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San Francisco, CA - OTA - Page 135

post #4021 of 10449
What's interesting though is that all of the other stations broadcasting from Sutro seemed to come in just fine. Just KTVU was a problem. But I guess particular frequencies can be affected by conditions.

Interestingly, the day I did my scan, it was a cloudy, rainy day, and it was all fine. Today was sunny, and KTVU is still there. We'll have to see how it 'hangs' as weather, etc, changes over the next few weeks. But the signal strength meter during the scan showed a very strong signal, which didn't seem like a 'close to the edge' type of situation you describe. But perhaps these conditions have a much larger effect than I think (going from nearly 100% strength on the meter to very low, perhaps).
post #4022 of 10449
Quote:
Originally Posted by Larry Kenney View Post

Seems like KBSV's 421 watts is doing okay. They're up at 1888 feet, so that helps. Thanks for the report, Chuck.

You think KTNC on 14 is going to cause problems for them, Trip? We won't find out until June, since KTNC can't come up on 14 until KDTV analog goes off the air. Right now, KTNC-DT is off the air completely. They took their channel 63 transmitter off the air in January to move it out and make room for their new channel 14 transmitter, which they were going to have ready to go on Feb. 17, then Congress extended the transition date and they got screwed!

Larry
SF

Well, the difference is something like 20 dB, which isn't nothing. I really don't know for certain how much of an impact it will have, but this will be a good test.

- Trip
post #4023 of 10449
I still see KFTY off the air at 8AM this morning. Nothing on either 32 or 54.
post #4024 of 10449
I don't have any situations here where there is a very strong signal next to a weak one. I do have a few adjacent stations where the difference is 20-30 dB and I've not seen a problem with the weaker station. I'll bet there will be a problem if the difference rises to 50 dB. My real test will be after the transition when KUVS analog goes off of 19 and then I'll have the 500KW KUVS-DT on 18 only 14 miles away and KOFY on 19 at 110 miles. I'm wondering if I'll ever be able to receive KOFY.

I don't really expect a problem between KBSV and KTNC when they start up on 14 even with KTNC will be running 20dB more power. My highly directional antenna will take care of that. It may be different story for people out in the valley though.

The problem here is going to be KAZV and KICU both on 36 and 10 degrees apart. I may up receiving neither. There just doesn't seem to be any place where KAZV can go without a problem.

Chuck
post #4025 of 10449
Quote:
Originally Posted by bobby94928 View Post

I still see KFTY off the air at 8AM this morning. Nothing on either 32 or 54.

I checked this morning and they are on 32.3. What's weird is that their beam heading is about 7 degrees farther north now. When on 54 it was 183 degrees and now it's more like 190 degrees. The FCC says they should be 185 degrees. Initial indications are that their signal may be a few dB stronger but it'll take a few weeks of varying weather conditions to know that for sure.

I found out that "Adding Digital Channels" on my Sony will not remap stations that change sub-channels or completely change channels. Both 64 and 19 changed from .3 to .1 and now I have to tune to the real RF channel to get them. Entering 19.1 and 64.1 results in "No Signal." Same goes for KFTY now. I performed "Add Channels" but entering 50.1 still goes to RF 54. I suppose I'll have to do a scan from scratch but not until June 13th.

I just checked my DTVPal DVR and it handles these changes correctly. It automatically updated 19 and 64 last night showing "New Services Found" and this morning I manually added 32 and now entering 50 tunes to RF 32. Funny thing is though it calls it 71-1. This is not the first time I've seen that though.

Chuck
post #4026 of 10449
How could it be 32.3? Isn't it occupied by KMTP for both digital and analog?
post #4027 of 10449
Quote:
Originally Posted by pixelation View Post

How could it be 32.3? Isn't it occupied by KMTP for both digital and analog?

Yes, KMTP analog is on 32, digital on 33. As Larry pointed out most people in the Bay Area have no chance at KFTY until KMTP analog goes off. We were both surprised to see the FCC grant an STA to KFTY considering the coverage overlap. See my post #3973 on page 133 of this thread for a link to an image showing the overlap in coverage between KFTY, KMTP, and KION all on 32.

Chuck
post #4028 of 10449
Quote:
Originally Posted by Trip in VA View Post

Well, the difference is something like 20 dB, which isn't nothing. I really don't know for certain how much of an impact it will have, but this will be a good test.
- Trip

Something I hadn't thought much about, but I receive some distant channels that are adjacent to channels on Sutro Tower that's located just 3/4 of a mile from me. I get 23 that's 43 miles away to the north and 25 that's 62 miles away to the northeast on either side of KGO: KRCB 23, KGO 24, KOVR 25; 46 that's also 62 miles away to the northeast next to KBCW and KTLN that's 30 miles away to the NNW: KBCW 45, KQCA 46, KTLN 47 and 55, also 62 miles away to the northeast, next to KTVU and KRON: KTXL 55, KTVU 56, KRON 57.

It appears that local adjacent channels don't really bother that much! Maybe they reduce the distant signal some, but not enough to lose reception. I'm using a CM4228.

Larry
SF
post #4029 of 10449
Quote:
Originally Posted by Larry Kenney View Post

You guys down in the South Bay, Turbo and Xn0r, might also be close to that infamous cliff edge and you might be seeing the effects of the changing conditions right now.

There hasn't been a lick of rain here in Sunnyvale for over three days, so my personal "cliff edge" had more to do with the drips of water which came out of the matching transformer at the antenna when I took it down today. Here's the heart-stopping, edge-of-your-seat story...

I was comparing the signals today to what I "normally" get, and noticed that KRON was now at 0% signal. I was contemplating the theory that I had a problem with UHF, but it didn't completely add up. 44 had gone from 86% down to about 68%. But channel 54, which should have roughly the same signal strength where I live actually increased from 67% to 83%, and it's transmitter is over in Fremont, 90 degrees east of where my antenna is pointed, and 54 is even higher up in the UHF spectrum than 44. Normally, with my antenna left pointing toward Sutro, 54 over in Fremont was on the bad side of spotty, but when KTEH transmission began on 9-2, I just left 54 behind. But since most of my signals took a dump this last week, 54 miraculously increased in strength, with no break up. KICU also increased from 86% to 92%, and it's well up there in the UHF, too. So the notion my problem might be UHF-related had pulling my hair. Realizing that there's not much left up there to pull, I needed to find the answer before it was too late.

So, I figured I had to go through the motions of at least pulling the antenna down for a look-see before giving up. I just couldn't see anything wrong with the elements, nor did I see much that could go wrong with the front of the antenna. I examined the 300-75 ohm matching transformer. I was admiring my stellar job I had done at waterproofing the coax-to-transformer connection. Silicone around the coax, followed by heat shrink tubing and zip ties at each end. Then more silicone around that, then larger heat shrink tubing around the end of the transformer's shell and over the coax, followed by more zip ties at each end. I and my imaginary friend were nodding in unanimous approval, when I felt a drip of water come out the other end, where the 300 ohm flat lead enters the transformer's shell. Umm, well, it looked sealed from the factory, so I had completely ignored that end! But what looked sealed was simply a seam, and it was finally breached. I took the transformer off and puffed into the coax connector, and the fountains of Rome came spewing out the other end. The contact was rusty. The resistance measured anywhere between 13 ohms and 200 ohms, depending on how I pushed and pulled the lead. Do ya think, maybe...?

So I installed a good used transformer and sealed both ends, thank you very much, with coax seal this time. And of course, the new transformer solved the whole problem. But, now I am left with new confusion. Recall channel 36 and 54 that had miraculously increased in strength, while most others took a nose dive. With the installation of the new transformer, the signals on those two channels dropped back down to "normal." With the rusty transformer, 54 was barreling in at 83%, but with the new transformer, it's back down to 62% and spotty. Likewise, channel 36 loved the rusty transformer, with a signal of 92%, but dropped to 82% with the new transformer. Can anybody explain what strange things lurk in such a simple device that could cause such unexplainable behavior? And why did the analog signals seem to come through the crapped-out transformer normally?

Just FYI, the signals for all the channels I watch, before and after transformer replacement, were/are:
2: 33% & 92%
4: 0% & 79%
5: stayed at 100%
7: 79% & 92%
9: 87% & 92%
11: stayed at 100%
20: 83% & 86%
36: 92% & 82%
44: 68% & 100%
54: 83% & 62%

I have a question about exactly which element(s) on my antenna deal with UHF. I have the UHF/VHF combo, with the large section composed of many long elements arranged in a chevron pattern. At the other end are smaller elements arranged in a vertical fan tail configuration. Jutting out from the center of this fan tail is a horizontal piece with very small elements along it's length. And where all three of these different pieces come together, is a teeny bow tie element about as big as, well... a bow tie. Is this little bow tie element the only part that pulls in UHF, or do the vertical fan tail and horizontal sections on the rear also contribute to UHF reception? God, if it's just that puny bow tie element, I'm amazed I pull anything in, and can only imagine what I could get with a nice UHF antenna.
post #4030 of 10449
Quote:
Originally Posted by Calaveras View Post

I checked this morning and they are on 32.3. What's weird is that their beam heading is about 7 degrees farther north now. When on 54 it was 183 degrees and now it's more like 190 degrees. The FCC says they should be 185 degrees. Initial indications are that their signal may be a few dB stronger but it'll take a few weeks of varying weather conditions to know that for sure.

I found out that "Adding Digital Channels" on my Sony will not remap stations that change sub-channels or completely change channels. Both 64 and 19 changed from .3 to .1 and now I have to tune to the real RF channel to get them. Entering 19.1 and 64.1 results in "No Signal." Same goes for KFTY now. I performed "Add Channels" but entering 50.1 still goes to RF 54. I suppose I'll have to do a scan from scratch but not until June 13th.

I just checked my DTVPal DVR and it handles these changes correctly. It automatically updated 19 and 64 last night showing "New Services Found" and this morning I manually added 32 and now entering 50 tunes to RF 32. Funny thing is though it calls it 71-1. This is not the first time I've seen that though.

Chuck

Glad to hear the KFTY has moved successfully. Looks like they had some PSIP problems at first, but they seem to have it straightened out now if you can enter 50 and get RF32. Why it shows as 71-1 is really weird though! The different direction for picking up the signal is interesting.

My Sony acts the same way as yours, Chuck. Once you've done a scan, the tuner will add new stations by their transmitter channel number rather than the PSIP virtual channel number. I've found myself announcing problems with PSIP when it was actually my tuner that was screwing up.

PSIP is interpreted differently by the various tuners, and some settings work with some receivers but not all. Stations have to make sure things are exactly right for all tuners to work properly.

The tuner in the Insignia converter box seems to pick up all of the changes automatically on it's own. When stations add new sub-channels or it finds new stations it adds them using the PSIP channel number. It was interesting what happened when KGO did their digital test on 7. It added three new channels, 7-1, 7-2 and 7-3, for channel 7, and left the three that were already there for channel 24. When they went back to 24, it found the station there, leaving the other set for 7, so I had two 7-1's, two 7-2's and two 7-3's. A total re-scan deleted the set for channel 7.

Larry
SF
post #4031 of 10449
Quote:
Originally Posted by Turbo DV8 View Post

I have the UHF/VHF combo, with the large section composed of many long elements arranged in a chevron pattern. At the other end are smaller elements arranged in a vertical fan tail configuration. Jutting out from the center of this fan tail is a horizontal piece with very small elements along it's length. And where all three of these different pieces come together, is a teeny bow tie element about as big as, well... a bow tie. Is this little bow tie element the only part that pulls in UHF, or do the vertical fan tail and horizontal sections on the rear also contribute to UHF reception?

Congratulations on your trouble-shooting adventure, Turbo! I can't answer your question why the water affected some channels negatively (which makes sense to me) but caused others to increase. We'll leave that to some RF experts! At least you found your problem.

As for your antenna elements... the very long ones are for low VHF 2-6, the midsized ones are for high VHF 7-13 and that part jutting out from the center as well as the vertical fan tail and bow tie are for UHF 14-69. The various lengths are probably all mixed in together for VHF, but the UHF part on the front should be separate.

Larry
SF
post #4032 of 10449
Quote:
Originally Posted by Larry Kenney View Post

Something I hadn't thought much about, but I receive some distant channels that are adjacent to channels on Sutro Tower that's located just 3/4 of a mile from me. I get 23 that's 43 miles away to the north and 25 that's 62 miles away to the northeast on either side of KGO: KRCB 23, KGO 24, KOVR 25; 46 that's also 62 miles away to the northeast next to KBCW and KTLN that's 30 miles away to the NNW: KBCW 45, KQCA 46, KTLN 47 and 55, also 62 miles away to the northeast, next to KTVU and KRON: KTXL 55, KTVU 56, KRON 57.

It appears that local adjacent channels don't really bother that much! Maybe they reduce the distant signal some, but not enough to lose reception. I'm using a CM4228.

Larry
SF

Hmm. Well, it will be interesting to see what happens. I've heard stories about adjacent channel interference with digital, but it's not consistent. I'd wonder why.

- Trip
post #4033 of 10449
Quote:
Originally Posted by Larry Kenney View Post

For Patty's info, KFTY has been granted Special Temporary Authority (STA) to move to their post-transition channel. They're the only station in this area that has requested an STA so far.

Thanks for the update, Larry. I won't bother rescanning for KICU any time soon, then. :-)


Patty
post #4034 of 10449
Quote:
Originally Posted by Turbo DV8 View Post

But, now I am left with new confusion. Recall channel 36 and 54 that had miraculously increased in strength, while most others took a nose dive. With the installation of the new transformer, the signals on those two channels dropped back down to "normal." With the rusty transformer, 54 was barreling in at 83%, but with the new transformer, it's back down to 62% and spotty. Likewise, channel 36 loved the rusty transformer, with a signal of 92%, but dropped to 82% with the new transformer. Can anybody explain what strange things lurk in such a simple device that could cause such unexplainable behavior? And why did the analog signals seem to come through the crapped-out transformer normally?

As more of a digital guy, and a software guy than a hardware, and especially not an analog or RF guy, I refer to this sort of thing as PFM. (old military slang, AFAIK) :P
post #4035 of 10449
Our pursuit of DTV is reaching the "extreme measures" stage.
TVFool says we should have plenty of reception:

But TVFool does not take trees into account:

We can pick up about 8 analog stations, but no digital stations.
All the really strong stations are low VHF. High VHF is weak.
Analog UHF is unwatchable with a roof antenna.
The only way I could watch it at all was to hang a TV antenna
high up in the redwoods. After getting no signals from roof height,
I tried hanging it from the tree for digital.

The antenna is a 91XG, it is up 50'. There is 100' of new RG6U.
I aimed it carefully at Sutro Tower:


but it was all for naught:


Tried Channel Master and Zenith STBs. Tried with and without Antennacraft amplifier.
post #4036 of 10449
Quote:
Originally Posted by andytiedye View Post

Our pursuit of DTV is reaching the "extreme measures" stage.
TVFool says we should have plenty of reception:
But TVFool does not take trees into account:
We can pick up about 8 analog stations, but no digital stations.
All the really strong stations are low VHF. High VHF is weak.
Analog UHF is unwatchable with a roof antenna.

Your description sounds just like my experience with a friend in Arnold at 4200' but with a wall of pines across the street directly in the path to Walnut Grove. Your only hope would be to top one of the tallest trees and put the antenna up there. That works well for another friend in Placerville who otherwise would also be looking through a wall of pines.

Chuck
post #4037 of 10449
I have Comcast expanded basic cable and recently, maybe 3-4 days ago, I lost signal from Fox HD (Channel 2.1) and CBS HD (Channel 5.1). I'm not using a STB, it goes straight into my plasma. I've been rescanning channels everyday since with no luck. Has anyone else experienced this?
post #4038 of 10449
Quote:
Originally Posted by aerodynamics View Post

I have Comcast expanded basic cable and recently, maybe 3-4 days ago, I lost signal from Fox HD (Channel 2.1) and CBS HD (Channel 5.1). I'm not using a STB, it goes straight into my plasma. I've been rescanning channels everyday since with no luck. Has anyone else experienced this?

I think Comcast is moving more and more channels to the digital cable end, so you'll need a cable box to get a lot of them now. I was recently in a comcast office, and overheard one of the employees saying that some of the old, small non digital STBs which some were still using would stop working soon.
post #4039 of 10449
A rainy day is a good time to evaluate signals. KFTY is running about 6-8 dB stronger on 32 than they were on 54, SNR 24/25 vs SNR 17/18 under similar conditions. For digital that's a big difference.

The bad news is that KION and KFTY interfere with each other at times depending on ducting conditions. One can override the other or I can end up with neither. So far I have not seen both at the same time. Even with a pair of 91XGs and the two stations almost 90 degrees apart, there still isn't enough side rejection to completely isolate the two stations. I believe that would take >40 dB and that's asking a lot.

With analog 50 off the air, it seems I can receive KTEH-DT under a slightly poorer conditions now.

Chuck
post #4040 of 10449
It's interesting to see how much stronger KFTY is for you on 32 than it was on 54. They running less power now, 19.9 kW vs 30 kW, and didn't change antenna height, so the lower frequency must be working in their favor. Either that or it's the conditions.

Conditions have been changing quite a bit over the past few days here in San Francisco. A couple of days ago I was getting 6, 13, 31 and 58 from Walnut Grove, KRCB 22 from Sonoma Mt. and the four stations from the South Bay, 14, 36, 48 and 54, all solid. Today conditions were quite different. KMAX 31, which is usually solid here at 20 to 24 db SNR, was below the cliff edge at 14.5 dB, and all of the other Walnut Grove stations, plus KRCB and both KSTS and KTEH from the South Bay were out as well. It's the worst I've seen it in a long time.

This week, sometime after the rain moves out, I'm going to take my laptop with the analog and digital USB tuner and head north to see how far KMTP goes before I get KFTY. The two transmitters are only 65 miles apart, so somewhere around Novato I should be half way between them. Mt. Tam will probably shadow KMTP, so I might get KFTY before I get to Novato. I use a short mag-mount whip antenna, so it's completely omni-directional except for the effects of the car. Signal strength will determine which station I get. It's going to be interesting to see how the analog signal affects the digital and how the digital affects the analog. We'll see what happens.

Larry
SF
post #4041 of 10449
Quote:
Originally Posted by Larry Kenney View Post

It's interesting to see how much stronger KFTY is for you on 32 than it was on 54. They running less power now, 19.9 kW vs 30 kW, and didn't change antenna height, so the lower frequency must be working in their favor. Either that or it's the conditions.

Conditions have been changing quite a bit over the past few days here in San Francisco. A couple of days ago I was getting 6, 13, 31 and 58 from Walnut Grove, KRCB 22 from Sonoma Mt. and the four stations from the South Bay, 14, 36, 48 and 54, all solid. Today conditions were quite different. KMAX 31, which is usually solid here at 20 to 24 db SNR, was below the cliff edge at 14.5 dB, and all of the other Walnut Grove stations, plus KRCB and both KSTS and KTEH from the South Bay were out as well. It's the worst I've seen it in a long time.

This week, sometime after the rain moves out, I'm going to take my laptop with the analog and digital USB tuner and head north to see how far KMTP goes before I get KFTY. The two transmitters are only 65 miles apart, so somewhere around Novato I should be half way between them. Mt. Tam will probably shadow KMTP, so I might get KFTY before I get to Novato. I use a short mag-mount whip antenna, so it's completely omni-directional except for the effects of the car. Signal strength will determine which station I get. It's going to be interesting to see how the analog signal affects the digital and how the digital affects the analog. We'll see what happens.

Larry
SF

I can see the frequency change helping. Even in the world of analog I saw it first-hand. Where I live, I could see the analogs from Raleigh NC 24/7 up through 22, but 28 and above would vanish entirely during the day.

Any chance you can capture me some TSReader data on KFTY-DT and KRCB-DT and a few others that I'm missing or that otherwise might have changed since you last sent me data?

Your journey to the digital cliff sounds interesting and I can't wait to hear the outcome.

- Trip
post #4042 of 10449
Quote:
Originally Posted by Trip in VA View Post

I can see the frequency change helping. Even in the world of analog I saw it first-hand. Where I live, I could see the analogs from Raleigh NC 24/7 up through 22, but 28 and above would vanish entirely during the day.

Any chance you can capture me some TSReader data on KFTY-DT and KRCB-DT and a few others that I'm missing or that otherwise might have changed since you last sent me data?

Your journey to the digital cliff sounds interesting and I can't wait to hear the outcome.

- Trip

I'll get TSReader data for KFTY, KRCB and KTLN for you while I'm up north.

They say that it's supposed to be nice on Tuesday, so we'll try to head up there then.

Report to follow on how the two channel 32's compete with each other.

Larry
SF
post #4043 of 10449
Quote:
Originally Posted by Larry Kenney View Post

It's interesting to see how much stronger KFTY is for you on 32 than it was on 54. They running less power now, 19.9 kW vs 30 kW, and didn't change antenna height, so the lower frequency must be working in their favor. Either that or it's the conditions.

In their first application for digital 32, they showed an antenna with a pattern a bit more favorable for me than the channel 54 antenna. The result of that was going to be nearly identical ERP in my direction. But in their CP, their antenna pattern is identical to the channel 54 pattern. (Same antenna?) So the result is 1.8 dB less ERP in my direction.

Quote:


Conditions have been changing quite a bit over the past few days here in San Francisco. A couple of days ago I was getting 6, 13, 31 and 58 from Walnut Grove, KRCB 22 from Sonoma Mt. and the four stations from the South Bay, 14, 36, 48 and 54, all solid. Today conditions were quite different. KMAX 31, which is usually solid here at 20 to 24 db SNR, was below the cliff edge at 14.5 dB, and all of the other Walnut Grove stations, plus KRCB and both KSTS and KTEH from the South Bay were out as well. It's the worst I've seen it in a long time.

Same experience here. Reception has been what I call nominal. I think that most people (myself included) didn't realize how much of the time that the signals are getting a little help from ducting. I always thought of ducting as those major midwest ducts where you could receive stations hundreds of miles away that typically were nonexistent. I hadn't really considered the affect of very weak ducts that could bend the signals a few tenths of a degree over a distant hill.

If you lived on top of the East Bay hills Sacramento would be no problem all the time. I have a friend who lives in Walnut Creek about 1/2 way up the other side of the East Bay hills. He receives all the Walnut Grove stations with literally a dipole made out of tin foil on the back of his TV! How much of a bend do you think it would take to get those signals down to you in SF?

Chuck
post #4044 of 10449
Quote:
Originally Posted by Calaveras View Post

How much of a bend do you think it would take to get those signals down to you in SF?
Chuck

I have no idea! I know that the transmit antennas at Walnut Grove are at about 2000 feet and my home is at 325 feet and the signal has to travel over 1400 to 1650 foot peaks above Berkeley to get here. With those figures can you figure the bend?

Apparently we have been experiencing some minor ducting if the present signals are normal. During the Summer and early Fall, signals consistently were MUCH stronger than they have been lately. It would be great if we got the same ducting phenominon here that they get back east, but no such luck.

I miss it! When I lived in Chicago, I had a ball working VHF DX on 2 meters during the summer months. My record was working a guy simplex in Alexandria, Virginia, who was using an HT running 4 watts from my home in the northwest suburbs of Chicago running 25 watts to a Ringo antenna. That was amazing! Low VHF TV was a mess! I was seeing interfering signals coming in over local channels 2 and 5 and even got glimpses of pictures through the adjacent channel garbage on channels 3 and 4.

My best VHF DX from here in San Francisco was about 25 years ago working a station in New Hampshire on 6 meter simplex using just 10 watts to a vertical antenna. If I didn't live so close to Sutro I might have seen some TV DX coming in on low VHF at that time.

What's your best TV DX from up there in the hills?

Larry
SF
post #4045 of 10449
Quote:
Originally Posted by aerodynamics View Post

I have Comcast expanded basic cable and recently, maybe 3-4 days ago, I lost signal from Fox HD (Channel 2.1) and CBS HD (Channel 5.1). I'm not using a STB, it goes straight into my plasma. I've been rescanning channels everyday since with no luck. Has anyone else experienced this?

Quote:
Originally Posted by Xn0r View Post

I think Comcast is moving more and more channels to the digital cable end, so you'll need a cable box to get a lot of them now. I was recently in a comcast office, and overheard one of the employees saying that some of the old, small non digital STBs which some were still using would stop working soon.

Just rescanned channels today and both FOX and CBS HD are back. Not sure what the problem was though, unfortunately.
post #4046 of 10449
Quote:
Originally Posted by Larry Kenney View Post

I have no idea! I know that the transmit antennas at Walnut Grove are at about 2000 feet and my home is at 325 feet and the signal has to travel over 1400 to 1650 foot peaks above Berkeley to get here. With those figures can you figure the bend?

I'm going to take a guess that it's about 10 miles to the East Bay hills from SF. I checked the drop in elevation due to curvature of the Earth at 10 miles and it's only 66 feet so I'll ignore that. So using the ATN 1325/52800 is about 1.4 degrees. I don't have any feeling as to whether that's a little or a lot.

Quote:


Apparently we have been experiencing some minor ducting if the present signals are normal. During the Summer and early Fall, signals consistently were MUCH stronger than they have been lately. It would be great if we got the same ducting phenominon here that they get back east, but no such luck.

We get a lot of temperature inversions during those months so it's not surprising to see more consistent reception.

Quote:


I miss it! When I lived in Chicago, I had a ball working VHF DX on 2 meters during the summer months. My record was working a guy simplex in Alexandria, Virginia, who was using an HT running 4 watts from my home in the northwest suburbs of Chicago running 25 watts to a Ringo antenna. That was amazing! Low VHF TV was a mess! I was seeing interfering signals coming in over local channels 2 and 5 and even got glimpses of pictures through the adjacent channel garbage on channels 3 and 4.

I lived 30 miles west of Chicago for a year+ when I was 14/15. I wasn't into antennas yet but I remember we could see channel 8 from Kalamazoo and 13 from Rockford, neither very good. There were also some amazing days of UHF reception on an indoor loop. We just don't get those sort of ducts out here although I did work Hawaii from Fremont on 2M one summer during one of those ducts using a pair of KLM 22Cs and 160W.

I can imagine how sporadic-E must mess up low VHF back east. Yet another reason why it's not so good for DTV.

Quote:


My best VHF DX from here in San Francisco was about 25 years ago working a station in New Hampshire on 6 meter simplex using just 10 watts to a vertical antenna. If I didn't live so close to Sutro I might have seen some TV DX coming in on low VHF at that time.

I was able to participate in a few opening we had at the peak of the last solar cycle. I worked a few stations in east Asia on 6M with 100W and 5 element yagi. The best single day was an opening just to Japan. I came home from work to find the band open and called CQ. It lasted about 30 minutes and I had a pile-up of S9+30dB JA's. It was some of the most amazing propagation I've ever heard.

Quote:


What's your best TV DX from up there in the hills?

I don't have a low VHF TV antenna so I haven't done any that up here. On VHF I've seen KCOY analog 12 from Santa Maria which is 230 miles and 115KW and KIXE-DT 9 from Redding which is 200 miles and just 15KW. Image attached below. I see the date stamp says 9/17/08 at 12:45 pm. I think that was shortly after they transitioned. Once KVIE moves to 9 I'll never see KIXE again.

Chuck
LL
post #4047 of 10449
It was a beautiful day for a ride out of the city! We connected up the laptop to our inverter, the Fusion HDTV 7 USB analog/digital receiver to a mag-mount on the roof of the car, tuned to KMTP analog 32 and headed north across the Golden Gate Bridge on U.S. 101. Bill was driving and I was in the shotgun seat and we were off to see how the two signals on channel 32, KMTP analog from Sutro Tower and KFTY digital from Mt. Saint Helena, fought it out in their overlapping signal areas.

KMTP's signal was strong until we got on the north side of Mt. Tamalpais around San Rafael. There were lots of ghosts coming in and out of the picture all along the way, but overall, reception was quite good until then. In San Rafael the signal got pretty snowy, and by the time we got to the southern part of Novato, it was pretty much gone. I'd get occasional glimpses of it, but that's it.

During this time I would make occasional checks on KFTY digital 32 and got "No Signal", as I expected.

Through Novato I got no signal from either channel 32. I checked on KTLN 47 from Novato and was surprised to see how much the signal fluctuated. It would go from 27 dB 100% (the max signal for the receiver) to 0 dB 10 to 20% frequently while traveling within just a few miles of the transmitter. I never got a solid picture for more than 15 or 20 seconds. The hills around there really affected their 1000 kW signal causing all kinds of multipath! Highway 101 runs through the valley and over low hills, but there are hills on both sides for most of the way north. By the way, KTLN still hasn't corrected their PSIP data and they show up as 47-1, rather than 68-1 as they should.

I tuned to KRCB 23 and got a signal varying from 40 to 80% in north Novato and after going over a hill it steadily improved. I got it strong enough for the PSIP data to be detected for all three sub-channels, 22-1, 22-2 and 22-3, as we got close to Petaluma.

I went back to digital 32 and just watched the signal indicator. I got my first sign of a signal from KFTY in the southern part of Petaluma. Most of the time I got "No Signal", but every so often I'd see it register 30 or 40%, 11 or 12 dB. Finally, about the time we were in Rohnert Park the signal got strong enough to produce my first picture for KFTY and it showed up as 50-1, just like it's supposed to.

I was surprised that as we approached Santa Rosa, the city of license for KFTY, that the signal didn't improve that much. I'd get occasional hits of 27 dB 100%, but they were rare. Most of the time the signal was in the 50 to 70% range, and the picture was stopping and starting rather abruptly.

We turned onto Route 12 headed east toward Sonoma. KFTY's signal was the best about a mile east of U.S. 101, but still didn't stay in the higher ranges enough to produce a solid picture. The hills around us were chopping the signal up terribly. I switched to KRCB on Sonoma Mountain and it was solid, 85 to 100% 22 to 27 dB. We stopped at a mini-mart and I logged a file from KRCB for Trip with my TSReader program. KFTY wasn't strong enough to lock.

As we continued east on Route 12 both 23 and 32 started getting weaker and weaker as we wound through the hills. About 10 miles out of Santa Rosa I lost both signals. The hills to the north were totally blocking KFTY's signal even though we were getting closer to the transmitter site, and we were getting behind other hills that blocked KRCB.

I tuned to KMTP analog 32 and was surprised to see a fairly decent signal coming in from Sutro Tower about 55 miles to the south. Maybe that's why I was getting "No Signal" now from KFTY. ? ? ? KMTP stayed pretty solid all the way through Sonoma and into Napa, and I continued to get "No Signal" for KFTY digital 32.

In Napa we turned north on Highway 29 headed directly for Mt. St. Helena where KFTY's transmitter is located. About a mile north of downtown Napa we went around a hill and KMTP disappeared into mostly snow. I switched to KFTY and started seeing a signal again. Quickly it improved and I started getting a picture. We drove north about 15 miles out of Napa and by then KFTY's signal was holding in the 80 to 100% range with a solid picture. We turned east on a country road, pulled over in a wide spot and I logged a TSReader file for Trip for KFTY while the signal was good.

We headed east to the Silverado Trail and headed south. KFTY held up quite well out there in the valley until we got back almost into Napa. There it started to get really choppy again. I tuned to KMTP and it was starting to be seen again. Apparently the two signals are fighting it out in the Napa area. I was able to see a little of both as I switched back and forth as we drove into the city.

We stopped in Napa for dinner and I put the computer away, and I drove home after dinner, so that ends my story of the KMTP/KFTY channel 32 saga. It was a fun day, but I was surprised by the poor reception of both KTLN and KFTY. I expected better. KRCB did a decent job, more like what I thought I'd see for all three stations. I guess driving along with a vertical whip through the hills is not the way to receive a decent digital TV signal.

Larry
SF
post #4048 of 10449
Got the files and updated my site with the data included in them. Thanks!

But yeah, using an omni-directional vertical antenna on three horizontally-polarized signals isn't really the ideal method.

And as for your question, it's because the files have varying amounts of errors in them. I don't know what it is about Hauppauge cards but they just do not play nicely with TSReader. I've gotten three sets of captures from people with Hauppauge receivers, including your own, and all of them had varying levels of errors that don't actually exist (though some of them do). Each error is recorded as one of those "Unknown Usage" things at the bottom, and like to pop up when signals drop out or are weak. A capture with no errors can be as small as 10KB (varying based on subchannels, amount of EIT, etc), and in fact many of the captures I have are about that size.

- Trip
post #4049 of 10449
I live in Sunnyvale. The past days I am having trouble getting a signal from KTVU DT. (I get the analog channel ok). I was initially blaming it on the weather, but can no longer do so as the weather has improved.

Are there others in this area who are able to view KTVU programming on their box without issues ?

Also what is surprising to me is that the analog channel comes in but not the digital broadcast.
post #4050 of 10449
KTVU analog is channel 2 while digital is on channel 56 so there's a big difference. Are you getting channel 4 okay since it's digital channel is 57?

If you look at analog 44 and 66 are they strong and ghost free?

Since I'm the one who saw you post on the DTVPal DVR thread can you pass along the signal strength numbers you're seeing on some of the stations and what you had for KTVU before you lost it? That would be a good reference since I have one too.

Chuck
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