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post #3901 of 10906 Old 01-30-2009, 12:42 PM
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Quote:
Originally Posted by GGSkater View Post

I reworked my uhfblogspot antenna -
Going to the longer 9" design (vs. the 7" design), I am able to pick up KNTV and the other 2 NBC stations.

I bet you're talking about NBC Weather Plus 11-2 and Universal Sports 11-3. Those are sub-channels of KNTV. All three channels are coming from the same transmitter. Many of the stations offer more than one sub-channel: 2, 4, 7, 9, 11, 20, 22, 26, 32, 36, 54, 60, 65, and 66. With digital they can fit a lot more into their 6 MegaHertz channel allocation than they could with analog.

Quote:
Originally Posted by GGSkater View Post

One thought I've had is that if I can get this to work, it might be an interesting volunteer project to help out the "elderly and the poor" that the news media talks about as having been sluggish getting the coupon. Do these reporters understand the extent of the "antenna issue"...that is, the previously fuzzy / snowy analog signal is often completely dark for some locations in digital?

I'm sure the stations know, and a few have aired half hour programs offering details on the conversion to digital... how to connect up your converter box, what to look for in a new digital TV, making sure you have the right antenna, etc. I've also noticed that the stations are now running special PSAs about making sure you have the right antenna.

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SF

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post #3902 of 10906 Old 01-30-2009, 12:51 PM
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Quote:
Originally Posted by DEEPFRINGEGUY View Post

Here's a nice CECB (coupon-eligible converter box) chart that you might find interesting. Maybe you already have a link to it on your site, I forget... but, it's worth mentioning again:

http://en.wikipedia.org/wiki/Comparison_of_CECB_units

I also have the Insignia (same as Zenith) and it's a much better box than some of the other brands out there. It also allows manual adding of channels in a way that is compatible with OTA antenna rotors.
- DFGY

Wow, that's quite a list! I hadn't seen it before. I didn't know that there were so many brands and models available.

I bought the Insignia because it (and the Zenith) was rated as having the best receiver sensitivity and because you can do an Add-Scan, where it doesn't wipe out the station list, and you can manually add stations, too. It's amazing how much better it is than any of the other receivers I have.

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SF

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post #3903 of 10906 Old 01-30-2009, 01:03 PM
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Quote:
Originally Posted by Calaveras View Post

Hi Larry,

Just a couple of notes. KSPX digital is on 48 so you probably can't get it because KSTS analog on Mt. Allison is too strong. Even though I'm mostly blocked to KSPX analog on 29 which transmits from near Placerville, it still causes interference to KPIX digital.

Maybe you're having trouble with KOVR 25 since KGO is on 24 and KTSF is on 26. Talk about a strong signal sandwich! Those will go away if we ever have the transition.

How about KXTV on 61? Any luck there?

Can you get KSBW 8? If so you might be able to get their digital channel when they switch to 8.

Has anyone noticed that KTNC digital 63 is off the air for like a week now? I wonder if they've gone off the air to finish installation of their channel 14 antenna? They're already strong here on 63 so I expect them to be really strong on 14.

Chuck

Yup, got the analog - digital channels backward for KSPX. It's 48-KSTS that's blocking it for me, not KPIX.

Good point about KOVR being squeezed by KGO and KTSF, however I can get kTXL on 55, which is next to KTVU on 56. Maybe it's due to KTEH being so weak on 54 here. We'll see what happens after the transition. KOVR is going up to 1000 kW, too, so that should help.

I get KXTV on 61 occasionally, but it's not as strong as KMAX, KVIE, or KTXL here. It, KCRA on 35 and KQCA on 46 are all about the same strength. I get them occasionally, but not consistently like the others.

The only time I can get KSBW is when BOTH KGO and KQED analog are off the air... which is very seldom. Maybe when KQED gets off 9 and KGO goes digital, I'll have better luck. I don't get anything out of KCBA on 13, probably due to KNTV on 12.

I've also noticed that KTNC has been off the air. I don't know why, but it could be due to their installation of their antenna for channel 14. ? ? ?

Larry
SF

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post #3904 of 10906 Old 01-30-2009, 01:16 PM
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Quote:
Originally Posted by scottndsky View Post

I've only recently installed a CM4228 in San Jose, and ... I'm able to pick up the following (in order of virtual channel):

KTVU (56)
KRON (57)
KPIX (29)
KGO (24)
KQED (30)
KNTV (12)
KDTV (51)
KOFY (19)
KRCB (23) hit-or-miss
KTSF (27)
KMTP (33)
KICU (52)
KCNS (39)
KBCW (45)
KSTS (49)
KTEH (50)
KCSM (43)
KKPX (41)
KFSF (34)
KTLN (47) on occasion

Granted, several of those are non-English stations I won't be watching anyway. However, counting all of them, 20 digital stations with a 4228 is more than I had hoped for. I'm quite pleased with it.

I'm curious why your 4228 won't pick-up both KGO on 24 and KPIX on 29 without rotating it? They're both coming from Sutro, right?

Also, what are the 11 stations you're pleased about getting with your SR-15 locked down?

Regards,
Scott

You're 4228 is working very well for you, Scott. You're getting all of the stations from Sutro Tower (see below), Mt. San Bruno (11, 26 and 65) and the hills above Fremont (14, 36, 48 and 54) as well as Novato (47) and Cotati - Mt. Sonoma (23). The only ones you're missing are the two stations on Mt. Diablo (42 and 64 which are both in Spanish). You shouldn't have any problem with KGO when they move to channel 7, either. Several people in the South Bay with 4228's reported getting the station very strong when they did their overnight testing on channel 7 a while back.

I think my problem with the 4228 and the Sutro stations is due to multipath. I'm only 3/4 of a mile from the tower, so signals are strong and bouncing off other hills, buildings, trees, you name it. Different channels on different frequencies reflect differently, so that causes the problems.

The 11 stations I get with the SR-15 are the 11 on Sutro: 2, 4, 5, 7, 9, 20, 32, 38, 44, 60, and 66.

Larry
SF

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post #3905 of 10906 Old 01-30-2009, 01:25 PM
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Quote:
Originally Posted by bettygunn View Post

1) I currently can pick up ch. 8, 28, and 40 analog with my antenna in fremont and was wondering since 8 is based santa cruz way and 28 and 40 are called low power does that mean they wont reach fremont when they go digital because of what is called the cliff effect?

Chuck answered your questions, but I have a further comment on #1. Channels 28 and 40 are both analog low power stations transmitting from Mt. San Bruno, and they both have construction permits for digital stations. 28 has one for channel 24, but they have to wait for KGO to move to 7 before they go on the air. Channel 40 has one for channel 40, so they will go from analog to digital on the same channel at some point in the future. You should probably get both of them in Fremont.

Also, KAXT, a low power station on channel 22, has a construction permit for a digital station on channel 42. They will be moving from wherever they are now in the hills east of San Jose to Mt. San Bruno, too, so you should get that one, as well.

Larry
SF

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post #3906 of 10906 Old 01-30-2009, 01:30 PM
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Quote:
Originally Posted by DEEPFRINGEGUY View Post

Maybe we can get Larry to buy one of the new ones [new 4228] and tell us how good it is?

I think I'm done with antenna installation for a while. I'm getting too old for climbing around up there on the roof... plus I've got a good Hi-VHF antenna, an Antenna Craft Y-10-7-13, up there for VHF.

I'll try to get a couple pics of my "antenna farm" and post them, and will post a link here.

Larry
SF

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post #3907 of 10906 Old 01-31-2009, 12:28 PM
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Hi, looking for suggestion for a good indoor antenna. I live on the 3rd floor of an apartment building in Belmont, CA and all the windows face southwest. I would like to get at least the ABC and FOX channels.
I've attached the TVfool results. Thanks a lot!
LL
LL
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post #3908 of 10906 Old 02-02-2009, 07:45 AM
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Quote:
Originally Posted by Calaveras View Post

DFGY,

In order to clear the first ridge I'd have to be up at 105' and that's not going to happen. It's not the gain I need, it's the multipath rejection. The more antennas you phase the weaker the side lobes are.

I've been in the ham radio game for 40 years and there are always a few neighbors who hate antennas. I don't want to sound mean, but the only way I can deal with them is too ignore them. I have a ham friend who put up a 40' tower and the neighbor's wife was so distraught that they moved. I don't understand the "I hate antennas" mentality.

Even out here in a rural area on 10 acres with the nearest neighbor 400' away and the next two nearest 800' away, I'm still getting hints that they don't like antennas. I'm sorry people but there are no antenna ordinances in the county and no one has a right to a view.

If you saw the images I posted earlier, you can see the work platform just below the top of the tower. From there I can reach the antennas. I use a winch with wire rope to crank the mast down with the rotor removed to reach the top antennas. All of this is why I'll eventually switch to a crank-up tilt-over tower that allows access to the antennas while standing on the ground.

Chuck

Chuck,

Have you ever tried experimenting with "tilt angle?"
http://www.atechfabrication.com/prod...cal_tilter.htm

These add weight, but I'm real curious what one of these might do for me...

- DFGY
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post #3909 of 10906 Old 02-02-2009, 08:22 AM
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I seem to have lost KRONs traffic cams on 4-3 for some reason.
Is anyone else still getting these?

Thanks,
Scott
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post #3910 of 10906 Old 02-02-2009, 09:22 AM
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4-3 is gone here as well.

Bobby 

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post #3911 of 10906 Old 02-02-2009, 03:22 PM
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Quote:
Originally Posted by scottndsky View Post

I live in south San Jose near the intersection of Hwy 85 & 75 (Oakridge Mall).

I have a Omni-Directional FM antenna similar to this:


And I plan on getting a ChannelMaster CM4228 (the original version) to point towards Sutro Tower in S.F.

I'd like to understand how I should properly combine these together? Would a simple 3 dB splitter in reverse (combiner) do the trick?

Regards,
Scott

Just a follow up...

I didn't end up combining the FM with the CM 4228 as I originally planned. Instead, I ran a separate cable for each antenna. The 4228 goes to a 3dB splitter between my TV and my Tivo HD. The FM antenna goes directly to my old-school stereo receiver.

Pictures attached...

Regards,
Scott
LL
LL
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post #3912 of 10906 Old 02-02-2009, 05:43 PM
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Quote:
Originally Posted by scottndsky View Post

Just a follow up...

I didn't end up combining the FM with the CM 4228 as I originally planned. Instead, I ran a separate cable for each antenna. The 4228 goes to a 3dB splitter between my TV and my Tivo HD. The FM antenna goes directly to my old-school stereo receiver.

Pictures attached...

Regards,
Scott

Nice little setup there Scott! No amplifier?

I think you did the right thing by not combining the two. I just got through raising my FM antenna up to 19' this afternoon. At 8' KDFC was in/out of HD)) and analog. Now it's solid HD)).

If you find that you want to increase your db's a little bit more, try replacing your coax with LMR-400-75. It makes a big difference over RG-6 and a significant difference over RG-11.

- DFGY
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post #3913 of 10906 Old 02-02-2009, 07:57 PM
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Quote:
Originally Posted by DEEPFRINGEGUY View Post

Chuck,

Have you ever tried experimenting with "tilt angle?"
http://www.atechfabrication.com/prod...cal_tilter.htm

These add weight, but I'm real curious what one of these might do for me...

- DFGY

I tried it as an experiment once and it made no difference. I suspect in the majority of cases it won't make any difference since the signal is coming in at close to 0 degrees. If you look at the vertical pattern for the CM-4228 here:

http://www.hdtvprimer.com/ANTENNAS/cm4228.html

you'll see the antenna needs to be tilted up about 8 degrees to see 1 dB difference in the gain. It seems pretty unlikely that the signal would ever be coming from more than 8 degrees in elevation unless you live right under the tower.

I can tell you that this tilt device doesn't exist in ham radio. If it made any difference everyone would be using it.

There is one exception I knew about. About 20 (?) years ago I heard that K6QXY who lived in the north bay somewhere and had a huge array on 50 MHz had the ability to tilt his antennas down a little under the theory that would allow his main lobe to be put right at 0 degrees compensating for ground effects that raise the lobe. But this was for ionospheric propagation, not ground wave. I remain a bit skeptical that it did anything.

At UHF frequencies, even at only roof level, the antenna is so far above the ground in terms of wavelengths that I doubt the ground has any noticeable effect in raising the antenna main lobe.

Chuck
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post #3914 of 10906 Old 02-02-2009, 09:01 PM
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Quote:
Originally Posted by Calaveras View Post

I tried it as an experiment once and it made no difference. I suspect in the majority of cases it won't make any difference since the signal is coming in at close to 0 degrees. If you look at the vertical pattern for the CM-4228 here:

http://www.hdtvprimer.com/ANTENNAS/cm4228.html

you'll see the antenna needs to be tilted up about 8 degrees to see 1 dB difference in the gain. It seems pretty unlikely that the signal would ever be coming from more than 8 degrees in elevation unless you live right under the tower.

I can tell you that this tilt device doesn't exist in ham radio. If it made any difference everyone would be using it.

There is one exception I knew about. About 20 (?) years ago I heard that K6QXY who lived in the north bay somewhere and had a huge array on 50 MHz had the ability to tilt his antennas down a little under the theory that would allow his main lobe to be put right at 0 degrees compensating for ground effects that raise the lobe. But this was for ionospheric propagation, not ground wave. I remain a bit skeptical that it did anything.

At UHF frequencies, even at only roof level, the antenna is so far above the ground in terms of wavelengths that I doubt the ground has any noticeable effect in raising the antenna main lobe.

Chuck

Hi Chuck,

A-tech was talking about the Yagi style that we're using and the site mentions that if you have a horizontal stack, like you do, that the vertical and horizontal beamwidth is more narrow than a single 91XG, for instance; in theory making them more sensitive to tilt-angle.

Back when I was designing my new rig, I went out to this site and checked my location.
http://weltwireless.home.att.net/tec...alculator.html I'm not sure if I selected the options correctly, but it came back and said that for my latitude and longitude, I should tilt downward 2 or 3 degrees for optimum signal. It seemed be able to factor in the curvature of the earth, etc. Is this all a bunch of hoowey?

- DFGY
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post #3915 of 10906 Old 02-03-2009, 08:55 AM
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Just FYI,

KGO (ch. 7) is supposed to run a DTV test this evening at 6:15pm.
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post #3916 of 10906 Old 02-03-2009, 09:00 AM
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Quote:
Originally Posted by DEEPFRINGEGUY View Post

Hi Chuck,

A-tech was talking about the Yagi style that we're using and the site mentions that if you have a horizontal stack, like you do, that the vertical and horizontal beamwidth is more narrow than a single 91XG, for instance; in theory making them more sensitive to tilt-angle.

Back when I was designing my new rig, I went out to this site and checked my location.
http://weltwireless.home.att.net/tec...alculator.html I'm not sure if I selected the options correctly, but it came back and said that for my latitude and longitude, I should tilt downward 2 or 3 degrees for optimum signal. It seemed be able to factor in the curvature of the earth, etc. Is this all a bunch of hoowey?

- DFGY

Hi DFGY,

I'm not sure exactly what that page is referring to. Looks like it might be wireless internet or something similar where the distances are usually short. In that situation with a high gain antenna on one end, like one of those 2.4 GHz dishes, tilting could be very important.

I tried plugging in numbers more typical for fringe area TV reception. I pretended I was out in the Sacramento Valley looking to receive Walnut Grove over flat terrain at long distances like 50 or 60 miles, using 2000' for the transmit antennas and 20-30' for the receive antenna. I get tilt angles less than 1 degree. Even two 91XGs are not that narrow. I find I need to move my antennas +/- 5 degrees to see any real change. Also I don't believe that horizontal stacking affects the vertical beamwidth. One needs to stack vertically for that.

Here's something that may be of interest, a distance to the horizon calculator:

http://newton.ex.ac.uk/research/qsys...ysics/horizon/

For a TV station with an antenna at 2000', the distance to the horizon is 55 miles. If your TV antenna is at 33' (10m) your distance to the horizon is 7 miles. If you add those together, that 2000' antenna appears to be sitting on the horizon at 62 miles. You can see how important it is for fringe area reception to not have any hills in the way.

I believe the best thing you can do is to get your antenna above the local ground clutter, mostly buildings and trees, and that will maximize the signal and minimize multipath problems. Much higher than that probably won't do much good unless you get high enough to peak over some distant hill or building.

The best situation of course for fringe reception is live on top of a hill. I've often said that KSBW 8 is one of the strongest analog stations here even though it is 116 miles distant. But with their antenna at 3437' and my antenna at 2640', the summed distance to the horizon is 135 miles so they're not below the horizon here! Only any intervening low ridges would cause a problem.

Chuck
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post #3917 of 10906 Old 02-03-2009, 09:06 AM
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Quote:
Originally Posted by DEEPFRINGEGUY View Post

Nice little setup there Scott! No amplifier?

I think you did the right thing by not combining the two. I just got through raising my FM antenna up to 19' this afternoon. At 8' KDFC was in/out of HD)) and analog. Now it's solid HD)).

Thanks! Nope, no applifier.

I haven't played around with HD radio. I hardly listen to radio at all at home. The FM antenna allows me to get something, rather than noting.

Quote:
Originally Posted by DEEPFRINGEGUY View Post

If you find that you want to increase your db's a little bit more, try replacing your coax with LMR-400-75. It makes a big difference over RG-6 and a significant difference over RG-11.

Thanks for the tip! I'm not familiar with this brand. About 1/3 of my run is RG-6, but then both antennas tie into some existing RG-59 in my attic and walls.

I work with 75-ohm cable a lot at work - Mostly RG-6 and and a "Sub-Miniature RG-59" cable by Belden, similar to 1855A:
http://www.belden.com/pdfs/03Belden_...ial_Cables.pdf

I'll take a closer look at LMR-400-75 next time I need to buy some cable.

Thanks,
Scott
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post #3918 of 10906 Old 02-03-2009, 10:11 AM
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Quote:
Originally Posted by Calaveras View Post

Hi DFGY,

I'm not sure exactly what that page is referring to. Looks like it might be wireless internet or something similar where the distances are usually short. In that situation with a high gain antenna on one end, like one of those 2.4 GHz dishes, tilting could be very important.

I tried plugging in numbers more typical for fringe area TV reception. I pretended I was out in the Sacramento Valley looking to receive Walnut Grove over flat terrain at long distances like 50 or 60 miles, using 2000' for the transmit antennas and 20-30' for the receive antenna. I get tilt angles less than 1 degree. Even two 91XGs are not that narrow. I find I need to move my antennas +/- 5 degrees to see any real change. Also I don't believe that horizontal stacking affects the vertical beamwidth. One needs to stack vertically for that.

Here's something that may be of interest, a distance to the horizon calculator:

http://newton.ex.ac.uk/research/qsys...ysics/horizon/

For a TV station with an antenna at 2000', the distance to the horizon is 55 miles. If your TV antenna is at 33' (10m) your distance to the horizon is 7 miles. If you add those together, that 2000' antenna appears to be sitting on the horizon at 62 miles. You can see how important it is for fringe area reception to not have any hills in the way.

I believe the best thing you can do is to get your antenna above the local ground clutter, mostly buildings and trees, and that will maximize the signal and minimize multipath problems. Much higher than that probably won't do much good unless you get high enough to peak over some distant hill or building.

The best situation of course for fringe reception is live on top of a hill. I've often said that KSBW 8 is one of the strongest analog stations here even though it is 116 miles distant. But with their antenna at 3437' and my antenna at 2640', the summed distance to the horizon is 135 miles so they're not below the horizon here! Only any intervening low ridges would cause a problem.

Chuck

Thanks for the info. Chuck. You're a great resource!

That wasn't the only tilt-angle site that I used either; there was one that let you put in lat./long. coordinates.

I think you know where I'm going with all this inquiry. I just read a couple of articles at
the national DX site and they both confirm that stacking vertically can reduce or eliminate "airplane flutter." I might be getting a little closer to a solution

Here's one of them:
http://www.wtfda.org/images/stories/pdf/stagger.pdf


- DFGY
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post #3919 of 10906 Old 02-03-2009, 10:41 AM
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Quote:
Originally Posted by DEEPFRINGEGUY View Post

Just FYI,

KGO (ch. 7) is supposed to run a DTV test this evening at 6:15pm.

Are you sure about that? That's during their ABC 7 News at 6:00 p.m.

There's no mention of is here either:
http://abclocal.go.com/kgo/feature?s...nfo&id=6339723

Where did you learn about this? How long would it last? Would they actually turn off their analog transmitter on 7, turn off digital on 24, and fire up the digital on 7?

Regards,
Scott
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post #3920 of 10906 Old 02-03-2009, 11:05 AM
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Originally Posted by scottndsky View Post

Are you sure about that? That's during their ABC 7 News at 6:00 p.m.

There's no mention of is here either:
http://abclocal.go.com/kgo/feature?s...nfo&id=6339723

Where did you learn about this? How long would it last? Would they actually turn off their analog transmitter on 7, turn off digital on 24, and fire up the digital on 7?

Regards,
Scott

Yeah, I heard it this morning during the news. I usually don't catch these things at the time their happening, but I thought tonite I would tune in and see what it's all about. As far as how it works, I don't really know because I've never seen one of these tests, but I suspect that they'll flip 7 to digital for a few minutes... We'll see.

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post #3921 of 10906 Old 02-03-2009, 11:22 AM
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Last time they did a test like this in the Bay Area, it was during the news. They basically said something like "OK we're going to be doing the digital test now" and displayed info on the screen. On the digital channels, they put out a image saying "you're ready for the transition" and on the analog channels they put something like "you are not ready" and some URLs, IIRC.
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post #3922 of 10906 Old 02-03-2009, 11:36 AM
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Originally Posted by Xn0r View Post

Last time they did a test like this in the Bay Area, it was during the news. They basically said something like "OK we're going to be doing the digital test now" and displayed info on the screen. On the digital channels, they put out an image saying "you're ready for the transition" and on the analog channels they put something like "you are not ready" and some URLs, IIRC.

Yes, but *which* digital channels are we talking about? Will I need to "re-scan" for digital channels to insure I'm picking up 7.1, 7.2, and 7.3 on channel 7, rather than channel 24? Or will they display the "all good" on 24?

I'm primarily interested in my reception on 7 with my CM4228 UHF antenna.

Regards,
Scott
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post #3923 of 10906 Old 02-03-2009, 11:42 AM
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They are NOT doing a digital on channel 7 test tonight. It is the same test that that they have done in the past as mentioned above. It only lasts for about a minute. They do the digital on channel 7 tests infrequently and then they are at like 2 or 3 in the morning. I was involved with the first one several months ago, got out of bed and everything. I was able to receive the digital signal on channel 7 with my 4228 just fine.

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post #3924 of 10906 Old 02-03-2009, 11:49 AM
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Originally Posted by bobby94928 View Post

They are NOT doing a digital on channel 7 test tonight. It is the same test that that they have done in the past as mentioned above. It only lasts for about a minute. They do the digital on channel 7 tests infrequently and then they are at like 2 or 3 in the morning. I was involved with the first one several months ago, got out of bed and everything. I was able to receive the digital signal on channel 7 with my 4228 just fine.

Thanks for clarifying! I hope I'm able to report a similar success story with my 4228. I guess I'll have to wait and see...

Regards,
Scott
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post #3925 of 10906 Old 02-03-2009, 11:51 AM
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Quote:
Originally Posted by scottndsky View Post

Are you sure about that? That's during their ABC 7 News at 6:00 p.m.

There's no mention of is here either:
http://abclocal.go.com/kgo/feature?s...nfo&id=6339723

Where did you learn about this? How long would it last? Would they actually turn off their analog transmitter on 7, turn off digital on 24, and fire up the digital on 7?

Regards,
Scott

Here Scott. I guess I wasn't all that drowsy this morning when I heard it

Thank you for your e-mail. Yes it is at 6:15PM tonight.
Carol Mc Elroy
KGO-TV/DT ABC7

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post #3926 of 10906 Old 02-03-2009, 01:44 PM
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Originally Posted by DEEPFRINGEGUY View Post

Just FYI,

KGO (ch. 7) is supposed to run a DTV test this evening at 6:15pm.

This is just another one of those red screen NOT READY - green screen READY tests. They will NOT be testing the digital transmitter on channel 7.

It takes about five minutes for them to turn off the analog 7 and digital 24 transmitters, switch the antenna to the proper transmitter and turn the digital 7 transmitter on. Those tests have been done three times (maybe more) in the wee hours of Sunday morning from 2:35 to 6 am during their monthly transmitter inspection period. They won't be doing that tonight.

I don't know if other stations will also be doing the test tonight at 6:15. In the past it's been a coordinated community effort with most stations doing the test at the same time. The last time they did the test it was at 11:58 am and most stations participated.

Does anyone on here have cable service from a company other than Comcast, such as Alameda, places in Marin, Contra Costa, etc. to report on whether they get red or green? I know that Comcast, Dish and DirecTV are already using the digital signals and show the green READY slide during the tests. What about the others?

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post #3927 of 10906 Old 02-03-2009, 01:55 PM
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Quote:
Originally Posted by Calaveras View Post

For a TV station with an antenna at 2000', the distance to the horizon is 55 miles. If your TV antenna is at 33' (10m) your distance to the horizon is 7 miles. If you add those together, that 2000' antenna appears to be sitting on the horizon at 62 miles. You can see how important it is for fringe area reception to not have any hills in the way.
Chuck

Hills are the problem for lots of people here in the Bay Area. Mt. Tamalpais to the north, the East Bay Hills above Berkeley and Oakland, Mt. San Bruno and the coastal range to the south, are all causing lots of reception problems.

I think I'm lucky to get the Walnut Grove stations as well as I do since the signals have to get over the 1000' East Bay hills to get here. The transmitters are 62 miles from here and my antennas are about 35' above ground (315' above sea level), so using the calculations above, I'm within range, but then there's the negative impact of the hills. Is there a way to figure how much 1000 foot hills in the line of sight decrease range?

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post #3928 of 10906 Old 02-03-2009, 05:00 PM
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Quote:
Originally Posted by Larry Kenney View Post

Is there a way to figure how much 1000 foot hills in the line of sight decrease range?

This is the only information I know about on the subject:

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

If you know the elevation angle and distance to the hills, you can read the dB loss off the graphs. If the East Bay hills are 650' higher than you and say 10 miles away, the angle is 0.7 degrees.

Chuck
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post #3929 of 10906 Old 02-03-2009, 06:24 PM
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Originally Posted by scottndsky View Post

I seem to have lost KRONs traffic cams on 4-3 for some reason.
Is anyone else still getting these?

Thanks,
Scott

I dropped a note to KRON and got the following reply:

Quote:


… digital 4-3 is temporarily off the air due to equipment failure, and our engineers are working on it.
Thanks for watching Kron4 TV.

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post #3930 of 10906 Old 02-04-2009, 06:50 AM
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Quote:
Originally Posted by Xn0r View Post

Last time they did a test like this in the Bay Area, it was during the news. They basically said something like "OK we're going to be doing the digital test now" and displayed info on the screen. On the digital channels, they put out a image saying "you're ready for the transition" and on the analog channels they put something like "you are not ready" and some URLs, IIRC.

Well, I tuned in for the DTV test at 6:15pm on channel 7 last night. It turns out that they think I'm not ready... It seems kind of hokey to me. It appears to work just as you say. I was on channel 7 and got the "red" screen. Does this mean that if I was on
24 I would automatically get the "green" screen?

I happen to know that I am DTV ready, but I was just curious to see this DTV test that they've been doing periodically...

Well, I sent them an email and told them that I was confused about their test...


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