Picking up local HDTV in Santa Clarita valley.

GSMnow

I have been trying to get the best signal possible for 3 years now. Antenna Web shows my address with no digital channels available. I am only 30 miles from the transmitters at Mount Wilson, but I have a mountain range between us.

My current setup is a CM4228 8 bay UHF antenna, on a 12 foot mast, with a rotor, and a Spartan pre-amp. This is feeding to any one of 3 different tuners. If I split it, I get nothing. I have a MyHD MDP-120 pvr card in my computer, I have a Dish Network 811 which has an ATSC tuner, and I just picked up a Pinnacle ultimate HD USB stick.

The MyHD MDP-120 is only a 4th gen tuner, but it actually seems to be the best out of the 3. With the amp in line, I can get CBS and NBC all the time, with no issues. If the weather is just right, I have been able to get KCET and KTLA as well. I also lock in 2 of the spanish language digital channels. On a very rare occasion, I have gotten KTTV (Fox) to show up, but not for long.

With the Dish 811, reception is about the same, maybe a little worse. I assume it is also a gen 4 tuner.

The new USB stick should be a gen 5 tuner, so I expected to pull in a few more channels, but I was wrong. With the amp in line, it will only get CBS and NBC, nothing else will lock. On KCET, it sows over 60% on signallevel, but 0% on signal quality. I took the amp out of the path and the signal level dropped to ony 35%, but the quality came up to 70%, but still no lock.

I think I do need an amp, but the Spartan's 23 db is just too much and I am over loading it. Some of the channels are not as blocked as others, which is why I have an overloaded amp along with weak signal.

What I think I need to try is a very good broad band amp that is only 8 to 10 DB with high headroom. Does anyone know of something like this? Hopefully without a crazy price tag. Any suggestions of a really cleam

I would also like to get my antenna a little higher, but it is already the tallest thing in my sub division. It is about 12 feet above my lower roof, still 7 feet above the upper roof.

I do not know my actual altitude, and since I cannot see the towers, I can tell if I am aiming right at them, or too low. Will up tilt help? Should I shoot for the ridge of the mountain I am skirting over?

How can I find out if my new USB stick is the new generation with the gen 5 tuner chip set? I got more HD channels with a stick antenna out in Beach Cities which is further from the antennas.

Signal quality appears to be a bigger issue than strength.

I hope to mess with the aiming a little more, but the strength meter only shows valid during the channel selecting mode. I also have a rotor to help aim it in, but without signal meter, it is pretty useless as an aimer.

I saw trhat in Feb 09 several of my HDTV channels will be going to the VHF high band are. How well does the CM4228 work at high band VHF? I actually get a snowey, but sorta watchable pickture on a few of the analog UHF channels.

Thanks for any advice.
Gary

otaota

Wow, those mountains can sure be a pain in the **s. It looks like the mountain casts a signal shadow across the entire Santa Clarita valley. See the attached KNBC-DT coverage map as an example. The color codes on the map, according the site where these came from (www.tvfool.com) are as follows.



In very rough terms, the colors can be broken down as follows (not related to Antennaweb):

- White is extremely strong. Beware of signal overload on amps.
- Red-yellow-green are all quite strong. You can expect reasonable coverage with an indoor antenna.
- Cyan is where it's advisable to move the antenna up to the second floor or attic.
- Blue is where it's probably necessary to install a good antenna on the roof.
- Purple is quite weak and you really have to work at it for any chance of reception.



Depending on your exact location, it looks like the signal strengths are anywhere from very weak to non-existent. The situation you're describing definitely sounds like you're in the purple category. Most the other Mt. Wilson transmitters have coverage similar or worse than this. The signals actually get stronger as you move away from Mt. Wilson because those areas are not as deep in the shadowed zone.

The reason KCBS, KNBC, KCET, and KTLA are your best channels is because of the their transmitter locations. KCBS is currently the tallest of the transmitters, followed by KNBC, and the rest are grouped a bit lower than that. The second attachment shows a Google Earth representation of the transmitters on Mt. Wilson looking down over the Los Angeles basin. Santa Clarita is off to the right of this image and you can see how KCBS has the best vantage point for reaching into your area.

BTW, after the analog shutdown, KCBS is reportedly moving to a lower transmitter location. When that happens, KNBC will be king of the hill.

A good overload-tolerant amp is the Winegard HDP-269. However, I find it hard to believe that you are having signal overload problems. What strong signals could possibly be causing overload issues? The entire area seems to be in a pocket shielded from signals on all sides.

FYI, a 4-way splitter will cause about 7-8 dB of signal loss. Some 3-way splitters are actually 4-way splitters internally, so they might not do any better than this. If you also consider the length of your coax runs (~7 dB?) and the noise figure of your receivers (~6-9 dB?), then your 23 dB amp isn't really all that much.

Tilt the antenna up slightly above the ridge line. The surface-wave and diffracted energy will be the highest at that point. Transmitted energy will not pass directly through the mountain, but it can bend over the top. When the weather conditions are right, you'll also get some signal off the sky.

VHF channels bend over mountains better than UHF channels, so in shadowed situations such as yours, there would actually be more signal power reaching you (in the air). However, the CM 4228 antenna's VHF performance is far lower than its UHF performance. Using a UHF-only antenna for picking up VHF channels this way is fine if the signals are pretty strong, but in your case it's not good enough. The net effect is that the signal you pull out of the air would probably be weaker than what you see now.

Your best bet would be to add a VHF-only antenna to your existing CM 4228 and join them with a UHF/VHF diplexer. The CM 7777 acts as a pre-amp and diplexer all-in-one, but since you already have an amp, you can get something like a UVSJ combiner and use your existing amp.

Cheers,

Attached Images

	KNBC-Santa-Clarita.jpg (137.8 KB, 25 views)
	Mt-Wilson-digital.jpg (155.3 KB, 18 views)

__________________
Chuck

GSMnow

Thank you for the very detailed information.
Chuck wrote:
<<Wow, those mountains can sure be a pain in the **s. It looks like the mountain casts a signal shadow across the entire Santa Clarita valley. See the attached KNBC-DT coverage map as an example. The color codes on the map, according the site where these came from are as follows.



In very rough terms, the colors can be broken down as follows (not related to Antennaweb):

- White is extremely strong. Beware of signal overload on amps.
- Red-yellow-green are all quite strong. You can expect reasonable coverage with an indoor antenna.
- Cyan is where it's advisable to move the antenna up to the second floor or attic.
- Blue is where it's probably necessary to install a good antenna on the roof.
- Purple is quite weak and you really have to work at it for any chance of reception.>>

My house is actually just north of newhall ranch road, a little east of the end of the greenish area. I think one or two transmitters are just able to hit my antenna causing the amp overload issue. The reason
I suspect overload is the fact that the signal quality on the USB tuner droped greatly with the amp in place. From the ground, my antenna is probably close to 30 feet up. I am not able to get up there myself to see what the antenna sees. I have to assemble the mess flat on my lower roof and pus it up vertical, and bolt it to the side of the upper roof. The rotor sits about 2 feet above the upper roof and then there is 5 feet more mast to the 8 bay antenna.

I did a little trig with the elevations and a direct line to the top of Mt. Wilson appears to be at about a 2 degree incline from my location. I can't find data on how high the mountain range is between us though. With the difficulty in tilting my antenna, what is a "best guess" for an up tilt to try? Should I just start a 2 degrees up, or go a bit more for the arc over the mountain range? 2 degrees is about 1 inch out at the bottom of the antenna. When I do get KCET, a bird landing on my antenna causes it to freeze.

I have a pretty good condition U/V 70 mile rated antenna, it is a HUGE heavy beast. The UHF yagi section is almost 4 feet long by itself. I was not able to get it more than 3 feet over my high roof without bending my mast in even a light breeze, let alone the winds we can get here. I amy have to look into a moderate sized VHF only I can get up higher. And I will have to go to a heavier gauge mast. My friend used water pipe, but it was so heavy on it's own, it seemed to sway worse. The 4228 has held up to huge winds with just a little sway. I was concerned it was gong to snap, only to see it move just a few inches. The thin elements and mesh reflector is a very good design.

I had very mixed feelings when I saw the final channel post. I was hoping they would all end up low in UHF, but at least all the VHF will be high band VHF so all is not totally lost. In theory, the elements can be a little shorter for optimum high band reception. And with the better curving of the signal, I just might get something.

I will look into the Winegard HDP-269 amp. I want to avoid going back to a mast mount amp as it is impossible to get to without a big ordeal. Looking at the specs, it does seem like a better fit. Since it is Coax in and out, I can put it at the base of my mast instead of at the antenna where the Spartan3 was. I replaced the Spartan with a Balun for now.

My total cable run from antenna to tuner is only 20 to 25 feet. My PC DVR is on a closet on the other side of the wall of the mast on the second floor, so cable loss is not a real issue. At most I would split it 2 ways. I want the PC DVR, either the MyHD 120 or the USB tuner, whichever works better. And when I upgrade my Dish to the 622 box, I would like to feed it since it can also time shift OTA ATSC.

I was really hoping the 5th gen tuner was going to do a better job with the weak signal and multi path, but I guess my shadow is just too big. I am also wondering if I am just unlucky and may have gotten in one of the weak lobes of signal cancellation. I was reading through some other peoples installation issues and I never thought of the combing that can occur if the signal is reaching me through differing paths. My mounting location does not allow me to easilly move the antenna north/south to see if the signal improves. I have tried, without luck so far, to borrow a signal strength meter I could use with a much smaller antenna and walk around my roof to see if I can find a better spot. Too bad my chimney is actually 4 feet lower than the edge of the upper floor roof.

I used to liver 25 miles from Chicago. I was terribly spoiled. I could see the Sears tower and Handcock tower from my roof. I aimed my medium directional antenna between them and had a rock solid signal with no amps needed. Of course 6 years ago there was not much HD to speak of.

Gary

GSMnow

I think I just found my ideal addition for VHF high band.
I can't post links yet, so
h++p: wow. solid signal *** / manuals / ya1713.pdf
let's see if that goes through the filter.
If not, I am looking at the Winegard YA1713 VHF high band only yagi to add to my CM4228 UHF antenna for post Feb 09. This is a big antenna, but it weighs in at just 3.25 pounds. That does not seem possible.

I will cross my fingers for ABC, KCAL, FOX, and KCOP to go to 7, 9, 11, and 13, none of which I can get now on their UHF frequencies 53, 43, 65, and 66.

I also noticed several channels moving to lower frequencies in the UFH band. CBS is going from 60 to 43 where KCAL is now. I sure hope I don't lose CBS. KCET (PBS) is also going to move from 59 down to there analog slot at 28. I actually get their analog feed with just a bit of snow, so maybe that will be good.

Rick0725

An alternative to consider for uhf is the 91xg which has higher gain at the higher uhf band, can be angled up easily (mounting mechanism will adjust), weighs much less than the cm4228, and will combine easily with the ya1713. Separates tend to perform better than combos especially in uhf. It appears you need the added gain.

The 91 xg antenna would be tilted towards the horizon...10-15 degrees is typical. Some channels may come in better some worse and hard to guess. The cm 4228 is going to be a challenge to tilt.

The hdp269 is a great choice for the suburbs. I mounted mine at the grounding block to take the edge off the incoming signal. Winegard just released a ch 7-69 antenna. line The largest is the HD7698P @168.25", the equivalent to the hd8200p so to speak. Separates should out perform it.

Lkr

zip 91384? i used to live in Valencia and Castaic, had problems with OTA the entire time I lived there.

otaota

If you enter your exact coordinates and antenna height into the signal analysis tool at TV Fool, you can get an estimate of what all the signal strengths will be. That might tell you if there's a real possibility of overload or not.

There's also the possibility that the amp or power supply have gone bad. Without power, amps will usually block the signal rather than let anything though.

I wouldn't worry about being that accurate. The vertical beam pattern of the 4228 is +/- about 20 degrees, so a few degrees either way will hardly make a difference. I would try to err on the side of being a bit too high. There's basically nothing coming from the ground or the mountain. All your signal is coming from the ridge's edge and the sky. I think you would be safe over-shooting the ridge by 5 degrees. You may be looking at a 10-15 degree tilt here.

This is actually quite difficult to do with the CM 4228 because of the way it mounts. The 91XG is far easier in this regard. If you are going to add a separate VHF antenna anyway, then you'd probably like the 91XG as a better UHF companion.

If you want to do some more trig, you can get the height of the mountain between you and the transmitter by loading Google Earth. You can hover the cursor over any point and it will tell you the elevation. Hint: Use the ruler tool to draw a line between Mt. Wilson and your house. The line will help you see which ridges the signal must pass over. If you have topo software like Topo USA or the National Geographic topo collections, that will work even better, but Google Earth is free and it's pretty cool.

Cheers,

__________________
Chuck

GSMnow

My zip is 91354. I am closer to a mountain and lower down than Castaic. Next time I have help over (willing to climb on the roof) I will block out the bottom of the antenna to about 5 degrees and see what it does. I should be able to just use a longer "U" boltt and a plastic or metal spacer. I will have the top of the mast just above the upper "U" bolt so the mesh can lean back over the mast. This iwll even raise the antenna another 6 inches.

I will certainly look at TV fool. Is there and easy place I can enter my adress and get the true Lat/Lon/Alt? Or I can just borrow my brother's hand held GPS.

I wonder what FM stations come off of Mt. Wilson? I could use that as a good test of signal strength of channel 7.

Thanks again for the info, I ope to have some time and decent weather this weekend.

otaota

In order to get 5 degrees above the ridge line, you might actually need more like 10-15 degrees of total tilt.

A handheld GPS is always good. That will get you within a few meters accuracy.

You can also try online mapping tools like http://www.earthtools.org/. Just keep zooming in until the cross-hairs are on top of your house. The coordinates are shown in the upper left hand part of the screen. Simply guessing the antenna height above ground is good enough.

TV Fool does allow you to simply enter an address, but for the greatest accuracy, it's better to enter actual coordinates. Sometimes address lookup engines can be a couple of houses or even a couple of blocks off, depending on the quality of the underlying databases. This is particularly important in terrain obstructed areas where a few blocks either way can make a big difference in signal coverage.

Cheers,

__________________
Chuck

GSMnow

I just used my addres in TV fool, and it looks bleak after 2/09
I will never get ABC and I will loose CBS. Fox actually disappears from the chart where I sorta had a chance on the current channel.

This chart is making me just give it up. There is certainly no reason for me to beat a dead horse once the change happens next Feb. I can't justify spending money on equipment if I can't get anything worth watching. I will still get NBC, but that is about it.

Just for the heck of it, I entered a 100 foot antenna and it does not help at all.

I will probably take the antenna down and just spend the money to upgrade my dish network package. With what I see here, any money on an amp or antenna is a plain waste.

otaota

Depending on your exact location, you may be right about having very limited options. I'm sorry if that's the case.


Cheers,

__________________
Chuck

formercanuck

I'm closer to 'old' Santa Clarita - Wiley Canyon/Orchard Village area, and I get some decent service here:
I have a 'hack' setup (Philips MANT510) 50dB indoor antenna - indoors, I can get a few channels
I put this thing on my roof (bad), and with the RCA converter box (DTV coupon/WalMart), I get the following:

2.1 (weak) -10-20%
4.1, 4.2, 4.4 (60%) - this comes in with even a cheap pair of rabbit ears indoors
5.1 (55%)
7.1, 7.2, 7.3 (weak 10-15%)
30.1, 30.2, 30.3, 30.4 (decent 30-36%)
34.1 (40%)
44.1, 44.2 (25-30%)
46.1,
50.1, 50.2, 50.3, 50.4 (20-25%, stable)
54.1 (30%)
56.1, 56.2, 56.3 (25%)
57.1, 57.2, 57.4 (25%)
62.1, 62.2 (10-15% weak)

I'm wondering what kind of setup would help, assuming I could get HOA approval for outdoors. (MANT910?) or stick a big old antenna in the attic.

deadhead68

I'll let one of the more knowledgeable people on here recommend an antenna. But, I can say that you do not need to get HOA approval for an outdoor antenna. They cannot keep you from putting one up.

Also for someone to recommend an antenna, post your ZIP code.

DeadHead68

__________________
Panasonic TC-P46X3
HR24-500
Sony STR-DG810 Receiver
Sony BDP-S360
Denon SYS-76HT Speaker System
Harmony 650

formercanuck

Zip = 91355
I agree, HOA can't stop me from putting up an outdoor antenna (already have a DirecTv dish - as do most around here). I'm looking to keep it mounted to the house and mostly transparent, and not the 50' mast I see on a few in Newhall.

formercanuck

Just as an FYI, I've moved the antenna from the edge/peak of the house to a spot 4' higher, further from the source (tree interference?), now I've got ABC pretty good, as well as KCET (18.x), and 28.x, and max out at 38 channels
eg. 30.1 was ~25% signal, and now is 35-40%.