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post #11521 of 12786 Old 11-29-2014, 09:52 AM
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Quote:
Originally Posted by Otto Pylot View Post
That's a distinct possibility but I don't see anything out of the ordinary in our house. I know someone else has complained about the same issue when watching KGO via Dish so this just gets curiouser and curiouser.

I had a few days of very poor conditions this past week to Mt. Sutro during the period of high pressure but I didn't see anything on KGO that I could attribute to anything but poor conditions. Now that we're in the middle of a storm KGO looks to be back to normal. I'll keep an eye on it.

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post #11522 of 12786 Old 11-30-2014, 12:05 AM
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Originally Posted by 888CALLFCC View Post
A "low tech" way to check reception of the Fremont Peak antenna farm stations from Salinas, ... is with your car radio,
Use 102.5 FM and/or 96.9 FM only.

Driving around, you will notice the cutoff hill areas and LOS locations
In San Francisco those frequency will flip/flop between Sacramento reception areas and Salinas depending on the location.

Mostly, on one side of San Bruno Mountain (South San Francisco) Grand Avenue, Hillside Blvd, Etc, .....is Salinas
on the other side, (Geneva Avenue, Alemany, Etc,) it's Sacramento.

Salinas reception over bay water, up to Rohnert Park, should be ideal, except for fading.
I took a listen to those two frequencies you mentioned here at home and I get stations from Sacramento and Woodland, which is up toward Sacto. On 96.9 I get KSEG, "The Eagle" in Sacramento and on 102.5 I hear KSFM from Woodland. There's nothing coming in from the south. San Bruno Mountain and the other hills to the southeast of me must be blocking signals. That's probably why I never see anything from the south on channel 8... plus I have KDTS from Mt. Diablo, virtual 52, coming in on 8.

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post #11523 of 12786 Old 11-30-2014, 07:02 AM
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LPTV KBTV 8.5 Sacramento should be showing the REV'N animated logo. The network launches at 2 pm Monday. No San Francisco affiliate yet.

http://www.revntv.com/

Wanting a strong FCC to say no to the Wireless lobby. Keep the tv broadcast band for ota television broadcasters.
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post #11524 of 12786 Old 11-30-2014, 07:17 AM
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Quote:
Originally Posted by rdvegas View Post
LPTV KBTV 8.5 Sacramento should be showing the REV'N animated logo. The network launches at 2 pm Monday. No San Francisco affiliate yet.

http://www.revntv.com/

It is on 8.7.

KBTV has added several channels. Here's the current line-up:

8.1 - Crossings
8.2 - ONTV4U
8.3 - SBN
8.4 - Bold TV
8.5 - Retro TV
8.6 - Hot TV
8.7 - Rev'n TV

Since moving to RF 27 I can receive it almost all the time even though it doesn't show up on my TV Fool report.

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post #11525 of 12786 Old 11-30-2014, 11:23 AM
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Quote:
Originally Posted by DeaneG View Post
In Cupertino, for the last two days, we have been seeing interference on KGO7-1 as well. It's a brief pixellation every minute or so. I am definitely on RF7, with 100% signal strength via a high vhf log periodic.
I saw some pixellation on RF7 yesterday morning, here in W San Jose, which is highly unusual since I switched out antennas a couple years back.
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post #11526 of 12786 Old 11-30-2014, 04:29 PM
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K03HY is the worst. Everything at that station is "messed up".
3-7 has a flashing prompt that says "freeze", and the whole set of channels have a blurry wavy pixelation problem.
Some of the worst I've seen on the air. Unwatchable.

Also QVC, on that station, is no match for QVC, on 65-6.
Picture quality, sound quality, color quality, volume level, aspect ratio, etc.
like watching video with a "dial-up" internet connection.

Last edited by 888CALLFCC; 11-30-2014 at 04:34 PM.
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post #11527 of 12786 Old 12-01-2014, 01:13 AM
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Quote:
Originally Posted by Larry Kenney View Post
Another note of interest... every night at 6:02 pm both KGO and KPIX get hit with interference on Dish.
just a second or two, but it's precisely at 6:02.

Larry
Checked KGO-7 OTA today 11/30 @ 6:02 pm .... and no problems with OTA... So this is a Dish network problem only.
No issues with any of the San Francisco Sutro tower stations .... for a long time.

But, if San Francisco gets 70 mph winds, power failure issues, and rain, ....... then I notice clicks, pops, kur-plunk sounds in the picture, and other issues.
Sometimes the whole tower goes down for like 1 to 2 minutes.
But it has been a few years since that has happened.
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post #11528 of 12786 Old 12-01-2014, 07:26 AM
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Quote:
Originally Posted by 888CALLFCC View Post
K03HY is the worst. Everything at that station is "messed up".
KFTY has no programming this morning even though the SNR is 21 dB. Every sub channel is a black screen. There must have been a failure. Inversions messing with the link are unlikely right now.

Chuck
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post #11529 of 12786 Old 12-01-2014, 05:17 PM
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Quote:
Originally Posted by Calaveras View Post
KFTY has no programming this morning even though the SNR is 21 dB. Every sub channel is a black screen. There must have been a failure. Inversions messing with the link are unlikely right now.

Chuck
Looks like subchannels 5 through 8 have been dumped here. 1 through 4 only work now.

Have not made any effort yet on KFTY-2 here to see if it will lock on.
I do see signal on RF-2 in Roseville, CA ... Most likely the same station.

Edit: 12/01 @ 9pm Now all sub channels are back 1 through 8

Last edited by 888CALLFCC; 12-01-2014 at 09:05 PM.
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post #11530 of 12786 Old 12-01-2014, 07:23 PM
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Quote:
Originally Posted by 888CALLFCC View Post
Have not made any effort yet on KFTY-2 here to see if it will lock on. I do see signal on RF-2 in Roseville, CA ... Most likely the same station.

Yes, it's your only choice in Roseville. A friend in Placerville says he receives it easily.

Chuck
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post #11531 of 12786 Old 12-02-2014, 12:56 AM
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Interesting information from the December, 2014, issue of the "VHF-UHF Digest", the monthly publication of the Worldwide TV-FM DX Association:

KAXT RF 42, Virtual channel 1, SF/San Jose, has been authorized a power increase from 12.2 to 15 kW ERP.

One Ministry station K02QQ RF 2, Monterey, has been changed to K05NA RF 5, with 700 watts ERP.

Nine applications for a new full-power station in Sacramento on channel 43 have been pending for some time. The Commission has dismissed all of them. The applicants:
•La Dov Educational Outreach
•Calvary Christian Center
•ESP Technology Community Broadcasters
•Rising Tide of Sacramento
•Family Stations
•KVIE
•Amazing Facts
•Grant Educational Foundation
•LeSea Educational Broadcasting of Sacramento

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Last edited by Larry Kenney; 12-02-2014 at 01:05 AM.
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post #11532 of 12786 Old 12-02-2014, 01:10 AM
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K03HY has been experiencing problems for quite some time. I've seen several times where there hasn't been any video on any of the sub-channels... just black. Other times the video is pixelating and breaking up really bad, and other times everything looks okay. The transmitter signal strength is constant, so it's a problem with the interconnecting signals not making it to the translator receiver. I've watched it go from solid picture to pixelation to black in the matter of a couple minutes, so the links are right on the edge.

I have to agree with Ben that the picture quality is pretty bad, some sub-channels worse than others, but I think some of the sub-channels are better now than they used to be... when they're there.

Ben... do a new scan. They have 9 sub-channels now on all of the One Ministry stations.

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post #11533 of 12786 Old 12-02-2014, 07:34 AM
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Quote:
Originally Posted by Larry Kenney View Post
Nine applications for a new full-power station in Sacramento on channel 43 have been pending for some time. The Commission has dismissed all of them. The applicants:
•La Dov Educational Outreach
•Calvary Christian Center
•ESP Technology Community Broadcasters
•Rising Tide of Sacramento
•Family Stations
•KVIE
•Amazing Facts
•Grant Educational Foundation
•LeSea Educational Broadcasting of Sacramento

Larry
SF

It's about time. The groups competing for RF 43 started the process long before the transition. I doubt the FCC wanted to grant a construction permit to anyone on RF 43 now that the auction is around the corner.

Chuck
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post #11534 of 12786 Old 12-02-2014, 09:19 PM
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Quote:
Originally Posted by Larry Kenney View Post
K03HY
Ben... do a new scan. They have 9 sub-channels now on all of the One Ministry stations.
Larry
Thanks .. watching 3-8 now .. some type of creature feature show.
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post #11535 of 12786 Old 12-05-2014, 07:02 AM
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Nominal Signals

Since the rain started signals have been at nominal levels. I haven't seen any more than a few dB of variation on any stations at any time of the day for days now. Temperature inversions seem to be mostly non-existent. This is a good time to evaluate what you can receive with nothing to help or hurt your reception.

About the only issues I've seen are a few dB weaker signals from some Walnut Grove stations when the vegetation get's wet. When it drys out they go back up again. More distant stations like Sutro, Fremont and Salinas are unaffected.

Chuck
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post #11536 of 12786 Old 12-05-2014, 05:27 PM
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Channel filters?

Does anyone know of inline devices I can put into a coax to block specific channels? Like kpix is channel 29 virtual channel 5 and I can put a filter to block only channel 5/29. I saw channel master use to make stuff like jointenna, but more like just a blocker of a specific channel and the rest of the channels would remain untouched.
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post #11537 of 12786 Old 12-05-2014, 06:56 PM
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Custom 30+ dB notch filters would run around $125-150 each.
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post #11538 of 12786 Old 12-06-2014, 12:07 AM
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Quote:
Originally Posted by Calaveras View Post
Since the rain started signals have been at nominal levels. I haven't seen any more than a few dB of variation on any stations at any time of the day for days now. Temperature inversions seem to be mostly non-existent. This is a good time to evaluate what you can receive with nothing to help or hurt your reception.
Chuck
Signals have been pretty steady here this past week, too. However, they have mostly been below what I consider "normal". The only stations that have been consistant from Walnut Grove are KMAX and KQCA, but both have been below normal levels. Both VHF stations and the rest of the UHF's have all been hovering around the cliff edge between 13 and 16 dB SNR, so haven't been good enough to watch. KEMO, KRCB and KTLN from up north have all been somewhat lower than "normal", too.

If this is the real normal, then I've been getting a lot of help from the atmosphere!

Larry

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post #11539 of 12786 Old 12-06-2014, 02:03 AM
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Quote:
Originally Posted by Larry Kenney View Post
Signals have been pretty steady here this past week, too. However, they have mostly been below what I consider "normal". The only stations that have been consistant from Walnut Grove are KMAX and KQCA, but both have been below normal levels. Both VHF stations and the rest of the UHF's have all been hovering around the cliff edge between 13 and 16 dB SNR, so haven't been good enough to watch. KEMO, KRCB and KTLN from up north have all been somewhat lower than "normal", too.

If this is the real normal, then I've been getting a lot of help from the atmosphere!

Larry
The atmosphere may be the cause. I've seen a drop in signal levels during rain here. Rain isn't, or hasn't been, normal for a long time here. You play the hand you're dealt. I've tested a new room indoors here lately with a Leaf. The only window looks directly into an evergreen. While I thought it would be a tough location, a single location/aim/height is working for all of Walnut Grove with KUVS as well. Instead of tough, the room is easier than all of the rooms others I've tested. Indoor reception is certainly unpredictable.
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post #11540 of 12786 Old 12-06-2014, 08:20 AM
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Quote:
Originally Posted by Larry Kenney View Post
If this is the real normal, then I've been getting a lot of help from the atmosphere!
I really do think that rain and lack of inversions does constitute "nominal" conditions. This is why one needs to have an antenna system that receives the stations wanted under those conditions. A little help from the atmosphere frequently occurs and is the reason you see so many reports complaining of poor reception during rain. Rain fade with satellite reception is a common experience and is mistakenly applied to poor OTA reception in the rain.

I've found that the atmosphere mostly helps on the Salinas and Fremont stations and mostly hurts on the Sutro and Walnut Grove stations.
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post #11541 of 12786 Old 12-06-2014, 08:33 AM
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Quote:
Originally Posted by Monte324 View Post
Does anyone know of inline devices I can put into a coax to block specific channels? Like kpix is channel 29 virtual channel 5 and I can put a filter to block only channel 5/29. I saw channel master use to make stuff like jointenna, but more like just a blocker of a specific channel and the rest of the channels would remain untouched.

What exactly are you trying to do? Tin Lee makes notch filters but a true single channel filter will be very expensive.

I have an issue here with the very strong KUVS on RF 18 and the weak KOFY on 19. KOFY is very hard to receive because of this. I'm using a notch filter on KUVS so it doesn't overload the TV but the filter isn't of much help with KOFY because KUVS bleeds energy into the bottom end of KOFY causing interference. I can post spectrum analyzer images if you want to see more.

Chuck
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post #11542 of 12786 Old 12-06-2014, 09:15 AM
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Just to block a specific channel. So it's called a notch filter? Someone earlier said around 125$? Where did you guys get them from.

Quote:
Originally Posted by Calaveras View Post
What exactly are you trying to do? Tin Lee makes notch filters but a true single channel filter will be very expensive.

I have an issue here with the very strong KUVS on RF 18 and the weak KOFY on 19. KOFY is very hard to receive because of this. I'm using a notch filter on KUVS so it doesn't overload the TV but the filter isn't of much help with KOFY because KUVS bleeds energy into the bottom end of KOFY causing interference. I can post spectrum analyzer images if you want to see more.

Chuck
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post #11543 of 12786 Old 12-06-2014, 09:34 AM
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Quote:
Originally Posted by Monte324 View Post
Just to block a specific channel. So it's called a notch filter? Someone earlier said around 125$? Where did you guys get them from.
Quote:
Originally Posted by Calaveras View Post
What exactly are you trying to do? ...

Chuck

Chuck is asking the real question, why do you think you need to block KPIX?


SHF
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post #11544 of 12786 Old 12-06-2014, 09:36 AM
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Chuck is asking the real question, why do you think you need to block KPIX?


SHF

KPIX is just an example I used. The question I asked is the question I asked. What is a device to block out specific frequencies. I got the answer: notch filter.
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post #11545 of 12786 Old 12-06-2014, 09:49 AM
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Originally Posted by Monte324 View Post
KPIX is just an example I used. The question I asked is the question I asked. What is a device to block out specific frequencies. I got the answer: notch filter.
Blocking any TV RF channel is so unusual and notch filters are so poor that they are not offered for sale, Same as the Jointenna, those that were sold before did not meet the requirements and were tried to be returned by so many purchasers. Company building them decided to go out of that market.

The question being asked is for information about your specific problem. That we may be able to help with.

SHF

Last edited by SFischer1; 12-06-2014 at 10:12 AM.
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post #11546 of 12786 Old 12-06-2014, 12:06 PM
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Originally Posted by Monte324 View Post
KPIX is just an example I used. The question I asked is the question I asked. What is a device to block out specific frequencies. I got the answer: notch filter.

I wouldn't use the word "block" here. A notch filter for a TV channel will reduce the strength of the station. In my example I use a channel 18 filter to reduce the strength by about 25 dB. This does not block out the channel. It just reduces the strength so that my TV isn't overloaded by one station.

I still have the same question. What exactly are you trying to do?

Chuck
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post #11547 of 12786 Old 12-06-2014, 12:36 PM
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Quote:
Originally Posted by Calaveras View Post
I wouldn't use the word "block" here. A notch filter for a TV channel will reduce the strength of the station. In my example I use a channel 18 filter to reduce the strength by about 25 dB. This does not block out the channel. It just reduces the strength so that my TV isn't overloaded by one station.

I still have the same question. What exactly are you trying to do?

Chuck
Reduce probably is adequate. I'm not trying to do anything. I just wanted to know the name of the device. I just want to see what is out there.

Does it slightly reduce the other frequencies like the ones near it or is it pretty good at isolating just the ones it is designed for?
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post #11548 of 12786 Old 12-06-2014, 12:39 PM
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Quote:
Originally Posted by SFischer1 View Post
Blocking any TV RF channel is so unusual and notch filters are so poor that they are not offered for sale, Same as the Jointenna, those that were sold before did not meet the requirements and were tried to be returned by so many purchasers. Company building them decided to go out of that market.

The question being asked is for information about your specific problem. That we may be able to help with.

SHF

I'm not trying to solve anything. I just wanted to know the name and read info about them.

When you say poor you mean they really didn't work and it was a good idea, but no one could really do it right? Like they didn't really reduce the specific frequency as much and reduced the others too much?
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post #11549 of 12786 Old 12-06-2014, 01:08 PM
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Quote:
Does it slightly reduce the other frequencies like the ones near it or is it pretty good at isolating just the ones it is designed for?
Even the very best notch filter will wipe out the adjacent channels on each side of the channel being suppressed. The lower the Q of the filter, the more it will attenuate additional adjacent channels (2nd, 3rd, etc).

That's why this is an exercise in detail, should it be necessary to actually do the job.
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post #11550 of 12786 Old 12-06-2014, 03:42 PM
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Quote:
Originally Posted by Monte324 View Post
Does it slightly reduce the other frequencies like the ones near it or is it pretty good at isolating just the ones it is designed for?
Attached is the trace of my channel 18 notch filter. I marked it up in Photoshop to show the channels. The Markers are at the channel boundaries so you can read the attenuation. Channels 17 and 19 are pretty much wiped out. Channels 16 and 20 are quite useable. The rest of the UHF band has a fraction of a dB insertion loss. This is what you get for $125. To steepen up the slopes you need to spend much more money and even then adjacent channels will be impacted. There's no such thing as a filter with vertical slopes.

KUVS on 18 has a 70 dB noise margin so notching it by 30 dB simply lowers the noise margin to 40 dB which is still a big number.

Chuck
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