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post #11221 of 11336 Old 05-20-2020, 08:28 AM
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Are the majors from Walnut Grove all back at full power, or are some adjustments still going on post repack?
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post #11222 of 11336 Old 05-20-2020, 09:57 AM
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Originally Posted by tapokata View Post
Are the majors from Walnut Grove all back at full power, or are some adjustments still going on post repack?

I looked at the Technical data for each station at Rabbitears and I see this:

KOVR is at 900KW. Will go to 1000KW. Hardly any difference at all.

KSPX is operating on the AUX antenna and at lower power. They should improve.

KTXL is operating at reduced power of 100KW. They will go to 1000KW. Probably not a problem for most people not at the fringes.

Chuck
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post #11223 of 11336 Old 05-21-2020, 12:29 AM
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Originally Posted by Calaveras View Post
KTXL is operating at reduced power of 100KW. They will go to 1000KW. Probably not a problem for most people not at the fringes.
I've had no problems receiving KTXL in Pollock Pines since the repack with the signal strength meter always showing in the "Normal to Good" range. KTXL CAN'T be at only 100KW!
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post #11224 of 11336 Old 05-21-2020, 01:49 AM
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Originally Posted by Smoke_signal View Post
I've had no problems receiving KTXL in Pollock Pines since the repack with the signal strength meter always showing in the "Normal to Good" range. KTXL CAN'T be at only 100KW!
It IS only at 100 kW:
https://www.rabbitears.info/contour....e&site=1&map=Y

You're probably benefiting from the higher elevation. Even at their reduced power there's a bunch of green splotches around Pollock Pines.

This is from the STA they filed back on April 14th
https://enterpriseefiling.fcc.gov/da...71790666402076
Quote:
The instant request is for operation on Channel 22, as authorized, except with 10% power, which is equivalent to a maximum ERP of 100 kW (H), 25 kW (V). This power reduction is necessary as temporary measure to facilitate the construction of the final Channel 22 repack facility. Specifically, the Channel 22 facility will be launched at the reduced power until the new transmitter can be completely assembled and installed, allowing for full authorized power on Channel 22. It is expected to take approximately 2 months to complete the new transmitter system and make in fully operational.

The switchover to Channel 22 at 10% power is anticipated on approximately April 29, 2020 barring further unforeseen events.

The progress report they filed earlier this month says they're not finished, and they have yet to file a license to cover to indicate that the work is completed:
Quote:
Waiting on installation of final transmitter and tweaks to antenna which were delayed due to pandemic.

In order to meet the repack technical standards KTXL is replacing its current top-mounted antenna with a new top-mounted antenna on the same tower. There are delays in the tower crew finishing the job, and a CP extension has been filed.
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post #11225 of 11336 Old 05-21-2020, 07:25 AM
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Originally Posted by Smoke_signal View Post
I've had no problems receiving KTXL in Pollock Pines since the repack with the signal strength meter always showing in the "Normal to Good" range. KTXL CAN'T be at only 100KW!
100KW is 10 dB down. When I was in Calaveras County KTXL's measured Noise Margin was 32 dB. If the Noise Margin dropped to 22 dB I would not have noticed. When I lost reception of a Sacramento station it was due to some reduction in signal strength plus a big increase in multipath. Signals never got too weak to receive them. Multipath was always the factor that prevented reception.

I added an image showing KCRA with an average signal and a weak signal (yellow). KCRA's Noise Margin was 33 dB with an average signal (red). The signal is just 13 dB weaker yet I could not receive the station. The multipath was too high when the signal dropped.

Chuck
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post #11226 of 11336 Old 05-22-2020, 01:14 AM
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Originally Posted by KyL416 View Post
It IS only at 100 kW:
https://www.rabbitears.info/contour....e&site=1&map=Y

You're probably benefiting from the higher elevation. Even at their reduced power there's a bunch of green splotches around Pollock Pines.
I looked at the rabbitears Longley-Rice coverage maps for KTXL and KCRA in the Pollock Pines area. The "splotch" patterns for my location are nearly identical except for a little more yellow showing than red for the stronger KCRA 1000KW signal. Yet I almost never receive KCRA, whereas KTXL has always been received nearly all the time. That just means the Longley-Rice maps are just nice looking meaningless abstract art as far as I'm concerned. Reality is the only "map" I trust. KCRA needs to replace their overly high gain narrow beam antenna, period! KTXL uses a lower gain wider beam antenna, and THAT'S what makes the difference!!!!!!!!!!!!
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post #11227 of 11336 Old 05-22-2020, 08:46 AM
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Originally Posted by Smoke_signal View Post
I looked at the rabbitears Longley-Rice coverage maps for KTXL and KCRA in the Pollock Pines area. The "splotch" patterns for my location are nearly identical except for a little more yellow showing than red for the stronger KCRA 1000KW signal. Yet I almost never receive KCRA, whereas KTXL has always been received nearly all the time. That just means the Longley-Rice maps are just nice looking meaningless abstract art as far as I'm concerned. Reality is the only "map" I trust. KCRA needs to replace their overly high gain narrow beam antenna, period! KTXL uses a lower gain wider beam antenna, and THAT'S what makes the difference!!!!!!!!!!!!
The Longley-Rice plots take into account the horizontal antenna pattern but they don't take into account the vertical pattern. If they did I'm sure the predicted signal strength for your area would be much lower. You can see this in predictions for people very close to the transmitters with Noise Margins in the +60 to +80 dB range. They don't see these kind of signals because they are far below the main antenna lobe where signals are a few percent of the main lobe. Longley-Rice assumes they are in the main lobe giving NMs far higher than reality.

Some years ago I visited Larry and captured spectrum analyzer traces of most of his stations. Look how terrible some of his channels looked because is 18 degrees below the main lobe. I also attached the vertical antenna plots of the Sutro antennas. Note where -18 degrees is on the plot.

I still wonder what your signal strengths actually are. Is your problem signal strength or multipath? Without looking at the signals on a spectrum analyzer you'll never know.

Chuck
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post #11228 of 11336 Old 05-22-2020, 09:37 PM
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Originally Posted by Calaveras View Post
I still wonder what your signal strengths actually are. Is your problem signal strength or multipath? Without looking at the signals on a spectrum analyzer you'll never know.
I don't need a spectrum analyzer to know it's NOT multipath. When KCRA is/was on their backup antenna I received the station. On their main antenna, nothing!!!! Their high gain antenna is the problem. If it was multipath, a strong signal would still show on my TV's meter even if not viewable. There is no strong signal at any time other than when KCRA is, rarely, actually viewable. NO OTHER WALNUT GROVE STATION HAS THIS PROBLEM!!!! Even KQCA has become viewable since the repack using the same antenna, like KMAX was viewable when it was on the same antenna. Since some channels are viewable using this antenna, the problem does seem to depend on the channel frequency, likely due to the frequency characteristics of the high-gain, wide-band, multi-channel panel antenna and its node pattern dependent on the horizontal azimuth position. These signal strength nodes are more prominent on this type of antenna, another reason for NOT using this antenna!!!

See "FIGURE 28" on Page 30 of:
https://www.itu.int/dms_pubrec/itu-r...0-S!!PDF-E.pdf

Rec. ITU-R BS.1195 1
RECOMMENDATION ITU-R BS.1195
TRANSMITTING ANTENNA CHARACTERISTICS AT VHF AND UHF

7.3.3.1 Omnidirectional panel antenna systems

FIGURE 28
Azimuth pattern of a wide-band horizontally polarized UHF antenna
system measured at 470, 550 and 620 MHz

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post #11229 of 11336 Old 05-23-2020, 08:33 AM
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If it was multipath, a strong signal would still show on my TV's meter even if not viewable.
So your TV has a real signal strength meter. As you well know, most TVs only have a signal quality meter even if they call it a signal strength meter. I know the HDHR has a signal strength meter and my Sony does too. Beyond those I don't know of any others.

We've been through this many times over the years and I agree with the issues you raise about the KCRA antenna. But lots of people, including myself, are/were able to receive KCRA in the foothills. It doesn't make any sense that the KCRA antenna issues make it too weak just for you. It's not that selective.

Attached is a spectrum analyzer trace of KCRA taken from Arnold, CA, about 4100' and 62 miles from the transmitter, a very similar location to yours. It's not a strong signal, but it's in line with other Walnut Grove stations. It seems impossible that KCRA would be okay in Arnold but dramatically different where you are. This is why I remain unconvinced that your theory is correct. It doesn't jibe with other realities. I know you believe your theory but you've never actually shown us any measurements to back it up.

I also attached a composite UHF spectrum taken from my Mountain Ranch location in January 2015. It's a composite because I pointed the antenna in many directions to capture all the stations and then combined the individual stations into one trace in Photoshop. You can see that KCRA is sort of in the middle of the pack of Walnut Grove Stations. If any station was suffering from an antenna issue it was KQCA.


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Originally Posted by Smoke_signal View Post
These signal strength nodes are more prominent on this type of antenna, another reason for NOT using this antenna!!!
These antennas are in common use. They're used on Sutro tower and they're in use by some of my stations in Tucson. Despite the uneven pattern, I have not seen any issues with them.

Chuck
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post #11230 of 11336 Old 05-23-2020, 09:11 PM
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So your TV has a real signal strength meter. As you well know, most TVs only have a signal quality meter even if they call it a signal strength meter. I know the HDHR has a signal strength meter and my Sony does too. Beyond those I don't know of any others.

We've been through this many times over the years and I agree with the issues you raise about the KCRA antenna. But lots of people, including myself, are/were able to receive KCRA in the foothills. It doesn't make any sense that the KCRA antenna issues make it too weak just for you. It's not that selective.

Attached is a spectrum analyzer trace of KCRA taken from Arnold, CA, about 4100' and 62 miles from the transmitter, a very similar location to yours. It's not a strong signal, but it's in line with other Walnut Grove stations. It seems impossible that KCRA would be okay in Arnold but dramatically different where you are. This is why I remain unconvinced that your theory is correct. It doesn't jibe with other realities. I know you believe your theory but you've never actually shown us any measurements to back it up.

I also attached a composite UHF spectrum taken from my Mountain Ranch location in January 2015. It's a composite because I pointed the antenna in many directions to capture all the stations and then combined the individual stations into one trace in Photoshop. You can see that KCRA is sort of in the middle of the pack of Walnut Grove Stations. If any station was suffering from an antenna issue it was KQCA.




These antennas are in common use. They're used on Sutro tower and they're in use by some of my stations in Tucson. Despite the uneven pattern, I have not seen any issues with them.

Chuck
You are too hung up with your spectrum analyzer. How do you explain that I can now receive KQCA after the repack frequency change? Did KQCA multipath suddenly vanish? What needs to be measured is the azimuth pattern for the different frequencies for THAT specific antenna at Walnut Grove. You know absolutely nothing about that pattern even with your spectrum analyzer! Why would KCRA be the ONLY Walnut Grove station having multipath issues here? Why would I have received DTV KCRA, mostly without problem, on their backup antenna until the day KCRA switched to the current panel antenna after the analog signal was turned off, and received KCRA whenever they switched back to the backup antenna? Your Mountain Ranch location was clearly in the right position to avoid a low signal antenna azimuth. My location is clearly at a low signal azimuth. And I am pretty sure I am NOT the ONLY viewer affected by the current KCRA antenna. I am, however, a viewer technically educated with physics and engineering degrees and KNOW when something is not right and what it might be. If KCRA rotated their antenna just a little, YOU might have been the one without the signal!
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post #11231 of 11336 Old 05-24-2020, 08:13 AM
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You are too hung up with your spectrum analyzer. How do you explain that I can now receive KQCA after the repack frequency change? Did KQCA multipath suddenly vanish? What needs to be measured is the azimuth pattern for the different frequencies for THAT specific antenna at Walnut Grove. You know absolutely nothing about that pattern even with your spectrum analyzer! Why would KCRA be the ONLY Walnut Grove station having multipath issues here? Why would I have received DTV KCRA, mostly without problem, on their backup antenna until the day KCRA switched to the current panel antenna after the analog signal was turned off, and received KCRA whenever they switched back to the backup antenna? Your Mountain Ranch location was clearly in the right position to avoid a low signal antenna azimuth. My location is clearly at a low signal azimuth. And I am pretty sure I am NOT the ONLY viewer affected by the current KCRA antenna. I am, however, a viewer technically educated with physics and engineering degrees and KNOW when something is not right and what it might be. If KCRA rotated their antenna just a little, YOU might have been the one without the signal!
Multipath varies drastically with frequency. It's totally possible for it to be much different on its new channel.

So here's some data. The attached image shows a comparison of the UHF band between my location in yellow and my friend's location in magenta. Bob's location is east of Placerville just off of Pleasant Valley Road down the hill from you. It's about 2800' and less than 1 degree difference in azimuth from Walnut Grove. The difference in elevation is about 1/4 degree between you and him. The image shows a comparison of the UHF band between my location in yellow and his location in magenta. His antenna was a CM4251 dish. Overall my signals are better except for KTXL. The KCRA signal is not the weakest signal. It's sort of in the middle of the pack. I'm not saying he never had issues with KCRA, but he had issues with all the Sacramento stations at times, some more than others, just like I did. I don't know for sure exactly what your problem is with KCRA, but there's no evidence that's it's too weak in your direction. You've just latched on to a theory and come to believe it with no supporting data. And yes, the spectrum analyzer is a very useful tool that can help diagnose an array of problems.

Chuck
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post #11232 of 11336 Old 05-24-2020, 09:54 AM
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Originally Posted by Calaveras View Post
And yes, the spectrum analyzer is a very useful tool that can help diagnose an array of problems.

Chuck
Quick question.
What is the "constellation diagram" mode used for.
In that mode a bunch of bars slowly load up and cycle.
Reading online the goal is more skinny lines.

Is that feature useful for much ?

I find the most useful feature is displaying 5 channels at once. Not adjacent, programmed in.
It is a BER meter.... on all 5 channels at once.
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post #11233 of 11336 Old 05-25-2020, 12:50 AM
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You've just latched on to a theory and come to believe it with no supporting data.
You have failed to answer or even give a plausible answer to any of my questions given in my last post. You keep saying multipath is the explanation.

I have no access to the manufacturer's specific antenna test data. Panel antennas require complex mathematical analysis to design them, and test results are the only way to verify the analysis is correct. A high-gain wide-band panel antenna requires numerous panel modules stacked vertically and radially. All these modules are each separated by a large variety of distances from each other, each sending out separate signals. The signals from each module have phase differences with respect to the signals from every other module. The antenna designer must consider all these phase differences to form the desired beam. This is a wide-band antenna and covers a wide range of frequencies. Each frequency has a different degree of phase shift, and so each frequency will have a different signal strength at ALL azimuth AND elevation angles. Every frequency has a different degree of phase shift and signal strength compared to every other frequency. The manufacturer makes the best compromise in design over the entire range of frequencies.

KMAX and now, with a frequency change, KQCA have been viewable on this antenna. KQCA, in fact, now has a very strong signal. KCRA, always fixed at channel 35, has always been unviewable from this antenna. In past years, KCRA has been at least somewhat viewable from their backup antenna at reduced power. Their backup antenna was used frequently during the first years of DTV. I haven't been tuned to KCRA in recent years to experience their backup antenna of late. ALL OTHER WALNUT GROVE STATIONS DO NOT HAVE THE PROBLEM KCRA HAS. Why would multipath be a UNIQUE problem ONLY for KCRA? Multipath situations would change with varying weather conditions as well as with vegetation. There is no change in KCRA's reception other than during temperature inversions affecting ALL other channels. Further, my 91XG receiving antenna is pointed towards the sky, above tree height and above surrounding hillsides where there IS NO multipath. By simple logic and deduction, the characteristics of the high-gain wide-band panel antenna, affected by distance, azimuth and elevation angle is the most likely and logical reason that KCRA is unviewable at my location from this panel antenna.

If someone would post when KCRA is on their backup antenna, then I could verify their main antenna is at fault. I've looked for info on the KCRA auxiliary (backup) antenna. This is all I could find:

http://licensing.fcc.gov/prod/cdbs/p...es/1333296.pdf
Antenna Type: Non-Directional
Beam Tilt: 0.7 Degrees Electrical
Description: DIE, TFU-24GTH/VP-R 06
Height of radiation center above ground: 463 Meters

This is the ideal type of slot antenna I wish KCRA was using as their main antenna! It is not clear what ERP is being used for backup transmitting power. The document just says maximum ERP is 1000kW. I would love to see how KCRA behaves on backup today!

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post #11234 of 11336 Old 05-25-2020, 08:07 AM
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If someone would post when KCRA is on their backup antenna, then I could verify their main antenna is at fault. I've looked for info on the KCRA auxiliary (backup) antenna. This is all I could find:

http://licensing.fcc.gov/prod/cdbs/p...es/1333296.pdf
Antenna Type: Non-Directional
Beam Tilt: 0.7 Degrees Electrical
Description: DIE, TFU-24GTH/VP-R 06
Height of radiation center above ground: 463 Meters

This is the ideal type of slot antenna I wish KCRA was using as their main antenna! It is not clear what ERP is being used for backup transmitting power. The document just says maximum ERP is 1000kW. I would love to see how KCRA behaves on backup today!
I have answered your questions but you don't like the answers. I'll try again.

KCRA does not have a backup antenna. They have no license for one. KQCA does have a main and backup antenna. Both are licensed. Check the listing under Technical Data on Rabbitears. Mulitpath changes with frequency. I totally expected that the KQCA signal would be different when they changed frequency.

Before the 2009 digital transition, KCRA was using a different and lower antenna. It had terrible multipath issues at my location. The post transition (and current) antenna was much better. They no longer have a license for the old antenna.

I'm not claiming the KCRA antenna is causing your multipath, if that's what's going on. Your location plus a combination of local factors is causing it. I just proved that KCRA has an acceptable signal in your direction. KCRA is the only problem station at your location because you were just unlucky. Rotating their antenna would not affect your signal.

I had a similar issue in Mountain Ranch with KXTV except it wasn't as bad. KXTV had an equal signal to all the other Walnut Grove stations but it's SNR was only around 20 dB. My local conditions caused this, not the KXTV antenna. All the other Walnut Grove stations were 5-10 dB higher.

Since you steadfastly refuse to provide any data, my best guess is multipath problems. You've never even shared your TV Fool report or now, your Rabbitears report.

I'm not sure what is going on with the KCRA/KQCA antenna. Neither station shows an antenna pattern in their FCC listing. They just say "omni-directional." Usually in this case that means the antenna is truly omni-directional, not one of those antennas with the ripply pattern. Any antenna that is not truly omni-directional has a pattern shown in the FCC listing. I have to go with the FCC data and the antenna is truly omni-directional. The documents you linked to are not for the exact KCRA antenna so we don't know for sure what the pattern looks like.

Chuck
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post #11235 of 11336 Old 05-25-2020, 08:54 AM
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I'm not sure what is going on with the KCRA/KQCA antenna. Neither station shows an antenna pattern in their FCC listing. They just say "omni-directional." Usually in this case that means the antenna is truly omni-directional, not one of those antennas with the ripply pattern. Any antenna that is not truly omni-directional has a pattern shown in the FCC listing. I have to go with the FCC data and the antenna is truly omni-directional. The documents you linked to are not for the exact KCRA antenna so we don't know for sure what the pattern looks like.
One correction--there is no such thing as a perfect omni with TV transmit antennas. FCC rules permit a station to license an omnioid antenna as a perfect omni within certain parameters which I don't have handy.

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post #11236 of 11336 Old 05-25-2020, 10:18 AM
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Originally Posted by Smoke_signal View Post
If someone would post when KCRA is on their backup antenna, then I could verify their main antenna is at fault. I've looked for info on the KCRA auxiliary (backup) antenna. This is all I could find:

http://licensing.fcc.gov/prod/cdbs/p...es/1333296.pdf
Antenna Type: Non-Directional
Beam Tilt: 0.7 Degrees Electrical
Description: DIE, TFU-24GTH/VP-R 06
Height of radiation center above ground: 463 Meters

This is the ideal type of slot antenna I wish KCRA was using as their main antenna! It is not clear what ERP is being used for backup transmitting power. The document just says maximum ERP is 1000kW. I would love to see how KCRA behaves on backup today!
I have answered your questions but you don't like the answers. I'll try again.

KCRA does not have a backup antenna. They have no license for one. KQCA does have a main and backup antenna. Both are licensed. Check the listing under Technical Data on Rabbitears. Mulitpath changes with frequency. I totally expected that the KQCA signal would be different when they changed frequency.

Before the 2009 digital transition, KCRA was using a different and lower antenna. It had terrible multipath issues at my location. The post transition (and current) antenna was much better. They no longer have a license for the old antenna.

I'm not claiming the KCRA antenna is causing your multipath, if that's what's going on. Your location plus a combination of local factors is causing it. I just proved that KCRA has an acceptable signal in your direction. KCRA is the only problem station at your location because you were just unlucky. Rotating their antenna would not affect your signal.

I had a similar issue in Mountain Ranch with KXTV except it wasn't as bad. KXTV had an equal signal to all the other Walnut Grove stations but it's SNR was only around 20 dB. My local conditions caused this, not the KXTV antenna. All the other Walnut Grove stations were 5-10 dB higher.

Since you steadfastly refuse to provide any data, my best guess is multipath problems. You've never even shared your TV Fool report or now, your Rabbitears report.

I'm not sure what is going on with the KCRA/KQCA antenna. Neither station shows an antenna pattern in their FCC listing. They just say "omni-directional." Usually in this case that means the antenna is truly omni-directional, not one of those antennas with the ripply pattern. Any antenna that is not truly omni-directional has a pattern shown in the FCC listing. I have to go with the FCC data and the antenna is truly omni-directional. The documents you linked to are not for the exact KCRA antenna so we don't know for sure what the pattern looks like.

Chuck
KCRA most certainly does have an aux. It’s at Transtower. And they use it more than you might think.

All this banter about KCRA’s main is kind of pointless. Nothing has changed with their facility in years. They were already within the core of remaining channels post-repack. The only thing that has changed is interference from adjacents.
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post #11237 of 11336 Old 05-25-2020, 10:22 AM
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Originally Posted by Trip in VA View Post
One correction--there is no such thing as a perfect omni with TV transmit antennas. FCC rules permit a station to license an omnioid antenna as a perfect omni within certain parameters which I don't have handy.

- Trip

Okay. Makes sense. I wondered how a horizontal polarized omni was possible. So it's pretty close. Probably less variation than anyone would notice in the real world. Certainly not enough to prevent reception. It would be interesting to know the maximum variation should you ever run across it.

Chuck
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post #11238 of 11336 Old 05-25-2020, 10:57 AM
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Originally Posted by Spoon1369 View Post
KCRA most certainly does have an aux. It’s at Transtower. And they use it more than you might think.

All this banter about KCRA’s main is kind of pointless. Nothing has changed with their facility in years. They were already within the core of remaining channels post-repack. The only thing that has changed is interference from adjacents.

Please provide a link to the license for this aux transmitter. I don't see it in the FCC database. Most of the Walnut Grove stations have either a license or a construction permit for a back-up station. KCRA does not. They used to operate from that shorter tower back around the transition but not for a long time.

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post #11239 of 11336 Old 05-25-2020, 11:24 AM
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Originally Posted by 888CALLFCC View Post
Quick question.
What is the "constellation diagram" mode used for.
In that mode a bunch of bars slowly load up and cycle.
Reading online the goal is more skinny lines.

Is that feature useful for much ?

I find the most useful feature is displaying 5 channels at once. Not adjacent, programmed in.
It is a BER meter.... on all 5 channels at once.
I'm not an expert on this. I've seen these. The kind I've seen the most are the dots. The narrower the lines or the more tightly clustered the dots the higher the SNR. If you have SNR I don't know what additional you get knowing BER. Once upon a time I worked on some equipment where we measured BER (not DTV). The measurement equipment had a constellation display with dots. We did not have SNR.

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post #11240 of 11336 Old 05-25-2020, 01:12 PM
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Originally Posted by Calaveras View Post
Please provide a link to the license for this aux transmitter. I don't see it in the FCC database. Most of the Walnut Grove stations have either a license or a construction permit for a back-up station. KCRA does not. They used to operate from that shorter tower back around the transition but not for a long time.
I checked with my contact over there -- he said that yes, they do have a complete backup on Transtower.
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post #11241 of 11336 Old 05-25-2020, 04:14 PM
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Originally Posted by videojanitor View Post
I checked with my contact over there -- he said that yes, they do have a complete backup on Transtower.

After searching all the listings in the FCC LMS for KCRA I finally found what I believe is the License to Cover for the facility on the Transtower back in 2004. Lat/Lon listed in the App are correct and the antenna height is about 100m lower.

https://enterpriseefiling.fcc.gov/da...6c0ea&goBack=N

Why this doesn't show up in TV Query I have no idea. All the other licensed facilities seem to appear in TV Query. These inconsistencies in the FCC database drive me crazy. You have to have inside information to be sure what information you read is correct.

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post #11242 of 11336 Old 05-25-2020, 04:22 PM
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Originally Posted by Calaveras View Post
These inconsistencies in the FCC database drive me crazy. You have to have inside information to be sure what information you read is correct.
Agreed 100%.
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post #11243 of 11336 Old 05-25-2020, 05:19 PM
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Originally Posted by Calaveras View Post
Why this doesn't show up in TV Query I have no idea. All the other licensed facilities seem to appear in TV Query.
It looks like something got lost in the shuffle along the way when they imported the CDBS data to the LMS. The CDBS applications and items have more details in the various public notices, correspondences and attachments that didn't make it over to the LMS entries.

Transtower was their original DTV facility first granted in 1998 (BPCDT-19980731KL):
LMS application

They filed a license to cover for that in 2004 (BLCDT-20040122ADR):
CDBS Application
LMS Application

They filed a modification to move to their own tower in 2008 (BPCDT-20080208AEM):
CDBS Application
LMS Application

They filed for the license to cover for that in 2009 (BLCDT-20090915ACY).
CDBS Application
LMS Application

A few weeks later, they filed another modification to make the previous Transtower facility their Aux facility (BXMLCDT-20090930AOO), but since it was based on the license to cover from 2004, which by that point was already considered superceded for the 2009 facility, its current status might have gotten lost in translation when they imported the CDBS data into the new LMS system:
CDBS Application
LMS Application

And to make things more complicated, in 2011 they had to file an amendment to the 2009 license to cover and a modification (BMLCDT-20110630AGB) to correct a typo in the antenna type listed in the 2008 modification:
CDBS Amended Application
LMS Amended Application
CDBS Modification
LMS Modification
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Last edited by KyL416; 05-25-2020 at 05:39 PM.
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post #11244 of 11336 Old 05-26-2020, 04:55 AM
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Originally Posted by Calaveras View Post
Rotating their antenna would not affect your signal.
And just how do you KNOW that?????????? Your one time spectrum image of Bob's reception does not prove anything. Bob's location is NOT MY location. And only one image for one time on one day is NOT representative of what is going on over months of daily observations.

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Originally Posted by Calaveras View Post
I'm not sure what is going on with the KCRA/KQCA antenna. Neither station shows an antenna pattern in their FCC listing. They just say "omni-directional." Usually in this case that means the antenna is truly omni-directional, not one of those antennas with the ripply pattern. Any antenna that is not truly omni-directional has a pattern shown in the FCC listing. I have to go with the FCC data and the antenna is truly omni-directional. The documents you linked to are not for the exact KCRA antenna so we don't know for sure what the pattern looks like.
Just for your info, here are representative azimuth and elevation patterns for the Dielectric Deltastar Wide-Band UHF Panel Antennas. (This is the KCRA/KQCA antenna.) Note: patterns are representative only, since patterns differ with channel frequency!!!! You would have to talk to Dielectric to get the REAL data if they would even release it.

Azimuth Patterns for Dielectric Deltastar Wide-Band UHF Panel Antennas
https://www.dielectric.com/antenna/tu-series-deltastar/
(Click on "Azimuth Images" tab.)

Elevation Patterns for Dielectric Deltastar Wide-Band UHF Panel Antennas
http://www.dielectric.com/wp-content...-Deltalite.pdf
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post #11245 of 11336 Old 05-26-2020, 07:31 AM
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Originally Posted by Smoke_signal View Post
And just how do you KNOW that?????????? Your one time spectrum image of Bob's reception does not prove anything. Bob's location is NOT MY location. And only one image for one time on one day is NOT representative of what is going on over months of daily observations.
Yes it is. The azimuth difference is 0.8 degrees and the elevation difference is around 0.2 degrees. The signal will not vary much at all with such a small difference. Signals don't vary over months except due to the effects of temperature inversions.


Quote:
Originally Posted by Smoke_signal View Post
Just for your info, here are representative azimuth and elevation patterns for the Dielectric Deltastar Wide-Band UHF Panel Antennas. (This is the KCRA/KQCA antenna.) Note: patterns are representative only, since patterns differ with channel frequency!!!! You would have to talk to Dielectric to get the REAL data if they would even release it.

Azimuth Patterns for Dielectric Deltastar Wide-Band UHF Panel Antennas
https://www.dielectric.com/antenna/tu-series-deltastar/
(Click on "Azimuth Images" tab.)

Elevation Patterns for Dielectric Deltastar Wide-Band UHF Panel Antennas
http://www.dielectric.com/wp-content...-Deltalite.pdf
This make sense. The azimuth pattern variance is about 1.4 dB. That's so small that it would be unnoticed by almost everyone. That would not be the difference between good reception and no reception.

Chuck
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post #11246 of 11336 Old 05-26-2020, 02:10 PM
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Originally Posted by Calaveras View Post
Please provide a link to the license for this aux transmitter. I don't see it in the FCC database. Most of the Walnut Grove stations have either a license or a construction permit for a back-up station. KCRA does not. They used to operate from that shorter tower back around the transition but not for a long time.

Chuck

KCRA has maintained a backup at Transtower for many years. KXTV gave up their backup about 10 years ago.
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post #11247 of 11336 Old 05-26-2020, 02:14 PM
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Originally Posted by Smoke_signal View Post
And just how do you KNOW that?????????? Your one time spectrum image of Bob's reception does not prove anything. Bob's location is NOT MY location. And only one image for one time on one day is NOT representative of what is going on over months of daily observations.


Just for your info, here are representative azimuth and elevation patterns for the Dielectric Deltastar Wide-Band UHF Panel Antennas. (This is the KCRA/KQCA antenna.) Note: patterns are representative only, since patterns differ with channel frequency!!!! You would have to talk to Dielectric to get the REAL data if they would even release it.

Azimuth Patterns for Dielectric Deltastar Wide-Band UHF Panel Antennas
https://www.dielectric.com/antenna/tu-series-deltastar/
(Click on "Azimuth Images" tab.)

Elevation Patterns for Dielectric Deltastar Wide-Band UHF Panel Antennas
http://www.dielectric.com/wp-content...-Deltalite.pdf

I can say one thing.. KCRA is NOT going to do anything about this this issue. So what is the use arguing about this at all? With the current COVID situation draining revenue, spending money on another antenna is never ever going to happen now.



Bill H.
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post #11248 of 11336 Old 05-26-2020, 02:34 PM
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Originally Posted by wndhh1 View Post
KCRA has maintained a backup at Transtower for many years. KXTV gave up their backup about 10 years ago.
I think you're behind on the conversation. We found the License to Cover grant from 2004 for the back-up facility.

KXTV has a construction permit for a back-up antenna on the same tower as their current antenna. Looks like they have not given up after all.

Chuck
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post #11249 of 11336 Old 05-26-2020, 02:47 PM
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Originally Posted by wndhh1 View Post
I can say one thing.. KCRA is NOT going to do anything about this this issue. So what is the use arguing about this at all?

We're not arguing about KCRA changing their antenna. We all know that's not going to happen. The argument is about whether KCRA's antenna is causing his lack of reception. I've presented evidence that I believe shows KCRA's signal is adequate in the direction of Pollock Pines. He believes otherwise but he has not presented any evidence to support that claim. Linking to data sheets (which don't support the claim anyway) and appeal to authority (himself) is not evidence.

Even if KCRA is weaker at his location, it's more likely it has to do with what is between his antenna and the transmitter (vegetation) than it is the KCRA antenna.

Chuck
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post #11250 of 11336 Old 05-26-2020, 10:32 PM
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Unhappy Memories

I remember when this thread was actually useful.
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