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Ok...I had some time today and re-installed my antenna in the new, permanent location again. At first it was the same result, so I went back with the RCA preamp (TVPRAMP1Z) that I was using at the old location instead of the Kitztech and low and behold I started seeing some VHF...only KVIE though, no KXTV.

With this info I went ahead and installed a slightly taller mast...roughly 4-5-feet taller and there it was, all the channels including KXTV without any dropout (so far).

Still hard to believe how hit or miss the signal is on my roof...and the RCA preamp ended up working better than the Kitztech in my situation.

Whatever works for you. There's no reason I can see why the RCA should outperform the Kitztech. I measured each on the bench and the RCA is not better in any way that counts. 3rd order intermods are about the same on VHF but far worse on UHF. The Kitztech noise figure is far better, especially on VHF. The Kitztech gain is higher on VHF than the RCA but lower on UHF.

Chuck
 

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I hope KXTV stays okay. Antenna location outdoors is subject to the same factors that influence the location for antennas indoors, like multipath. You're in the El Dorado County hills there. That means there's lots of grass-covered rocks with true-line-of-sight to Walnut Grove. Reflected signals certainly matter.
Yeah I spoke too soon I guess, as KXTV is now gone this morning and KVIE is very weak.

Very disappointing...I don't think I can get any more height out of my setup as I am limited to an eave mount since my roof is concrete tile
 

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Yeah I spoke too soon I guess, as KXTV is now gone this morning and KVIE is very weak.

Very disappointing...I don't think I can get any more height out of my setup as I am limited to an eave mount since my roof is concrete tile

This sounds more and more like it's a multipath problem due to the antenna position sensitivity. It's pretty unlikely that the signals are just too weak to receive. One of my complaints about commercial antennas is that they're all designed for maximum gain. Maximum gain and maximum rejection of side and rear signals are mutually exclusive. Most people with reception problems don't need maximum gain. They need a clean pattern. Unfortunately there's more than one kind of multipath. There is multipath from reflections from nearby mountains and buildings and there is multipath that occurs on the main path due to vegetation and diffracted rays crossing each other. The former can be improved with a good antenna pattern. No antenna can fix the latter. You just have to find a better location. That location may be impossibly high.

If you want to build a high VHF antenna optimized for low side and rear lobes I can supply the plans for the antenna in the attached image. If this antenna doesn't work, then the problem is probably unsolvable in any realistic way.

Chuck
 

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This sounds more and more like it's a multipath problem due to the antenna position sensitivity. It's pretty unlikely that the signals are just too weak to receive. One of my complaints about commercial antennas is that they're all designed for maximum gain. Maximum gain and maximum rejection of side and rear signals are mutually exclusive. Most people with reception problems don't need maximum gain. They need a clean pattern. Unfortunately there's more than one kind of multipath. There is multipath from reflections from nearby mountains and buildings and there is multipath that occurs on the main path due to vegetation and diffracted rays crossing each other. The former can be improved with a good antenna pattern. No antenna can fix the latter. You just have to find a better location. That location may be impossibly high.

If you want to build a high VHF antenna optimized for low side and rear lobes I can supply the plans for the antenna in the attached image. If this antenna doesn't work, then the problem is probably unsolvable in any realistic way.

Chuck

A quick update...Around 6pm or so, I was going through the channels and there was KXTV. It had a solid signal...over 50 on the TV "signal strength" meter.

This was about the same time as yesterday when I was receiving KXTV and KVIE.

Any thoughts...?
 

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Yeah I spoke too soon I guess, as KXTV is now gone this morning and KVIE is very weak.

Very disappointing...I don't think I can get any more height out of my setup as I am limited to an eave mount since my roof is concrete tile
If true line-of-sight isn't available, you are forced to look for a sweet spot for reception that can handle the multipath. It's all about location. Before you give up, you can try seeing if a lower antenna height might work. You've got the items necessary already. See what happens below the leaves of the trees. Alternate antenna aims might also work. Got a significant line-of-sight hill nearby with a bank shot to the south? Try anything. It's about fully employing your current antenna before giving up on it. Good Luck.
 

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A quick update...Around 6pm or so, I was going through the channels and there was KXTV. It had a solid signal...over 50 on the TV "signal strength" meter.

This was about the same time as yesterday when I was receiving KXTV and KVIE.

Any thoughts...?

It's common to see variations in signal strength over 24 hours when you don't have line-of-sight. Most typically temperature inversions form late in the day and last until the following morning. Signals are slightly bent down and increase the signal strength and extend the range of the station. Afternoons are often the worst reception as inversions are broken up due to solar heating. Your situation may not conform exactly to this but it's likely what is going on. Temperature inversions don't form when it's raining so people often complain that signals are worse in the rain, incorrectly thinking the rain attenuates the signals when it's just a lack of temperature inversions.

Chuck
 

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It's common to see variations in signal strength over 24 hours when you don't have line-of-sight. Most typically temperature inversions form late in the day and last until the following morning. Signals are slightly bent down and increase the signal strength and extend the range of the station. Afternoons are often the worst reception as inversions are broken up due to solar heating. Your situation may not conform exactly to this but it's likely what is going on. Temperature inversions don't form when it's raining so people often complain that signals are worse in the rain, incorrectly thinking the rain attenuates the signals when it's just a lack of temperature inversions.

Chuck

Same thing tonight...I got home a bit early and tried KXTV around 4pm and the signal was not there; however by 6pm I had a decent signal.

Is VHF more likely to be affected by inversions...really did not see much fluctuation with the other channels (besides KVIE).
 

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Thanks for the update! This should now allow KFMS to move from 47 to 31. I'd appreciate hearing when that happens and also when KMMW moves from 28 to 14. Those are the only Sacramento-Stockton area stations that I show that haven't moved.

I appreciate your input so that I can keep my station lists up to date.

Larry

Hello. I'm new to the forum but have been monitoring for awhile and enjoying the discussion. As a KTVU fan, I was sure hoping that KFMS wasn't going to move to 31. As of the last week or so, they are dark on 47 which probably makes sense if they are getting ready to move. And with KMUM moved, I have KTVU back for the time being.



My location is in El Dorado Hills at 1250 feet with a clear southwest line of sight across the valley towards Mt. Diablo. Luck has it that the path from my rooftop to Mt. Sutro is within 2 degrees of Walnut Grove. With a Hauppauge WinTV-dualHD, I receive Sacramento channels at SNRs of 29 to 31 and Sutro UHF channels in the 25 to 28 range. Sutro VHF-Hi a bit lower with KRON very intermittent. Something must be going on with KQED/KQEH as they disappeared where I used to receive them with signals in the 25 range.



My biggest surprise is being able to receive KAXT (1.2) in the 16 - 20 range. Usable, but far from perfect. But not bad for 100 miles away and only 15kw. The antenna here is a roof-mounted RCA ANT705E that I've been generally happy with but I have a new Televes Ellipse Mix on its way. Time to play!:D


Cheers!
Craig
 

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Hello. I'm new to the forum but have been monitoring for awhile and enjoying the discussion. As a KTVU fan, I was sure hoping that KFMS wasn't going to move to 31. As of the last week or so, they are dark on 47 which probably makes sense if they are getting ready to move. And with KMUM moved, I have KTVU back for the time being.



My location is in El Dorado Hills at 1250 feet with a clear southwest line of sight across the valley towards Mt. Diablo. Luck has it that the path from my rooftop to Mt. Sutro is within 2 degrees of Walnut Grove. With a Hauppauge WinTV-dualHD, I receive Sacramento channels at SNRs of 29 to 31 and Sutro UHF channels in the 25 to 28 range. Sutro VHF-Hi a bit lower with KRON very intermittent. Something must be going on with KQED/KQEH as they disappeared where I used to receive them with signals in the 25 range.



My biggest surprise is being able to receive KAXT (1.2) in the 16 - 20 range. Usable, but far from perfect. But not bad for 100 miles away and only 15kw. The antenna here is a roof-mounted RCA ANT705E that I've been generally happy with but I have a new Televes Ellipse Mix on its way. Time to play!:D


Cheers!
Craig
Welcome to the Forum!

You've got a good location if you're able to receive the UHF stations from Sutro Tower so well. It's too bad that local stations are blocking KTVU for you.

I have the same problem for a couple of Sacramento stations with local stations on channels 22 and 24, blocking KTXL and KMAX. There's also a station on 23 but it's shooting its signal toward San Jose and not blocking KQCA.

Good luck with you new antenna. Hopefully it'll pull in a few more stations for you, including better signals on VHF. I've been told that KDTV 14 and KTSF 26 on channel 20 from the hills above Fremont have a good signal into the Central Valley, so you might want to check them out. Since you get low power KAXT 1 / KTLN 68, hopefully on their new channel 22, not 42, you should get 20. 42 is bring turned off today.

KQED/KQEH is temporarily operating on lower power than normal, so that's probably why you're not receiving it now. They didn't say why or for how long they'll be on the lower power.

Larry, WB9LOZ
 

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Kxtv-ld

What is KXTV-LD?
I noticed the tuner has 2 versions of channel 10.1 and the version labeled KXTV-LD has the worst reception.
I think the tuner sometimes locking onto that version is exacerbating the reception issues with KXTV.
 

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What is KXTV-LD?
I noticed the tuner has 2 versions of channel 10.1 and the version labeled KXTV-LD has the worst reception.
I think the tuner sometimes locking onto that version is exacerbating the reception issues with KXTV.
That is a low-power translator that KXTV operates on RF 36. The transmitter is located at their studio site (400 Broadway). TiVo sees this is addition to the RF 10 transmission, but it allows for the RF 36 version to be de-selected and thus ignored. Guessing your tuner doesn't offer that option?
 

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Welcome to the Forum!

You've got a good location if you're able to receive the UHF stations from Sutro Tower so well. It's too bad that local stations are blocking KTVU for you.

I have the same problem for a couple of Sacramento stations with local stations on channels 22 and 24, blocking KTXL and KMAX. There's also a station on 23 but it's shooting its signal toward San Jose and not blocking KQCA.

Good luck with you new antenna. Hopefully it'll pull in a few more stations for you, including better signals on VHF. I've been told that KDTV 14 and KTSF 26 on channel 20 from the hills above Fremont have a good signal into the Central Valley, so you might want to check them out. Since you get low power KAXT 1 / KTLN 68, hopefully on their new channel 22, not 42, you should get 20. 42 is bring turned off today.

KQED/KQEH is temporarily operating on lower power than normal, so that's probably why you're not receiving it now. They didn't say why or for how long they'll be on the lower power.

Larry, WB9LOZ
Thanks Larry, I do receive KDTV/KTSF at 28 SNR. I also see that KAXT/KTLN moved today to RF22. No joy now since KTXL in Walnut Grove @ 30 SNR blocks them entirely. I just did a quick signal scan before I head up on the roof to swap antennas and I'll report the results.


Regarding KTVU/KFMS, I no longer receive KTVU on 31 and I assumed it was being blocked by KFMS. But after a rescan of 31 nothing showed up? Neither KTVU nor KFMS. A quick check with my RTL-SDR shows an active ATSC pilot on 572.31Mhz but I can't tell whose it is. Unlike all the other ATSC pilots I see, this one has a beat to it which leads me to believe that it may be both KTVU and KFMS at similar received signal levels. I'm hoping that the antenna change will yield better results for KTVU.


Craig
WB6LZV
 

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Regarding KTVU/KFMS, I no longer receive KTVU on 31 and I assumed it was being blocked by KFMS. But after a rescan of 31 nothing showed up? Neither KTVU nor KFMS. A quick check with my RTL-SDR shows an active ATSC pilot on 572.31Mhz but I can't tell whose it is.
Welcome to the forum! As far as I know, KFMS has not yet powered up on RF 31. I heard there was some kind of an issue that they are working to resolve, and that it may come up soon. I'm going to be out that way tomorrow and may take my AirSpy device along to check on it. I'll post what I find.

Edit: Confirmed that KFMS *is* on-the-air, on RF 31.
 

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Thanks videojanitor! I did an antenna swap yesterday with generally good results. The swap was an RCA705E with a Televes Ellipse Mix. The Televes seems to be a very well-made antenna by the way. Pics attached. With the antenna pointed directly at Mt. Sutro, didn't have any noticeable effect on the Walnut Grove channels, but it did improve some of the Sutro channels by 2 - 3 db SNR. No surprise there.


A pleasant surprise was that the Televes exhibited just enough side rejection to help null out KXTV's low power signal on RF36 to allow very strong reception of KICU 36 on Mt. Allison. Upon pointing the Televes at Mt. Allison, I also am able to receive KNTV/KSTS on RF19 quite well. The ~25 degree directional shift from Sutro to Allison did reduce the Sutro and San Bruno signals by as much as 4 - 5 db SNR, but still very usable most of the time. Still not receiving KTVU RF31, however. If you find that KFMS isn't on air on RF31, then I may have some local interference as KTVU RF31 normally bangs in here. I have an HDHomeRun Quattro on it's way and I'll compare with the WinTV-dualHD that I'm running now.


Cheers,
Craig - WB6LZV
 

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Congratulations, Craig, on the new Televes antenna. Sounds like it's working well for you for both the Sutro and the Mt. Allison stations, in addition to Walnut Grove. It's an interesting looking design. I haven't seen anything like it.

Larry
 

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Now that all channel moves have been made and the Walnut Grove stations are running full power, I've been able to do a post re-pack review of my reception of the Walnut Grove stations. I'm happy with the results; I'm better off now than I was prior to the re-pack.

I can receive the following stations most of the time strong enough to get solid pictures. Signal strength varies a lot during different times of the day and night, so I occasionally lose a station or two, but I can watch programming most of the time on:
RF 9 virtual 6 KVIE
RF 10 virtual 10 KXTV
RF 23 virtual 58 KQCA
RF 24 virtual 31 KMAX
RF 25 virtual 13 KOVR

KTXL 22/40 is blocked by KAXT/KTLN on 22 and both KSPX on 21 and KTFK on 26 don't send strong enough signals in this direction. KCRA on 35 is on the same channel as KGO's translator and I get neither channel as a result.

Larry
 

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My biggest surprise is being able to receive KAXT (1.2) in the 16 - 20 range. Usable, but far from perfect. But not bad for 100 miles away and only 15kw.

KAXT uses a highly directional antenna and has very little power headed north or east. If you look up KAXT on Rabbitears and view the antenna pattern it shows just 5-10 watts in your direction. I'm not sure I believe that but be assured it's no where near 15 KW in your direction!

Chuck
 

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KAXT uses a highly directional antenna and has very little power headed north or east. If you look up KAXT on Rabbitears and view the antenna pattern it shows just 5-10 watts in your direction. I'm not sure I believe that but be assured it's no where near 15 KW in your direction!

Chuck

Thanks, Chuck. I don't put tremendous faith in the radiation plots either. But it was fun for that brief time being able to receive that weak of a signal this far away before the change to 22.



I was intrigued by your username "Calaveras". Looks like you may have lived in the county awhile back? I grew up in West Point and graduated from Calaveras High in the '70s. As a kid I used to climb pine trees and install TV antennas as a side job. Lots of fond TVDX memories from those days.


Craig - WB6LZV
 
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