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Quote:
Originally Posted by rackerby /forum/post/16716575


Alright, I give up... What the heck is KVIE-DM referenced on tvfool.com?

It was a part of the paperwork required to get the channel 9 allotment. DM = "Digital Modification" or something like that.


If you look really hard, you'll find a few stations like maybe KCSM-DR as a call sign, which means "Digital Reassignment" or something. KCSM had their digital channel changed from 59 to 43 at some point.


- Trip
 

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Quote:
Originally Posted by JNinCA /forum/post/16716069


IMHO, I think VHF hi has BETTER propagation than UHF. I think the problem we are seeing with all the people unable to get KVIE/KXTV probably says more about how rotten so many antennas (Silver Sensor, Square Shooter, etc.) are at VHF.

That's part of it, but the fact is the long wavelengths of VHF don't penetrate well through complex building structures, while the shorter ones, especially at the upper end of the band like KSPX and KQCA, bore through much better. It's true regardless of the modulation--back in the analog days, ch. 6 was unwatchable at my mom's former installation on the south end of Lodi (indoor antenna on the wrong side of a building) even with the rabbit ears elements extended to an exact half wavelength of KVIE's transmit frequency. On the other hand, all of the UHF channels were solid with a simple 8 inch loop.

Quote:
Originally Posted by JNinCA /forum/post/16716069


Considering how much you've already tried, I can only suggest a different converter box (everyone seems to think the Zenith has terrific reception) or stepping up to mounting a 4228 indoors

Naw, she has a nice Toshiba HDTV, so changing the tuner is not an option. I doubt that any different ATSC tuner would matter. This issue is all about antennas and wave propagation under varying circumstances.


If anyone of this group attends the seminar, be sure to look me up and say hello. Bright green polo shirt, Oakland A's baseball cap.


--Ron
 

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A friend of mine who lives in Arnold (65 miles from Walnut Grove) receives KVIE and KXTV fine. He has a 30 year old roof mounted VHF antenna. No UHF antennas up there because they all live in a pine forest and UHF is a no go. He also can receive KGO, KSBW, and KCBA.


Another friend in Rail Road Flat (55 miles from Walnut Grove) also in a bunch of pine trees receives KVIE and KXTV. He does manage to receive KCRA as his only Walnut Grove UHF station. He has a VHF/UHF roof mounted antenna.


Another guy 1000' down the road from the above guy with fewer pine trees receives everything except KQCA. He's using a system designed by me, a pair of 91XGs and a YA-1713 with preamps. A look at the spectrum analyzer shows that the KQCA signal is almost non-existent there. Can't fix that unless we move the antenna.


Accumulating circumstantial evidence is leading me to believe the entire problem is multipath when these stations can't be received. The reports of just about any antenna receiving/not receiving any particular station indoors is more of an indication of lucky positioning and response of the antenna and not that one indoor antenna is dramatically better than another. Same goes for outdoor UHF antennas being used for hi VHF. I get the best lo VHF reception on my hi VHF antennas if I point them 45 degrees away from the station. That doesn't make them decent for lo VHF though. Actually my 17-30 Mhz ham log periodic is a better lo VHF antenna than the hi VHF antennas are.



The surest way to solve these reception problems is to accept that DTV is sensitive to multipath and you need an antenna system that will minimize that problem. In most cases that means an outdoor antenna designed to receive both UHF and hi VHF.


Chuck
 

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Howdy all I'm new and don't know if I'm butting in ,in the wrong place. I lost my channel (3, kiem Eureka CA) in the digital switch. They are now 3.1, but still VHF. The digital signal is too weak. As I'm only after one channel I want to try a custom dipole instead of an amp. We are off the grid and any fraction of an amp adds up. I have lots of room, lots of coax, and lots of copper, (solid core, maybe 12G)


Question, if I make say a 12, 25, 50 foot simple "T" dipole could that help? I know their direction, but not the MHz Any thoughts? On that scale would the length be specific for their VHF brodcast? Thanks, Don.
 

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Quote:
Originally Posted by thatdonguy7 /forum/post/16719356


Howdy all I'm new and don't know if I'm butting in ,in the wrong place. I lost my channel (3, kiem Eureka CA) in the digital switch. They are now 3.1, but still VHF. The digital signal is too weak. As I'm only after one channel I want to try a custom dipole instead of an amp. We are off the grid and any fraction of an amp adds up. I have lots of room, lots of coax, and lots of copper, (solid core, maybe 12G)


Question, if I make say a 12, 25, 50 foot simple "T" dipole could that help? I know their direction, but not the MHz Any thoughts? On that scale would the length be specific for their VHF brodcast? Thanks, Don.

A dipole for the middle of channel 3 (63 MHz) is about 88". Since a dipole impedance is 75 ohms, you can feed it with RG-6 directly. It may be helpful to make a balun though. Try 4 or 5 turns of RG-6 about 3" in diameter placed right at the feed point. That'll make the dipole have a better pattern.


Chuck
 

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Back from the seminar. Good experience. Reps from KVIE & KXTV did very well answering questions.


They had an analog TV plus CECB set up with two indoor antennas, a conventional rabbit ears with UHF loop, and a Terk 5. The Terk displayed a solid signal on KVIE (ground floor, wrong side of building, near I-5 and West El Camino) while the rabbit ears showed zilch.


One neat trick I picked up on that I hadn't thought of before: when struggling with VHF reception problems on the two stations, bypass your converter (if you're using one) and tune in the Nighlight transmission on analog 6. Optimize your antenna system for the best possible signal, then return to the digital mode, rescan, etc. That eliminates the hit-and-miss problem of trying to capture KVIE DT (for example) for the first time when you haven't yet figured out the best antenna type, direction, etc.


The bad news is that all Nightlight transmissions go away on July 12th.


One other technique that I knew of but haven't focused upon very much: when troubleshooting weird DTV reception problems (i.e. DTV channels that are there, then disappear), do a double rescan--disconnect the antenna, do a scan (wiping out all old channel memories), then reconnect and scan again, thus storing only current channels.


Lastly, both stations confirmed that they are at max transmitter power and their final antenna position on the tower, although the KVIE guy was strangely evasive when I asked him if any subsequent changes were in the works. Hmmm.


--Ron
 

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Quote:
Originally Posted by El Carbonite /forum/post/16721703


Is News10 going HD soon? It looks like they're now broadcasting HD sidebars but still in 4:3 SD.

By News10, do you mean the local news broadcast? That will not be going 16:9 HD anytime soon. That would require a large investment by Gannett, and Gannett has apparently said no.


I told the KXTV engineer that I didn't really care if it went 16:9 HD, if it would just start broadcasting an Active Format Descriptor so I didn't have to look at a postage stamp image. He said that too is out of the control of the local station. They have to wait for ABC, which I thought was not completely accurate. If it is their local production, they should insert the AFD.


BTW, those colored "bars" on the edge of the image drive me nuts. I'd rather have black. It's far less distracting.
 

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Quote:
Originally Posted by KG7OR /forum/post/16720712


They had an analog TV plus CECB set up with two indoor antennas, a conventional rabbit ears with UHF loop, and a Terk 5. The Terk displayed a solid signal on KVIE (ground floor, wrong side of building, near I-5 and West El Camino) while the rabbit ears showed zilch.

That is really interesting. I've already asked EscapeVelocity about this. I don't want to second guess the engineers at the station, but I don't see how any omni directional antenna can out perform a directional antenna.

Quote:
Originally Posted by KG7OR /forum/post/16720712


Lastly, both stations confirmed that they are at max transmitter power and their final antenna position on the tower, although the KVIE guy was strangely evasive when I asked him if any subsequent changes were in the works. Hmmm.


--Ron

Let's flesh out what "max" means. The FCC limit for VHF DTV is 160000 watts in Zone II. These two are nowhere close to that. They are at the max output of the transmitter they bought. They could hook up a second transmitter to double output if they could afford it. KVIE cannot. However, I still expect that to be the long term solution.


I still believe you will eventually have to install a small outdoor Yagi in your mother's closet to get KVIE/KXTV. You are certainly not alone with your VHF problems. VHF Throws Wrench In DTV Transition
 

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EV didn't test the TV5 for VHF. A really directional antenna can be completely foiled by trees, there's lots of them in Sacramento. It's a world-class city for allergy sufferers in Spring. So, why did the folks from KVIE and KXTV endorse the TV5?
 

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JNinCA:


The power limit is actually 160 kW at a height of 305 meters. As height goes up, power must come down to compensate. At 610 meters (2000 feet) the power limit is 30 kW.


Both stations are actually authorized to operate at power levels slightly higher than the FCC limit. KXTV is currently operating below that number since they don't yet have all the necessary gear to make the power they're allowed, but it's less than 3 dB below their fully-authorized power, so I doubt it will make too much difference for most people.


- Trip
 

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Quote:
Originally Posted by KG7OR /forum/post/16720712


....Lastly, both stations confirmed that they are at max transmitter power and their final antenna position on the tower, although the KVIE guy was strangely evasive when I asked him if any subsequent changes were in the works.....
Quote:
Originally Posted by JNinCA /forum/post/0


....Let's flesh out what "max" means. The FCC limit for VHF DTV is 160000 watts in Zone II. These two are nowhere close to that. They are at the max output of the transmitter they bought. They could hook up a second transmitter to double output if they could afford it. KVIE cannot. However, I still expect that to be the long term solution.

What I meant by max power is that the 2 stations are operating at the final power level and antenna position that they presently intend. They are not in an intermediate state with transmitter or antenna, like KCRA. This was an important question because the VHF issue could be improved if they were planning to boost their ERP or lift their antenna. Neither is in the works.
 

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Quote:
Originally Posted by deltaguy /forum/post/16723180


EV didn't test the TV5 for VHF. A really directional antenna can be completely foiled by trees, there's lots of them in Sacramento. It's a world-class city for allergy sufferers in Spring. So, why did the folks from KVIE and KXTV endorse the TV5?

They didn't. It's just what KVIE lashed up for the demonstration. The intent was to show that traditional rabbit ears antennas basically don't cut it any more, while a number of indoor antennas of better design can be quite satisfactory (witness Bob Hess' experience in his office, for example).


Reading the on-line reviews of the Terk 5, it appears to be better than most on VHF, and not quite as good as a Silver Sensor or HDTVa on UHF. So, with good VHF performance, it was a logical choice for KVIE.


BTW, Mike (?), KXTV engineer, did a great job of explaining the advertising on the cartons from a couple of indoor "HDTV" antennas that some of the audience had brought. Mike was a great public speaker--his discussion on this subject included frequent uses of "baloney," "marketing hype," and "not true." Good for him.


--Ron
 

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KXTV is presently operating at 22kW ERP with the transmitter making just under 6kW. The transmitter specified maximum output power is 8kW and KXTV has applied to the FCC be able to raise the transmitter power to all it will make. This is an increase of only 1.25dB! To make more power will require another amplifier cabinet added to the transmitter. This is not in the plans at this time. There was confusion with the FCC and the corporate attorney as to what power KXTV was operating at. This is not much of a surprise given all the now empty desks at KXTV. The guy that was chief engineer and dealt with this stuff quit a while back and is not being replaced. What remains of the maintenance engineering staff are just trying to keep it on the air at this point.


The FCC initially set the power levels stations were to operate at by picking a power that their calculations showed would give the same coverage as the existing analog transmitter. That is where the 22kW number came from.


If anybody knows of an indoor antenna that works well at VHF as well as UHF I am sure they would like to know what it is. They have gotten many phone calls complaining about lack of reception after the switch to VHF. A majority are from people in apartments or similar situations that can not put up an outside antenna. Several have been from people that were sold "HDTV" antennas that disconnected their outside antenna and hooked up what they were sold. Obviously they have been told to hook the outside antenna back up! The calls are tapering off but still coming in. Some people called the FCC and were told that stations were still making adjustments and things would get better which may be true in a few cases but not here.


The new side panels on news shows were at the behest of the Gannett manger in charge of all of the TV stations. He came to visit today and they got them on the air before he arrived. HD news is still being talked about but not in the plans at this time.
 

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Quote:
Originally Posted by Rory Boyce /forum/post/16728692


The new side panels on news shows were at the behest of the Gannett manger in charge of all of the TV stations. He came to visit today and they got them on the air before he arrived. HD news is still being talked about but not in the plans at this time.

I don't mind the panels, but putting "HD" in there is disingenuous at best.
 

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Quote:
Originally Posted by DEEPFRINGEGUY /forum/post/16716156


They sent me an invite because I'm trying to get them to increase their signal back up 66% to what it used to be when they were on VHF-lo. I'm pretty sure that their lower signal is why I don't receive them now, but did on both analog and digital before... $800.00 donation probably helped too!

I doubt the FCC will alow KVIE any more power, especially with the Co-channel interference problems with KIXE.
 

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Quote:
Originally Posted by KG7OR /forum/post/16724582


What I meant by max power is that the 2 stations are operating at the final power level and antenna position that they presently intend. They are not in an intermediate state with transmitter or antenna, like KCRA. This was an important question because the VHF issue could be improved if they were planning to boost their ERP or lift their antenna. Neither is in the works.

Well, I'll list what I think is the current situation. Everyone, pipe in if you have more recent info.

KCRA: Still on the backup 1500' candelabra. Expected to be on the KCRA tower in Aug.
KVIE: The station confirmed they are finished.
KXTV. Kept the same antenna for digital. As noted above, applied to the FCC for an increase in output, but 1.25db is small.
KOVR: I believe they still have to raise the digital (25) antenna. Supposed to be done this Fall.
KSPX: AFAIK, they are finished.
KMAX: Last I heard, transmitter was at 93%. I don't know if the additional power will make a difference.
KTXL. Still doing work, so they will be boosting power in the future.
KQCA. AFAIK, they are finished.


This brings to mind what I saw during the US Open Monday. KCRA was running this service loss notice. Why run service loss PSAs after June 12th? The affected people can't see them.
 
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