WB) and 56 (CBS). In addition, VHF channel 10 (NBC) is on the same vector, although far closer in location. The diagrams on hdtvprimer.com show the gain charts for the ChannelMaster 4228 8-bay antenna that you are using and a ChannelMaster 4248 Yagi, which isn't the Yagi you have but close enough for the sake of argument. When properly pointed, you are trying to get the most gain out of a signal and hopefully avoid nulls if the antenna isn't pointed directly at the tower. Since all signals are on or close to the same vector, let's assume you have the antenna properly pointed. Pointing directly at the target is critical since being off by 15 degrees results in a -5 db drop with the Yagi and -16 db drop at 20 degrees. The 4228 is a bit more friendly but at 25 degrees off target, it plunges to -20 db loss heading for a null at 30 degrees.

What the chart shows is interesting. The 4248 yagi is biased for the least amount of gain loss in the higher channels. Channel 60 sees 0 gain loss which would mean that if all things being equal, it would have the greatest chance of bringing in Channel 56 of the available channels. Indeed, your Yagi does see a weak signal on that channel and you might see better if CBS was running at full power, which it isn't. However, the 4248 starts becoming less effective in the lower channels. Channel 50 sees about a -2 db loss and all other channels are seeing a -3 db loss. That may not sound like much, but gain is a logarithmic measurement for decibels. So decibels of gain looks like this:

20 dB = gain factor of 100
10 db - gain factor of 10
3 db = gain factor of 2
0 db = no gain or loss
-1 db = 20% loss of signal
-3 db = 50% loss of signal
-10 db = 90% loss of signal

At the same time, the signal has to overcome whatever noise it encounters (signal/noise ratio) which could be anywhere from atmospheric noise to noise in the antenna cable or other attached devices.

This preceding data comes from the following page on hdtvprimer.com:

http://www.hdtvprimer.com/ANTENNAS/basics.html

The 4228 8-bay antenna is a little different but again does not have the same ability to pull in a signal over the entire frequency range. Best is channel 50 and then other channels between 30-50 give up about a -1 db....again, not a lot unless you are dealing with weak signals. But like the 4248 Yagi, the worst performance is in the lowest channels. Channel 20 gives up -3 dbs (50% loss). Again, great performance overall for an antenna, but we're dealing with very weak signals.

So it's possible that your Yagi's ability to at least partially display channel 56 is born out by the data while other lower channels would not. That leaves the next possible problem....signal loss in the cable from the antenna to the receiver. Given that the signals are so weak in the first place, even if the antenna got a servicable signal, it signal strength might drop beneath the noise level by the time it gets to the receiver. According to hdtvprimer.com, RG-6 cable loses 1 db of signal every 15 feet for channel 52. So on their chart, a 100 ft cable run could result in as much as a -6 db loss in the upper channels like 56. This is one case where the lower channels have an advantage of less gain loss over distance, at -5 db of loss for channel 20 at 100 ft of RG-6 cable, you may still be SOL.

An antenna amplifier could improve the signal enough on the route to your receiver to make a critical difference (if you're not using one already). Most of the time you wouldn't need one in the city limits (as someone else in these pages pointed out) but in this case it could be crucial. A Channelmaster 7775 or 7777 can provide up to 26 dbs of gain on the way from the antenna to the receiver depending on the channel, cable used and the distance. These amps are also known for their very low noise (about 2 dbs), hence a great signal to noise ratio.

Anyone who knows more about this than I do, please correct me if anything above is wrong (since I'm clearly not an expert...I'm just reading a web site). But if what I read is true, then there may be more than can be accomplished in order to crack this problem. It's also possible that a highly directional Yagi meant for extreme distances could be helpful in our situation, especially since all the problem child signals are in one direction only. In your case Jon, that would leave the 4228 to pick up whatever's left in other directions.

Lastly, I'm curious as to what antennaweb.org said about the type of antenna you would need from your specific address. Since their database now corrects for terrain, after their web site upgrade in Jan 2004 all of the stations in North nashville disappeared from my list of possible stations. Since I have a hill right in front of me and lots of trees, this isn't surprising. But I wonder if your address even finds the north Nashville stations in their database.

You've done yeoman research. Thanks. Adding to the confusion is this quote from your research:


No relief for my headache.

I had a similiar problem as this one, but this is what I did.

I went to sears and picked up a sirt ota receiver to verify that it was on the transmission and not the cable/antenna/hd receiver. Used a visa so i could return it after using it.

What I found out was my receiver was bad. The sirt picked everything up that I was missing very strong. At least this would help you eliminate the receiver as the culprit. Stranger things have been known to happen.....

patrick

Given your cable run, I'd definitely suggest the 7777 preamp. However it appears you're diplexing your OTA signal onto your satellite feeds, so not sure how a preamp works in that case. Usually you get best results with a non-diplexed dedicated line from your OTA antenna.

Re antenna, if in doubt I like the 4228 (or Antennas Direct DB8). They're physically compact and not very expensive. It's likely all you need for UHF HD locals, plus WSMV-DT which is VHF high band. I'm 20 mi S of Nashville and get all UHF HD locals plus WMSV-DT with the Channel Master 4221 inside my attic. That's 1/2 the size of the 4228, plus I probably lose 20-50% signal inside the attic. I use a Channel Master Spartan preamp, which isn't as good as the 7777.

I know it sounds like a lot of work to do a separate dedicated cable run for your UHF antenna, but you just do it once. Your old RS antenna probably needs some maintenance anyway. Best to minimize trips and just do it all at one time -- new cable, new antenna, model 7777 preamp. A new antenna will last quite a while. Hopefully we'll have HD locals via satellite by the time it wears out. Thank goodness you don't need an antenna rotor.

There should be no confusion. Part of the reason why the 4228 is so popular is that it's a great antenna and is relatively easy to get good results under normal circumstances.

1. It does have high gain.
2. Its gain is more evenly distributed versus the Yagi 4248 according to hdtvprimer.com. Similar results probably exist with other Yagis.
3. The nulls can eliminate multipath quite effectively (Yagis don't have nulls by design).
4. You can stack them for 16 or 32 bay designs (this has some practical drawbacks).

But your Yagi was the one that picks up channel 56 (CBS) intermittedly since even though its gain isn't evenly distributed. Since it gets maximum gain in the upper channels, it makes sense that you would see what you observed.

I'd go back to Randolf and Rice and get a Channelmaster amp and see what happens. You just might be able to break through the signal to noise barrier for a clean signal.

Again last evening 58-1 (23) was booming in. Unfortunately, there's not one program on that station I'd even consider watching.

That tells me that it is possible to get the lower stations in at least part of Bellevue if they operate at full power. If they don't then fighting to get a lock is a big problem. There may be hope yet assuming these guys ever go fill power all the time like the FCC mandates, but I imagine that WTVF may never go full power as long as they are sitting at Channel 56.

The situation is getting even spookier, but I may have found some answers.

Today, the digital signals for 17, 30 and 58 are booming in...eureka! Still a tiny, unlockable signal from WTVF.

Yesterday, a neighbor took down a big tree that was in the way and this has evidently helped tremendously. But, still nothing on 56 and this confuses me and the assistant chief engineer at WTVF who is an old friend and just spent a few minutes offering ideas, but really nothing seems to make sense. He confirmed they are at 400kw and will probably be there for a while.

BTW, the Fox digital signals on 17-1 and 17-2 are gorgeous.