Repack signal quality

andy_horton

andy_horton

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WDSI CHATTANOOGA TN moved midnight Sept 1st. Physical channel 40 went dark at 11:58pm, I rescanned and it has moved to physical channel 14. However, the signal quality jumped immediately from 74-78% with pixelation to 93% steady. Obviously night seems better reception, but that's a huge increase. Would this huge frequency change (channel 14 from 40) using my strictly 4 bay UHF only with preamp pick up physical 14 any better than 40? Or maybe a power adjustment? Or maybe just luck of the draw nighttime fluctuation? Thanks
 
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Trip

Trip

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Being lower in frequency, 14 will bend around terrain better than 40. Additionally, the station spent extra money to increase power from 84 kW to 120 kW, and spent the money to put up an antenna with vertical polarization as well as horizontal--about 38 kW worth in the vertical plane. If you were getting a polarity shift due to the terrain, that vertical power could help a lot.

- Trip
 
andy_horton

andy_horton

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Being lower in frequency, 14 will bend around terrain better than 40. Additionally, the station spent extra money to increase power from 84 kW to 120 kW, and spent the money to put up an antenna with vertical polarization as well as horizontal--about 38 kW worth in the vertical plane. If you were getting a polarity shift due to the terrain, that vertical power could help a lot.

- Trip
Thanks, Trip. I figured since the signal after 3 days now is steady 94-95% vs losing it during the day usually, and eventually hopefully the other repack channels will improve. Everything now, still with all foilage and metal roofs around, and hills, blah blah etc I'm very impressed and am wondering what their plans are for the future as far as either additional subchannel OR 3.0...believe it or not, Chattanooga TN market is becoming quickly saturated with subchannels for just a medium market. When I look at general power output and signal patterns, it's not uniform like a circle from rhe transmitters most grouped within 3° on Signal Mtn TN because of a mountain blocking cochannel interference to Nashville, and obviously we can't infringe on Knoxville DMA or ATL DMA. Although extreme fringe there is some crossover from what I understand from the Knoxville market with Chattanooga. Just the way the terrain is
 
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Nobody seems to believe me when I say that the repack will improve the signals of many of the remaining stations. There are several reasons for this, including the fact that adding vertical polarization or increasing power becomes much cheaper when the reimbursement fund is paying for at least some (and likely most) of your other expenses. Additionally, the repacking algorithm attempted to minimize interference between stations, so there is often more breathing room and, thus, more room to increase power than there was before. Where it likely won't be helpful is with LPTV stations, since those were not protected in the process.

But in your case, other stations will likely improve as well. WFLI will go from 500 kW to 550 kW, but will also add 350 kW of power in the vertical plane and move down in frequency from channel 42 to 23. WTCI already moved to a top-mounted antenna a few years back, but will increase the power on that from 160 kW to 200 kW (likely to be only minimal improvement there, but still an improvement) with only a small change in frequency. WDEF and WELF requested no additional improvements for whatever reason, but WRCB and WTVC both requested additional power despite not being repacked. The one that might be significantly more difficult is WNGH moving to channel 4, but they accepted a pile of cash to make that move.

- Trip
 
harshness

harshness

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Each station's repack is different and some may represent big wins. On the other hand, we've already seen some buddying up that has effectively trashed at least the subchannels due to bandwidth starvation and as some of the beams become more shaped (or otherwise conditioned) to avoid interference, many of the DXers will likely be disappointed.
 
Trip

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On the other hand, we've already seen some buddying up that has effectively trashed at least the subchannels due to bandwidth starvation

Which has nothing to do with signal strength, the point of this thread and my post.

and as some of the beams become more shaped (or otherwise conditioned) to avoid interference,

Full power and Class A stations had their coverage areas preserved, while LPTV stations were not protected, as per what Congress passed. I noted the LPTVs previously, so I'm not sure what you're referring to here. Perhaps you have examples?

many of the DXers will likely be disappointed.

TV is designed to provide service to viewers, not DX targets to DXers. I'm a DXer myself, but it's important to recognize the goal of broadcast television. The ability to DX is a happy accident.

- Trip
 
harshness

harshness

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Obviously, we as viewers are mostly about the number of channels we receive as well as the PQ and AQ of the content. If it is unwatchable, we're not really getting it and the practical coverage (versus technical coverage) goal has not been reached.

What the FCC and stations do to try to preserve mapped coverage area (most of which we have yet to see) will logically be negated if we lose channels because we're on the wrong side of a cardioid or outside of a lobe.

The TS has a really dismal TVFool graph so meeting the licensed area to the exclusion of some stray signal may (or may not) represent a loss.

At this point, all the claims and theory are largely academic but it is important to think about what we might be up against.
 
Trip

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Obviously, we as viewers are mostly about the number of channels we receive as well as the PQ and AQ of the content. If it is unwatchable, we're not really getting it and the practical coverage (versus technical coverage) goal has not been reached.

Which, again, is not the point of this thread. Viewer is happy with content, had problems with signal.

What the FCC and stations do to try to preserve mapped coverage area (most of which we have yet to see) will logically be negated if we lose channels because we're on the wrong side of a cardioid or outside of a lobe.

Which, of course, you'd be on the wrong side of today, since the coverage areas were preserved. I'm not sure what your point is.

- Trip
 
harshness

harshness

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Which, of course, you'd be on the wrong side of today, since the coverage areas were preserved.
I wasn't aware that sides need to be established.

The final judgement will appear in the station's FCC files when all is said and done as to whether the viewer's expectations were ultimately met.
 
Trip

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I wasn't aware that sides need to be established.

It's your own wording. If you are going to be on the wrong side of a cardioid after the repack, then you're almost certainly on the same wrong side of that null today. Again, I don't understand your point.

- Trip
 
andy_horton

andy_horton

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Dec 28, 2010
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Northwest Georgia
Obviously, we as viewers are mostly about the number of channels we receive as well as the PQ and AQ of the content. If it is unwatchable, we're not really getting it and the practical coverage (versus technical coverage) goal has not been reached.

What the FCC and stations do to try to preserve mapped coverage area (most of which we have yet to see) will logically be negated if we lose channels because we're on the wrong side of a cardioid or outside of a lobe.

The TS has a really dismal TVFool graph so meeting the licensed area to the exclusion of some stray signal may (or may not) represent a loss.

At this point, all the claims and theory are largely academic but it is important to think about what we might be up against.
WDSI was the weakest of all stations. The increase in power and any other improvements made made a huge difference in my reception. It went from losing the station during the day to receiving it at around 95% all the time. Even took the preamp off just to test my theory. Same improvement. Antenna has not been moved, no foilage has dropped from trees yet. As other relocate and IF power increases, it should help. Especially the second most difficult WFLI which is about also 35 miles away which must encompass all the Chattanooga DMA which it has always had a hard time with due to signal level output. So it would seem to me at minimum these repacks as they occur could only help full power stations. Maybe with the exception of WNGH Chatsworth GA going from UHF to low VHF. It is also important to realize WNGH is more about serving the GA Blue Ridge Mtns and "bleeds" over into the Chattanooga TN market in some places, more so in GA. Win win for people in GA who have had terrible tvfool reports forever and a day.
 
harshness

harshness

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As other relocate and IF power increases, it should help.
Changes have the potential to go either way. Some of the repacks are reportedly being implemented through trading of towers so someone may be relocating to the towers you couldn't "see" before. Perhaps there is some serious engineering and beam-shaping magic involved where everyone can increase their power without risking interference but I'm dubious.
 
Trip

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Changes have the potential to go either way. Some of the repacks are reportedly being implemented through trading of towers so someone may be relocating to the towers you couldn't "see" before. Perhaps there is some serious engineering and beam-shaping magic involved where everyone can increase their power without risking interference but I'm dubious.

"Reportedly." "Perhaps." "Magic." I hate the way you act like this is all shrouded in mystery when all the applications are already on file (and mostly granted) with full parameters such as coordinates, heights, powers, antenna patterns, etc. such that you can evaluate them and make your own judgments.

- Trip
 
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harshness

harshness

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"Reportedly." "Perhaps." "Magic." I hate the way you act like this is all shrouded in mystery when all the applications are already on file (and mostly granted) with full parameters such as coordinates, heights, powers, antenna patterns, etc. such that you can evaluate them and make your own judgments.
I've been around engineers long enough to know that models are approximations and don't always accurately reflect the realities. Judgement day comes when the stations are all done moving around and we run channel scans to see what we get and what we don't. In the interim all we can do it make sure our antenna(s) cover all the necessary frequencies with some headroom to spare for Next Gen additions.
 

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