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post #14971 of 15669 Old 04-18-2017, 04:55 PM
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Originally Posted by kkpm View Post
Hi,
Also, don't forget K03IC-D will also be locating on Sutro if I can find a full power that is going off the air to work with me.
Blessings,
Keith
Woo.... Lets not forget, that KCSO-LD 3 (full power?) will be moving to Walnut Grove. Blanketing most of the East bay with signal on RF 3
This will cause problems with the bay area on RF 3. Possibly even San Francisco.
So this makes KTVJ-4 the station to watch. The station with a large viewing area.
KCRA analog 3 was strong here, so that basically makes K03IC-D, invalid here, a lemon.
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What type of antenna would you use for channel 3 up there on Sutro?
Larry
Time will tell If you can get KCSO-LD 3, based on your reception of old analog KCRA analog 3 from Walnut Grove.
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Do you envision the K03IC antenna being at the top of the tower?

Chuck
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post #14972 of 15669 Old 04-18-2017, 05:06 PM
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Originally Posted by 888CALLFCC View Post
Woo.... Lets not forget, that KCSO-LD 3 (full power?) will be moving to Walnut Grove. Blanketing most of the East bay with signal on RF 3
This will cause problems with the bay area on RF 3. Possibly even San Francisco.
So this makes KTVJ-4 the station to watch. The station with a large viewing area.
KCRA analog 3 was strong here, so that basically makes K03IC-D, invalid here, a lemon.

Time will tell If you can get KCSO-LD 3, based on your reception of old analog KCRA analog 3 from Walnut Grove.


KCSO-LD has proposed a highly directionalized antenna pattern pointed west. Rabbitears.info has a nice Longley-Rice Map to show lack of interference to San Francisco, Oakland, and San Jose.


Eventually the goal is to move to ATSC 3.0. I'm thinking that it'd be nice to operate around 10.5 Mbps using QPSK carriers or around 12 Mbps with 16 QAM carriers. At the 10.5 Mbps rate, the required SNR is about 4 dB. This gives an 11 dB advantage over ATSC 1.0. Let's assume we have 10 Mbps to use at this lower data rate. Let's assume a 1080i HEVC encoded picture requires 2 Mbps. Then, I can have five 1080i sub-channels going. Or, I can have three 1080i sub-channels plus seven 480i sub-channels.


Blessings,
Keith

Last edited by kkpm; 04-18-2017 at 05:07 PM. Reason: typo
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post #14973 of 15669 Old 04-18-2017, 05:23 PM
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Originally Posted by kkpm View Post
KCSO-LD has proposed a highly directionalized antenna pattern pointed west. Rabbitears.info has a nice Longley-Rice Map to show lack of interference to San Francisco, Oakland, and San Jose.


Eventually the goal is to move to ATSC 3.0. I'm thinking that it'd be nice to operate around 10.5 Mbps using QPSK carriers or around 12 Mbps with 16 QAM carriers. At the 10.5 Mbps rate, the required SNR is about 4 dB. This gives an 11 dB advantage over ATSC 1.0. Let's assume we have 10 Mbps to use at this lower data rate. Let's assume a 1080i HEVC encoded picture requires 2 Mbps. Then, I can have five 1080i sub-channels going. Or, I can have three 1080i sub-channels plus seven 480i sub-channels.


Blessings,
Keith
Right now, K03IC-D is very weak here. No match to KTVJ.
It does not look good.
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post #14974 of 15669 Old 04-18-2017, 05:29 PM
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Originally Posted by 888CALLFCC View Post
Right now, K03IC-D is very weak here. No match to KTVJ.
It does not look good.
K03IC-D is so bad now, .... that it does not even come in on my battery tv outdoors..... poor.
KTVJ does. same location ? ... why ?
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post #14975 of 15669 Old 04-18-2017, 05:36 PM
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Originally Posted by kkpm View Post
KCSO-LD has proposed a highly directionalized antenna pattern pointed west. Rabbitears.info has a nice Longley-Rice Map to show lack of interference to San Francisco, Oakland, and San Jose.

I think you mean east. The antenna pattern they show in the Walnut Grove application is exactly the same as the one they're using now. I assume they're just going to take down the existing antenna and move it to Walnut Grove. It has very little power off the back and it'll be side mounted on the tower. I keep checking to see if KCSO has gone off the air but not so far.

I'll probably get more interference from K03IC if it's on Sutro Tower than anyone in the Bay Area would ever get from KCSO.

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post #14976 of 15669 Old 04-18-2017, 05:53 PM
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Originally Posted by kkpm View Post
Then, I can have five 1080i sub-channels going. Or, I can have three 1080i sub-channels plus seven 480i sub-channels.
That's a lot of blessings!

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post #14977 of 15669 Old 04-19-2017, 06:39 PM
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Originally Posted by 888CALLFCC View Post
K03IC-D is so bad now, .... that it does not even come in on my battery tv outdoors..... poor.
KTVJ does. same location ? ... why ?


Hi,


I was at Mt. Tamalpais today. I finally figured out what was wrong with the KTVJ antenna. I have two stacked cross-polarized antennas. Something is wrong with one of the lower bay antennas. Therefore, instead of using circular polarization, I reverted to slant polarization and used the good lower antenna and the matching upper one. This allows the gain from having a two bay antenna. I can see the 3dB improvement receiving the signal on Mt. Loma Prieta. Also, I can once again pick up KTVJ from the upper east corner of Santa Rosa on Calistoga Rd. on the Rincon grade. Also, it was strong when driving from the south of San Rafael all the way through the Novato Narrows.


I did also run the correction today for the K03IC-D exciter. The exciter is now reporting 33 dB MER. The K03IC-D transmitter is still down in power some. Can you pick it up now? It was pretty strong in San Rafael.


Blessings,
Keith
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post #14978 of 15669 Old 04-19-2017, 08:53 PM
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KTVJ 4 has the same signal strength of 23 to 24 dB SNR, but the quality reading on my HD Home Run receiver is better at 80%. It was 62%. It's giving me a good solid signal here.
K03IC is still right at the cliff edge of 14.5 to 15.5 dB SNR, and the quality is still hanging below the 50% level, so I get no picture.

Note that this is with my High VHF-UHF antenna combination as I don't have anything for low VHF.

Larry

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post #14979 of 15669 Old 04-19-2017, 09:32 PM
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Quote:
Originally Posted by kkpm View Post
Hi,


I was at Mt. Tamalpais today.
I did also run the correction today for the K03IC-D exciter. The exciter is now reporting 33 dB MER. The K03IC-D transmitter is still down in power some. Can you pick it up now? It was pretty strong in San Rafael.
Blessings,
Keith
Yes, ... they both come in now. K03IC-D has returned.

I did notice now at 9:30pm the sub channels 1-thru 4 slowly pixelate & macroblock. The other sub channels 5 thru 13 do not.
Same problem on channel 3 or 4.
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post #14980 of 15669 Old 04-20-2017, 03:03 AM
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I'm getting pretty much the same results as Larry for KTVJ and K03IC.

Using a rooftop Antennacraft Y10-7-13, my best read for KTVJ is 25 dB SNR and K03IC comes in at 15, sometimes 16 dB SNR.

For K03IC, I get audio and video but it's constantly breaking up and never solid.
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post #14981 of 15669 Old 04-20-2017, 06:58 AM
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Originally Posted by kkpm View Post
I was at Mt. Tamalpais today. I finally figured out what was wrong with the KTVJ antenna. I have two stacked cross-polarized antennas. Something is wrong with one of the lower bay antennas. Therefore, instead of using circular polarization, I reverted to slant polarization and used the good lower antenna and the matching upper one. This allows the gain from having a two bay antenna. I can see the 3dB improvement receiving the signal on Mt. Loma Prieta. Also, I can once again pick up KTVJ from the upper east corner of Santa Rosa on Calistoga Rd. on the Rincon grade. Also, it was strong when driving from the south of San Rafael all the way through the Novato Narrows.

KTVJ is 8-10 dB stronger than before. I'll check it a few times during the day.

Chuck
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post #14982 of 15669 Old 04-20-2017, 09:09 AM
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Originally Posted by Calaveras View Post
KTVJ is 8-10 dB stronger than before. I'll check it a few times during the day.

Chuck

Hi Chuck,


Wow! There should just be a gain of 3 dB from having two bays over one bay. Since the antenna is at a slant, then half the power is still in the vertical plane and half is in the horizontal plane, so you should only see another 3 dB gain if your antenna is slanted the same way. Otherwise, I could have had some sort of cancelling happening for the circular polarization or perhaps it was not quite balanced and was more elliptical with more power going to the vertical polarization.


Blessings,
Keith
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post #14983 of 15669 Old 04-20-2017, 10:56 AM
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Hi Chuck,


Wow! There should just be a gain of 3 dB from having two bays over one bay. Since the antenna is at a slant, then half the power is still in the vertical plane and half is in the horizontal plane, so you should only see another 3 dB gain if your antenna is slanted the same way. Otherwise, I could have had some sort of cancelling happening for the circular polarization or perhaps it was not quite balanced and was more elliptical with more power going to the vertical polarization.


Blessings,
Keith
All I can say is that it is quite a bit stronger than it was previously when we discussed this. It's still not as good as it was at one time but better than the last month or so.

Chuck
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post #14984 of 15669 Old 04-21-2017, 12:55 AM
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Interesting... no signal strength change here in SF on KTVJ, as I mentioned above... still 23 to 24 dB. Signal quality is better, though.

Larry

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post #14985 of 15669 Old 04-21-2017, 10:16 AM
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KGO repeater crazy multipath

The KGO RF35 repeater is crazy! My broad beam DB4e bowtie antenna aimed directly at Mt. Allison 16 miles away stopped receiving a usable signal at all for the past two days. The XG91 aimed 45 degrees to the west at Mt. Sutro still picked up RF35, with the usual frequent breakups - although still watchable. So I disabled KGO on the direct aimed antenna. This morning I checked again, and now I pick up RF35 on the direct pointed antenna without any breakups at all! Signal strength is the usual high 80% range, signal quality is mid 70%.

I wonder if they're doing any work on the transmitter? Could it be a situation where they're generating ridiculous multipath at the source by hiding the antenna behind a tower? I thought I read a comment that this was the situation.

How does it look to others in the area, and what is your azimuth to the transmitter? For me it is 16 miles 357 degrees. Weird.

Edit: Just to be clear, the signal on my direct aimed antenna has shown no breakups all day as of 4:15PM, after being completely bad for two days (checked both evenings about 7PM). Guess I should check again this evening.

Edit2: 7PM and signal quality is 50%, no picture.
Mt. Sutro antenna works, though.

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post #14986 of 15669 Old 04-22-2017, 08:30 AM
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The KGO RF35 repeater is crazy! My broad beam DB4e bowtie antenna aimed directly at Mt. Allison 16 miles away stopped receiving a usable signal at all for the past two days. The XG91 aimed 45 degrees to the west at Mt. Sutro still picked up RF35, with the usual frequent breakups - although still watchable. So I disabled KGO on the direct aimed antenna. This morning I checked again, and now I pick up RF35 on the direct pointed antenna without any breakups at all! Signal strength is the usual high 80% range, signal quality is mid 70%.

There's another possibility that no one has mentioned. KGO-LD on 35 is right next to KICU. I looked at your TV Fool report and I see that you have a 1 edge path to KGO-LD but LOS to KICU. There's a general rule that says that adjacent signals can't be more than 33 dB different in signal strength to receive the weaker station. TV Fool shows a Noise Margin of 62 dB for KICU and 22 dB for KGO-LD. That's 40 dB. The difference in power between the two stations is only 16 dB but the 1 edge path greatly attenuates KGO-LD. The KGO-LD antenna is 285' lower than the KICU antenna. You're in an unfortunate location for KGO-LD. It may be impossible to get reliable reception. There's nothing you can do to get reliable reception when you have a weak signal next to a strong signal.

KGO-LD has had some issues that affect everyone but I believe you have a unique issue unrelated to what everyone else has seen. The only real solution is put up a high VHF antenna and watch KGO on channel 7.

Chuck
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post #14987 of 15669 Old 04-22-2017, 08:46 AM
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KGO-LD has had some issues that affect everyone but I believe you have a unique issue unrelated to what everyone else has seen. The only real solution is put up a high VHF antenna and watch KGO on channel 7.

Chuck
Thanks for the explanation. That makes sense and probably why I never have any issues with KGO 7.1 or KICU 36.1 from my location in Evergreen.
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post #14988 of 15669 Old 04-22-2017, 02:51 PM
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Observations while scanning the band: Crazy conditions have been happening lately. The other night KOVR was coming in with a very strong signal while my antenna was pointed to the southwest, so it was either a reflection or coming off the backside of the antenna. KQCA disappeared a couple of days ago while the two VHF stations from Walnut Grove were booming in. Yesterday KVIE RF 9 was gone and KXTV RF 10 was just about making it while KQCA RF 46 was booming in at 25 dB. By the way, I haven't seen any sign of KMAX since last December when they changed antennas. KDTS, RF 8, Virtual 52-1, the very low power station from Mt. Diablo, used to come in quite regularly, but for the past couple of weeks the signal has been below the cliff edge. KCBA, RF 13, virtual 35.1, was booming in the other night with my antenna pointed at Walnut Grove. KCBA transmits form Fremont Peak down near Salinas.

My Sony TV is still having major problems with channel 40. The signal level has been much lower than normal lately, and with my XG91 pointed at Mt. San Bruno, just five miles away, it's only got a signal of 16 dB max. When it does come in, I'm still getting KPOP on that weird 40.769 sub-channel.

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post #14989 of 15669 Old 04-22-2017, 06:38 PM
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There's another possibility that no one has mentioned. KGO-LD on 35 is right next to KICU. I looked at your TV Fool report and I see that you have a 1 edge path to KGO-LD but LOS to KICU. There's a general rule that says that adjacent signals can't be more than 33 dB different in signal strength to receive the weaker station. TV Fool shows a Noise Margin of 62 dB for KICU and 22 dB for KGO-LD. That's 40 dB. The difference in power between the two stations is only 16 dB but the 1 edge path greatly attenuates KGO-LD. The KGO-LD antenna is 285' lower than the KICU antenna. You're in an unfortunate location for KGO-LD. It may be impossible to get reliable reception. There's nothing you can do to get reliable reception when you have a weak signal next to a strong signal.

KGO-LD has had some issues that affect everyone but I believe you have a unique issue unrelated to what everyone else has seen. The only real solution is put up a high VHF antenna and watch KGO on channel 7.

Chuck
I did not even think to check adjacent channel interference. Isn't there a government agency that licenses and assigns broadcast frequencies to prevent interfence issues? Indeed, KICU RF36 and KGO-LD are right next to each other in space, less than 2 miles apart - Monument Peak and Mt. Allison. And they are on adjacent frequencies as well. Wow.

As if that wasn't enough, KICU transmits at 740KW, while KGO-LD is a flickering match in the wind at 12.1KW. My particular situation one-edging KGO and not KICU may be the last straw for this reception issue. However, it would seem that KICU and KGO being physically close on adjacent RF channels transmitting at a nearly 30dB difference in power is a Bad Idea.

I did check the TVFool prediction against the tuner readings and am getting -7dBmv strength and 22dB SNR (after 12dB antenna gain and maybe 7dB of cable loss and tuner noise figure) from the DB4e pointed at KGO-LD, so definitely some degradation from predicted. Could be caused by adjacent channel interference as the 1edge loss is supposed to be predicted.

So yeah, KGO-LD is basically hopeless. I'll put up a 7 - 13 VHF antenna soon.

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post #14990 of 15669 Old 04-22-2017, 06:51 PM
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I did not even think to check adjacent channel interference. Isn't there a government agency that licenses and assigns broadcast frequencies to prevent interfence issues? Indeed, KICU RF36 and KGO-LD are right next to each other in space, less than 2 miles apart - Monument Peak and Mt. Allison. And they are on adjacent frequencies as well. Wow.

As if that wasn't enough, KICU transmits at 740KW, while KGO-LD is a flickering match in the wind at 12.1KW. My particular situation one-edging KGO and not KICU may be the last straw for this reception issue. However, it would seem that KICU and KGO being physically close on adjacent RF channels transmitting at a nearly 30dB difference in power is a Bad Idea.

KGO-LD is 18 dB weaker in terms of transmitted power and should be no problem adjacent to KICU if you have LOS to both. Most people do but you're in an unlucky location.

The FCC has strict rules regarding all this but low power stations are not protected like full power stations are. There's a similar situation between KTVU-LD on 48 and KSTS on 49.

Chuck
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post #14991 of 15669 Old 04-22-2017, 06:57 PM
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By the way, I haven't seen any sign of KMAX since last December when they changed antennas.

You won't have any chance of seeing them until they move to the new antenna on the KOVR tower. I expect KMAX will be very similar to KOVR. Bob said he expects this to happen by the beginning of summer.

It wouldn't surprise me if they install a transmitter and an antenna that can also operate on channel 24 so the repack switch would be a piece of cake.

Chuck
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post #14992 of 15669 Old 04-23-2017, 02:07 PM
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Originally Posted by lifespeed View Post
I did not even think to check adjacent channel interference. Isn't there a government agency that licenses and assigns broadcast frequencies to prevent interfence issues? Indeed, KICU RF36 and KGO-LD are right next to each other in space, less than 2 miles apart - Monument Peak and Mt. Allison. And they are on adjacent frequencies as well. Wow.

As if that wasn't enough, KICU transmits at 740KW, while KGO-LD is a flickering match in the wind at 12.1KW. My particular situation one-edging KGO and not KICU may be the last straw for this reception issue. However, it would seem that KICU and KGO being physically close on adjacent RF channels transmitting at a nearly 30dB difference in power is a Bad Idea.
Yes, the agency is called the "FCC" but they focus on Janet Jackson's boob and selling off the "public" airwaves to the highest private bidders. Most of their technical assertions for digital TV have been errant nonsense for years apparently designed to destroy the broadcast television industry in support of mission priority #2.

I think KICU is licensed to go to 2000KW, so if that's the problem it could get even worse.

Here's even worse news: I do know some people with VHF antennas in some parts of San Jose that can't get the Sutro or San Bruno VHF stations. Why I do not know (it doesn't make any sense), but I just thought I'd point that out. I myself pick up those stations on a home-made coat-hanger wire dipole cut to around channel 7, installed in a second-story attic, and they are my strongest most reliable stations (except during the occasional interminable "maintenance" of Sutro), so your mileage may vary...

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post #14993 of 15669 Old 04-23-2017, 05:14 PM
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Quote:
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Yes, the agency is called the "FCC" but they focus on Janet Jackson's boob and selling off the "public" airwaves to the highest private bidders. Most of their technical assertions for digital TV have been errant nonsense for years apparently designed to destroy the broadcast television industry in support of mission priority #2.

I think KICU is licensed to go to 2000KW, so if that's the problem it could get even worse.
1) The FCC power limit is 1000 kW, so you think incorrectly. A check of the FCC database indicates no increase beyond the current 550 kW is authorized.

2) While the FCC does offer protections for stations, a) LPTV stations do not receive the same levels of protection as full-power or Class A stations, a condition of their licenses, and b) if any station chooses to accept additional interference for whatever reason, then that's on them. (Remember, KICU and KFSF were there first.)

- Trip

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post #14994 of 15669 Old 04-24-2017, 01:18 PM
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Originally Posted by lifespeed View Post
How does it look to others in the area, and what is your azimuth to the transmitter? For me it is 16 miles 357 degrees. Weird.
My TV Fool report shows LOS to both Sutro and Mt. Allison, but I'm still getting the breakups on RF35. My distance is 18.5 miles at 354 degrees. I used to get 7.1 OK a few months ago, but now it frequently drops out almost completely. I have a Clearstream 5 for the VHF at Sutro and a DB2e for the UHF at Allison. The signal strength for 35 is always strong (at least 80%) and signal quality is always 100%. But still the problem persists. To get 7.1, I was thinking of moving the antenna rig from my chimney mount to a 20' mast higher on the roof. But then that would mean extending the coax cable with a preamp, which might introduce other problems.
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post #14995 of 15669 Old 04-24-2017, 02:38 PM
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My TV Fool report shows LOS to both Sutro and Mt. Allison, but I'm still getting the breakups on RF35. My distance is 18.5 miles at 354 degrees. I used to get 7.1 OK a few months ago, but now it frequently drops out almost completely. I have a Clearstream 5 for the VHF at Sutro and a DB2e for the UHF at Allison. The signal strength for 35 is always strong (at least 80%) and signal quality is always 100%. But still the problem persists. To get 7.1, I was thinking of moving the antenna rig from my chimney mount to a 20' mast higher on the roof. But then that would mean extending the coax cable with a preamp, which might introduce other problems.
Good info. Your noise margin on RF35 is 20dB better than mine, yet still it is problematic. All I can suggest (I'll probably do this myself) is a real, directional, high-gain VHF Yagi like Stellar Labs 30-2476 combined with a good UVSJ like the one from Antennas Direct. I believe directivity is helpful for the combined benefits of increased gain with reduced sensitivity to off-axis multipath. Your Clearstream 5 VHF/UHF is broad beam and low gain. Judging by my experience with a broad beam UHF antenna, the DB4e, I have not found wide beam width to be at all helpful in the Bay Area with tightly-grouped transmitters and multipath problems.

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post #14996 of 15669 Old 04-24-2017, 04:54 PM
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Good info. Your noise margin on RF35 is 20dB better than mine, yet still it is problematic. All I can suggest (I'll probably do this myself) is a real, directional, high-gain VHF Yagi like Stellar Labs 30-2476 combined with a good UVSJ like the one from Antennas Direct. I believe directivity is helpful for the combined benefits of increased gain with reduced sensitivity to off-axis multipath. Your Clearstream 5 VHF/UHF is broad beam and low gain. Judging by my experience with a broad beam UHF antenna, the DB4e, I have not found wide beam width to be at all helpful in the Bay Area with tightly-grouped transmitters and multipath problems.
Huh...Antennas Direct claims the Clearstream 5 is "extreme range" VHF/UHF. I'm not technically proficient with the jargon, so that's not high-gain? And I thought at the time that a wide reception angle would be beneficial, but now I see that might have been a mistake. I forgot to mention, I have one of those Antennas Direct combiners (or a similar precursor). I'm going to try temporarily disconnecting the Clearstream and see if I get RF35 better just to eliminate the possibility of some kind of weird interactions between the 2 different antennas.
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post #14997 of 15669 Old 04-24-2017, 05:28 PM
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Huh...Antennas Direct claims the Clearstream 5 is "extreme range" VHF/UHF. I'm not technically proficient with the jargon, so that's not high-gain? And I thought at the time that a wide reception angle would be beneficial, but now I see that might have been a mistake. I forgot to mention, I have one of those Antennas Direct combiners (or a similar precursor). I'm going to try temporarily disconnecting the Clearstream and see if I get RF35 better just to eliminate the possibility of some kind of weird interactions between the 2 different antennas.
There is marketing, and then there are hard specs. Really only the latter is useful. The Clearstream 5 might be good for some applications, but it is not as high gain as the Stellar Labs linked above. It isn't nearly as large either. I think there is some segment of the market that doesn't like the aesthetics of the large, spindly "old-fashioned" looking antennae. But they do perform well for all their ugliness

That said, if you are combining two antennae using a broadband power splitter/combiner (post the model, part number and even a picture) then very likely that is causing you trouble due to destructive interference of signals on the same frequency from two antennae. The correct way to combine VHF and UHF is a diplexer, which combines the low frequency from one antenna with high frequencies from another. This avoids the destructive interference issue. Before changing any hardware this merits some checking. Could be an easy fix.

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post #14998 of 15669 Old 04-24-2017, 08:36 PM
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That said, if you are combining two antennae using a broadband power splitter/combiner (post the model, part number and even a picture) then very likely that is causing you trouble due to destructive interference of signals on the same frequency from two antennae. The correct way to combine VHF and UHF is a diplexer, which combines the low frequency from one antenna with high frequencies from another. This avoids the destructive interference issue. Before changing any hardware this merits some checking. Could be an easy fix.
The combiner I'm using came in the same order for my two antennas from Antennas Direct. I'll have to check the model, but it looks identical to the one in your link. But now I'm wondering if trying to combine UHF from 2 different antennae is a problem. Some more experimenting is in order tomorrow. I don't think the problem with RF35 will go away unless KGO changes their repeater location or increases the signal output, but maybe I can get 7.1 to work consistently again. BTW, thanks for all your insight. It's given me some ideas.
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post #14999 of 15669 Old 04-24-2017, 08:58 PM
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But now I'm wondering if trying to combine UHF from 2 different antennae is a problem.
If you're using the UHF to VHF Signal Joiner (UVSJ) then you are not combining UHF antenna, presuming you have the ports hooked up correctly.

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post #15000 of 15669 Old 04-25-2017, 03:35 PM
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All I can suggest (I'll probably do this myself) is a real, directional, high-gain VHF Yagi like Stellar Labs 30-2476 combined with a good UVSJ like the one from Antennas Direct.
Not sure if there's a difference with what I have and the one in the link. Model #s are almost the same. Mind has an "S" at the end and the other has a "Z". In trying different configurations I discovered water inside the grommet on the Clearstream connector. When I disconnected the DB2e to islolate the Clearstream to see if it would improve VHF from Mt Sutro, it was a complete failure. So I reconnected everything through the combiner like before and now virtually no VHF at all. UHF is a little worse with just the DB2e though. I think water did something to the electronics inside the Clearstream box where the coax connects and my fiddling with it set it over the edge somehow. If I replace it with a VHF only antenna, I may have to also get something better for UHF.
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