View Full Version : reception problems
bondo
18-Feb-2011, 4:49 PM
hi, I'm new to OTA. I was wondering if anyone could provide help, cause I can't seem to figure this out. My setup is a channel master 2016 antenna, 20 feet high, and 60 feet of R6 to the grounding block on the house. From there it goes another 40 feet to where it connects. When I connect it straight to a TV or digitial converter box, I don't have any issues with freezing or pixelation. My goal is to hook it up to my HDHOMERUN dual tuner. In order to do that I split the incoming cable, and then run it to the 2 inputs of the tuner. It degrades the signal to where channel 13 FOX(vhf) constantly freezes, and channel 7 freezes sometimes. I tried putting a motorola signal booster in place of the splitter, and also at the point where the cable enters the house. Same results. I've tried pointing the antenna in different directions with no luck. Again, I seem to get a good picture with nothing inbetween the cable and TV. I would think a simple signal booster would help make up for the minor splits but it doesn't. My tvfool report is below, any ideas? thanks.
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3db9c976cf5d4ecc
John Candle
18-Feb-2011, 5:22 PM
I suggest a CM7778 preamp installed close to the antenna. The stations to the east/north east are weak and FOX 13 is being received on the back side of the antenna reducing the signal. The splitter reduces the signal to the point that digital lock is lost. The preamp needs to be installed close to the antenna , like directly below the antenna. . As always , look in the connectors on the ends of the coax , if outer shied and shield wires of coax are pushed in toward the center wire then push away from center wire. Look and see if foam is on the center wire , if so then scrape it off , foam is a insulator. . Read and understand this about , Real Digital Tv Channels , Virtual Digital Tv Channels , Analog Tv Channels , , http://forum.tvfool.com/showthread.php?t=695
Tower Guy
18-Feb-2011, 6:07 PM
It degrades the signal to where channel 13 FOX(vhf) constantly freezes, and channel 7 freezes sometimes. I tried putting a motorola signal booster in place of the splitter, and also at the point where the cable enters the house. Same results.
Your strongest signal freezes and you're thinking amplification.....I'm thinking antenna aiming.
There's no way that a single antenna will be optimum for all of your stations unless you want a rotor.
I have two suggestions:
The Winegard HD-1080 has a VHF pattern that is opposite the UHF pattern. That should solve the FOX problem, but cause a problem with KTBW. (you may not care)
You could install two antennas and connect them to the two inputs of the dual tuner version of the HD HomeRun.
Both antennas should be rated for channels 7-69. The one aimed at 66° should be larger than the other.
An optimum antenna for 66° could be a HD 7496P with an AP 8700 preamp. More gain would loose some signals off the side, less gain would make CBS unreliable.
bondo
18-Feb-2011, 6:59 PM
thanks for the suggestions. Tower Guy, I don't really understand why I can't pick up Fox 13 really well. For the sake of that one channel, I've rotated my antenna 360 degrees in increments and really saw no noticable change in signal quality. I've also tried rabbit ears around the house for testing and couldn't really pick it up. Very strange, as the Fox 13 tower is only 2-3 miles away from me towards the west. I'm sure there's hills and trees blocking line of sight, but being that close I would think it wouldn't matter, especially for vhf. I think I'll give that winegard hd-1080 a try, along with a preamp. thanks
Tower Guy
18-Feb-2011, 7:48 PM
I've rotated my antenna 360 degrees in increments and really saw no noticable change in signal quality.
The 2016 has almost no directivity on VHF. Multipath may be the culprit. The HD-1080 would help that, but if you're very close to hills, you might want more gain to further eliminate ghosting.
bondo
18-Feb-2011, 8:13 PM
The 2016 has almost no directivity on VHF. Multipath may be the culprit. The HD-1080 would help that, but if you're very close to hills, you might want more gain to further eliminate ghosting.
yeah where I'm located, right next to a huge vertical wall about 200 feet high directly west, and high hills basically west to northwest, I'm not sure I can do much better with any antenna. In my tests I was able to receive 13 well enough with a straight line and no splitting, so if I can just keep it strong all the way through splitting I think it'll be fine. I ordered the preamp from amazon 1 day shipping so I'll try that tomorrow and go from there.
bondo
19-Feb-2011, 5:06 PM
UPDATE: I received the CM7778 and installed it. My reception didn't do any better, in fact it seemed a little worse. I think I pretty much give up on getting a good signal here, with the billions of tall trees and hills.
John Candle
20-Feb-2011, 2:39 AM
"yeah where I'm located, right next to a huge vertical wall about 200 feet high directly west"
Dave Loudin
20-Feb-2011, 12:33 PM
UPDATE: I received the CM7778 and installed it. My reception didn't do any better, in fact it seemed a little worse. I think I pretty much give up on getting a good signal here, with the billions of tall trees and hills.
Tower Guy provided some recommendations, and if I recall correctly, told you that a preamp would not help. Before you give up, why don't you try want he recommended?
bondo
23-Feb-2011, 11:28 AM
Tower Guy provided some recommendations, and if I recall correctly, told you that a preamp would not help. Before you give up, why don't you try want he recommended?
I had looked up the antenna he suggested, the Winegard 7496P but couldn't find any information on it at all. And he did suggest a preamp with it.
Tower Guy
23-Feb-2011, 1:58 PM
I had looked up the antenna he suggested, the Winegard 7496P but couldn't find any information on it at all. And he did suggest a preamp with it.
My dislexia is the problem.
http://www.solidsignal.com/pview.asp?mc=03&p=HD7696P&d=Winegard-HD7696P-High-Definition-VHFUHF-HD7696-Series-TV-Antenna-%28HD7696P%29&c=TV%20Antennas&sku=
bondo
24-Feb-2011, 2:58 PM
My dislexia is the problem.
http://www.solidsignal.com/pview.asp?mc=03&p=HD7696P&d=Winegard-HD7696P-High-Definition-VHFUHF-HD7696-Series-TV-Antenna-%28HD7696P%29&c=TV%20Antennas&sku=
ahh, thanks, I'll give that one a shot. Also, the readings on my hdhomerun say that 13 has a signal strength of 90/100, and the signal quality is much lower and fluctuates. Would that be a possible symptom of that multipath you spoke of?
Tower Guy
24-Feb-2011, 4:52 PM
The readings on my hdhomerun say that 13 has a signal strength of 90/100, and the signal quality is much lower and fluctuates. Would that be a possible symptom of that multipath you spoke of?
Yes, strong signal and low quality are the exact symptoms of multipath.
bondo
24-Feb-2011, 5:20 PM
Yes, strong signal and low quality are the exact symptoms of multipath.
If I go the 2 antenna route, and go with a decent VHF directional antenna, what would you suggest I use to combine the UHF pointing at around 66 and the VHF into one cable?
Tower Guy
24-Feb-2011, 6:34 PM
If I go the 2 antenna route, and go with a decent VHF directional antenna, what would you suggest I use to combine the UHF pointing at around 66 and the VHF into one cable?
It's not that simple. You have VHF stations arriving from 279° and 73°. Your UHF stations arrive from 66° to 94°.
Therefore you need two VHF antennas and a broad beam UHF antenna with good F/B ratio or a 7-69 antenna aimed at 82° plus a VHF only aimed at 279°. I can't predict which antenna combination would work best with your terrain. I can predict that trying to combine them into a single feed will be hard and/or expensive. That's why the suggestion to use the dual inputs of your HD Homerun, one for each of two antennas aimed in different directions.
bondo
24-Feb-2011, 7:05 PM
It's not that simple. You have VHF stations arriving from 279° and 73°. Your UHF stations arrive from 66° to 94°.
Therefore you need two VHF antennas and a broad beam UHF antenna with good F/B ratio or a 7-69 antenna aimed at 82° plus a VHF only aimed at 279°. I can't predict which antenna combination would work best with your terrain. I can predict that trying to combine them into a single feed will be hard and/or expensive. That's why the suggestion to use the dual inputs of your HD Homerun, one for each of two antennas aimed in different directions.
again, thanks for all the suggestions. The VHF channel at 73(channel 11 vhf) isn't important to me, so I can just focus on the 279 and one vhf antenna. As for the uhf, abc/nbc/cbs are pretty much at 66/67. So I'll do like you said and get a stronger uhf, but point it around 66/67? I really don't care about the other channels. And channel 11, the other vhf channel, comes in pretty easy no matter what I do. Before I run another cable, I think I'll just hook up the vhf antenna by itself and point it at 279 to make sure it will work before I run an extra cable. Any suggestions on a vhf only antenna? I saw this one at RS for $26 shipped, seems to have good reviews and is only a vhf antenna. Antennacraft Y5713 also, would it be a possibility to use a channel 13 join-tenna to combine both antennas?
GroundUrMast
24-Feb-2011, 8:45 PM
Judging from the path profiles in your original TVF report (click on the station call sign), going up will buy you far more than any amplifier or antenna upgrade. (That's not to say you won't benefit from an antenna upgrade.)
Given the proximity to KTBW and KCPQ, amplification will likely be overloaded if you get the additional signal I expect.
Experiment with the Interactive TV Map (http://www.tvfool.com/?option=com_wrapper&Itemid=90) using different placements of the antenna and mounting height. I think you will see signal levels change significantly with relatively small changes. If I'm wrong, only a few minutes of time spent.
As T.G. mentioned earlier, depending on the HTPC software package you use, you can dedicate individual ports on the HD HomeRun to separate antennas. Thread 820 (http://forum.tvfool.com/showthread.php?t=820) That has allowed me to avoid the need for Jointennas.
bondo
24-Feb-2011, 9:16 PM
Judging from the path profiles in your original TVF report (click on the station call sign), going up will buy you far more than any amplifier or antenna upgrade. (That's not to say you won't benefit from an antenna upgrade.)
Given the proximity to KTBW and KCPQ, amplification will likely be overloaded if you get the additional signal I expect.
Experiment with the Interactive TV Map (http://www.tvfool.com/?option=com_wrapper&Itemid=90) using different placements of the antenna and mounting height. I think you will see signal levels change significantly with relatively small changes. If I'm wrong, only a few minutes of time spent.
As T.G. mentioned earlier, depending on the HTPC software package you use, you can dedicate individual ports on the HD HomeRun to separate antennas. Thread 820 (http://forum.tvfool.com/showthread.php?t=820) That has allowed me to avoid the need for Jointennas.
you're from seattle area? so you have to deal with that pesky 13 also eh. ;) I just checked the map adjusting the height, and channel 13 stayed the same, pretty strong. Right now that's my main concern. It's really close by and the signal strength is very strong but quality is really bad. I'm not too concerned about the eastern channels I think with a good directional UHF I can lock into those in the seattle area pretty well, as I'm getting them pretty good right now. So for 13 I'm thinking tower guy must be right about multipath, and maybe a good directional VHF would help with that. Here's a picture of my topopgraphy, maybe it will help. As you can see the one to the west(13) is being blocked by some huge hills. But actually my house is closer to that first hill on the left.
http://owisoft.net/Documents/map.JPG
GroundUrMast
24-Feb-2011, 10:31 PM
I agree with T.G., this is certainly a fight with multipath. If you can not mount any higher, for whatever reason then there is no point researching it... As I looked at it, it appeared that you would get substantially better signal from the stations on Queen Anne, Capitol Hill and West Tiger if you could get above 35' AGL.
I would expect the multipath problems for KCPQ would be less also. That would also make me try a single antenna solution, with KCPQ on the back side of the antenna.
So, if you are limited to the existing mounting AGL, two antennas make sense. You don't need the gain, but the directivity of an Antennacraft Y10713 (http://www.antennacraft.net/pdfs/Y10-7-13.pdf)makes it my choice for a dedicated CH-13 antenna at your location. (Directivity is a primary antenna quality useful for combating multipath.)
For the Seattle stations, I agree with the Winegard 7496P already suggested.
bondo
24-Feb-2011, 10:42 PM
I agree with T.G., this is certainly a fight with multipath. If you can not mount any higher, for whatever reason then there is no point researching it... As I looked at it, it appeared that you would get substantially better signal from the stations on Queen Anne, Capitol Hill and West Tiger if you could get above 35' AGL.
I would expect the multipath problems for KCPQ would be less also.
You don't need the gain, but the directivity of an Antennacraft Y10713 (http://www.antennacraft.net/pdfs/Y10-7-13.pdf)makes it my choice for a dedicated CH-13 antenna at your location. (Directivity is a primary antenna quality useful for combating multipath.)
ok thanks. Yeah 35' is probably not doable for me, not with my setup anyways. I'm just using EMC conduit that that I made slide into fence stock a couple feet, and attached to a deck. Feels sturdy at 20' but 35 would be pushing it. I could definitely see the benefit for doing 35 especially for cbs.
Tower Guy
25-Feb-2011, 3:19 PM
would it be a possibility to use a channel 13 join-tenna to combine both antennas?
Perhaps the Jointenna would work. If not try a UVSJ.
The Jointenna would allow for reception of PBS when using a 7-69 antenna aimed at 82°. The UVSJ would filter out PBS on channel 9 and a UHF only for 82° would be OK.
If a Jointenna works, that's an ideal solution; but a Jointenna could allow some channel 13 from the 7-69 antenna to creep in, making the multipath worse instead of better.
bondo
25-Feb-2011, 7:21 PM
Perhaps the Jointenna would work. If not try a UVSJ.
The Jointenna would allow for reception of PBS when using a 7-69 antenna aimed at 82°. The UVSJ would filter out PBS on channel 9 and a UHF only for 82° would be OK.
If a Jointenna works, that's an ideal solution; but a Jointenna could allow some channel 13 from the 7-69 antenna to creep in, making the multipath worse instead of better.
ok thanks, I'll give it a shot. If a vhf only antenna works for 13, I'll try a uhf only antenna along with a jointenna for the other direction. Also, PBS isn't a channel I watch or want. So would I still want to point the uhf that far south at 85 degrees, or pretty much directly at abc, nbc, and cbs which are pretty much lined up at around 66 degrees?
Tower Guy
25-Feb-2011, 9:19 PM
So would I still want to point the uhf that far south at 85 degrees, or pretty much directly at abc, nbc, and cbs which are pretty much lined up at around 66 degrees?
66. There are some indies and ION that might not work at 66, but CBS should be much better.
GroundUrMast
25-Feb-2011, 11:06 PM
If I'm reading right, you don't care about any VHF other than KCPQ-13 and the only UHF priorities are KOMO-38, KING-48 and KIRO-39 (or the translator on 51).
So ditch the combo antenna aimed at Seattle, go with the big guns, an Antennas Direct XG-91 aimed at 66° (true) and an Antennacraft Y10713 aimed at 279° (true). Join them with a UVSJ.
That gives you the best shot at reliable KIRO KCPQ signals which might successfully split up to four ways with no amplifier (but you already own one or more if it's needed).
The Winegard 7496P is a fine antenna but has high-VHF capability you say you don't need. The increased gain and directivity of the XG-91 going to be of more value to you than reception of VHF 9 and 11.
bondo
25-Feb-2011, 11:53 PM
great, thanks for the great advice guys, I'll let you know how it turns out.
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