Question: Point indoor antenna to pickup CBS/FOX in San Francisco

U

Unregistered

Guest
#1
I've been trying to do the online research to find the answer myself but I'm not able to find exactly what I need. I have a 'radio shack' brand indoor UHF/VFH antenna (Cat. No. 15-1868) http://support.radioshack.com/support_video/doc69/69559.pdf connected to an older 42" Vizio LCD TV.

I am on the uphill side of the street about 1/2-way up a hill near 25th and Guerrero. 25th and Guerrero, san francisco, ca - Google Maps
My windows which are near the TV face East, it appears that the towers I'm trying to reach are on Twin Peaks which is behind me to the West. I don't have a way to put the antenna in the back and run a cable to the living area.

Here is my TV Signal Analysis from the TV Fool website
TV Fool

I'd like to get the basic major networks (ABC, NBC, CBS, FOX). Right now I'm only getting NBC and ABC and a few other smaller stations. While it may not be possible to get these channels w/o having to get a lot of equipment, install anything on the roof, etc...

So, can I use the equipment I have? Which direction do I need to point it? If I can't use the equipment, what recommendations for internal hardware do you have that might make this work.

Thanks for the help.
 

Fringe Reception

Super Moderator, Chief Content Editor
Staff member
#2
Guest,

I'm a little surprised you aren't receiving CBS and FOX and my guess is you are receiving too much signal, which is confusing your tuner. As a test, how about removing your Radio Shack antenna and insert a straightened paper clip in the antenna socket, then scan for new channels.

This was first suggested to me by a TV Station Engineer and I thought he was nuts, but I have done it and sometimes it works. Please let us know what happens.

Jim
 
#3
I find it interesting You have trouble with CBS and FOX just like I do even though you are 60 miles closer. We both can get ABC and NBC easily though.

ABC and NBC are VHF; while CBS and FOX are UHF for one thing. Maybe that affects the propagation?

Sutro Tower Link : http://sutrotower.com/

Here is the map showing the transmitter location, Sutro Tower: Sutro Tower Inc
1 La Avanzada Street, San Francisco, CA, Map : Google Maps

Can you see the transmitter tower, by line of sight do you think? Maybe you are not high enough on your particular hill?

I think it has something to do with CBS and FOX being UHF. Curious what others have to say.

Here is the antenna configuration on the Tower: http://sutrotower.com/tower-technology/
 
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SWHouston

Moderator
Staff member
#4
I think this situation would be a good candidate for a...RCA ANT1400 Multi-Directional Digital Flat Indoor TV Antenna (ANT1400) from Solid Signal. Get a 10-15' Coax and connect it to the 1400, and move it around the closest walls. When you get the best reception, hang it high up on the wall and enjoy. Use your channels 44.1 & 65.1 to do the signal reception strength test. If you can find a place where both of those receive well, then that's it ! However, if you have to choose, I think I'd go with the 44.1.
 
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nbound-au

The Graveyard Shift
#5
Guest,

I'm a little surprised you aren't receiving CBS and FOX and my guess is you are receiving too much signal, which is confusing your tuner. As a test, how about removing your Radio Shack antenna and insert a straightened paper clip in the antenna socket, then scan for new channels.

This was first suggested to me by a TV Station Engineer and I thought he was nuts, but I have done it and sometimes it works. Please let us know what happens.

Jim
Agreed, another possible problem could be multipathing due to strong internal reflections from your own building.

Ideally placing an antenna outside would be best. If you are on the top floor, having it in the roofspace may help.
 
#6
Guest, your location on the street shouldn't matter unless TVFool is misfiring out the keister! It says you're line-of-sight to many powerful signals even though your antenna is only 5' off the ground, and the hill you're concerned about seems to show up on the terrain maps.

Your building may be causing the problem. It sounds like you're in an apartment on the east side, and there are more apts. to the west between you and the tower(s), is that correct? Either that, or Fringe is correct that you have too much signal, probably bouncing all over the joint, and that's confusing the tuner.

Definitely try the paper clip first. Too much signal, or too little: the answer to that will dictate the solution* to your problem.

Rick

*If a solution exists, it will probably not be in the form of an indoor amplified antenna.
 

MrPogi

Moderator, , Webmaster of Cache Free TV
Staff member
#8
Maybe the problem isn't JUST that the signal is too strong. I suspect that there may be whole lot of building between the poster and the Western towers, blocking the signal as nbound-au suggests. Also, the two channels poster says he gets are both VHF, AND the NBC channel is to the East.
My windows which are near the TV face East, it appears that the towers I'm trying to reach are on Twin Peaks which is behind me to the West.
Guest, Could you tell us more about the building you are in - what is its construction, and how many walls are between your antenna and the transmitters to your West? Are there other buildings that could block your signal between your building and the West towers? Is there any way for you to put an antenna to your West, perhaps outdoors with a cable fed through a window?

Your rabbit ears will work well for your VHF channels (real channels 7 and 12), but they are not very good for UHF, where most of your other channels are.
 
#9
Guest, your location on the street shouldn't matter unless TVFool is misfiring out the keister! It says you're line-of-sight to many powerful signals even though your antenna is only 5' off the ground, and the hill you're concerned about seems to show up on the terrain maps.

Rick
I was able to finally figure out how to do an elevation profile.

What it showed is: There is no Line Of Sight! It is blocked by a hill.

I used these tools (so someone else can re-create the profile, or do another for their own situation) Really interesting application IMO!

Elevation Profile In Google Maps

HeyWhatsThat Path Profiler

Input two data points, 25th &Guererro and Sutro Tower address:

37.755362° N 122.452577° W 869 ft
102° 1.7 miles 2 total
37.750369° N 122.422783° W 144 ft

Sutro Tower to Guest's Home

profile.cgi.png

Sutro Tower to Mine

profileSutrotoMyHouse.cgi.png
 
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#10
I was able to finally figure out how to do an elevation profile.

What it showed is: There is no Line Of Sight! It is blocked by a hill.
Okie, I appreciate you finding those apps and doing the profiles, but what you say just does not compute! I know you have no line of sight to the Sutro tower, but clearly the OP does, unless trees, or his own building are in the way.

TVFool has this type of profile built right in. All you need to do is bring up our guest's TVFool report, then click on any of the stations where a LOS path is indicated. A terrain map pops up. On most of our guest's TVFool terrain maps, you can see just the same features as appear on your "Sutro Tower to Guest's Home" graphic -- the only difference being, the Sutro tower is shown broadcasting from a much greater height than in your graphic!

Here's my suspicion: According to Wikipedia, the Sutro tower is 977 feet tall. I think this is 977 feet in addition to the ~900 feet in your graphic, which just reflects the terrain at the base of the tower.

It's hard to believe TVFool got all those LOS readings wrong in this common situation, so maybe the height of the tower explains it. Bear in mind, the TVF reports can not, and do not claim to, take a user's building into account, nor any nearby trees.

I really have a feeling our guest's situation is a lot different from yours. :dizzy:

Rick
 
#11
You're right, the tower elevation is wrong on my chart. Should be 1800. Looks like that would easily put it in the clear.

"Sutro Tower is 977 feet high, with a base elevation of 834 feet, so its highest antennas are 1,811 feet above sea level."
 
G

Guest

Guest
#13
Hello everyone. It's me, 'unregistered guest'. Thanks for your patience. I'll try to answer the ?s posted.

I tried the paperclip and while I got some channels, I got fewer than before and did NOT get FOX or CBS.
I do not have a clear view to the Sutro Towers, they are behind me. I sit about halfway up the hill on the uphill side. The house is pretty long and the TV is near the front (street side). One of the questions was how far the antenna is off the ground. Well, that's tricky to answer since i'm on a hill. If I draw a straight line out and then down to the street level it's probably ~40-50ft. Since we're on a hall, it's perhaps only 25 to dirt below me. As for where it is in my actual apt, it's about 4' off the ground. Hope that helps.

Their is another tenant on the floor right above me. The walls are plaster but there are massive bay windows right near the TV and directly by the antenna.

I did try the RCA Digital Flat Antenna (ANT 1650R) Amazon.com: RCA ANT1650R Flat Digital Amplified Indoor TV Antenna: Electronics That didn't seem to work. to pickup the UHF channels I'm missing.

Could it be an error while I'm scanning? I tried to manually look for a particular channel but that didn't work. The RCA antenna linked above seems about the same as the one I got which didn't work.

Perhaps the added data points I provided would help provide new suggestions?
 

SWHouston

Moderator
Staff member
#14
Unregistered, Sorry that RCA didn't work, I thought of that type because of the seemingly strong signals which Jim noticed as well. That particular type usually works well in your situation. You say that the Towers are behind you to the West. Does that mean that they are above you as well ? IF that's the case, could you mount an Antenna on the side (outside wall) of your residence toward the Towers, and maybe point it upward some ? And IF that can be done, take a look at these Antennas, which several can be wall mounted. The Antennas Direct C1 may be a good candidate.
 
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#15
I tried the paperclip and while I got some channels, I got fewer than before and did NOT get FOX or CBS.
So you need more signal, not less.

I do not have a clear view to the Sutro Towers, they are behind me. I sit about halfway up the hill on the uphill side. The house is pretty long and the TV is near the front (street side).
"Uphill" ... "Behind" you ... No way can I visualize this without a diagram or somesuch. It doesn't matter what you can literally SEE with your eyes. Can't you please just tell us what is between you and the towers to the west other than that hill? The TVF report should be taking the hill into account, since you input your exact address. It's conceivable TVF is screwing up, but you still haven't told us directly if there's a wall (or two ... three ... four walls) between your antenna and the west side of the building!

RF signals don't automatically pass through your average wall.

One of the questions was how far the antenna is off the ground. Well, that's tricky to answer since i'm on a hill. If I draw a straight line out and then down to the street level it's probably ~40-50ft. Since we're on a hall, it's perhaps only 25 to dirt below me. As for where it is in my actual apt, it's about 4' off the ground. Hope that helps.
Well, you had 5 feet in the report, and higher would only improve the signal, so that's not the problem.

Their is another tenant on the floor right above me. The walls are plaster but there are massive bay windows right near the TV and directly by the antenna.
Doesn't matter in the least unless the windows are on the west side giving LOS to the tower. The signals go in a (nearly) straight line, and they don't like obstructions. :dizzy:

Could it be an error while I'm scanning?
Sure! Could be any link in the chain. Could just be a bad TV.

I tried to manually look for a particular channel but that didn't work.
There's a trick to that, too. Your TV doesn't know the virtual channel numbers, which are the channels we normally think of. You have to tell it to look for the RF channel number, which is listed in your TVF report. The exact procedure is different for every TV. (Crazy way to run a railroad, IMHO, but that's what the digital transition left us with.)

If we knew for fact there's multiple walls between you and the tower, and you can't get a better position for your antenna, at least then we could tell you it's hopeless. :flush:

Rick
 
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#16
I think the guests apt is on the east side of the building and faces east; while the Sutro Tower is off behind to the west. There's other apartments on the west side of the building and if you were on the third floor looking out of one of those windows you might be able to see the tower. Also depends how far up it is on that particular hill that Guerrero is on. 25guerro.jpg

Google Maps

Maybe that big red-roof building in the satellite.

When I asked if guest could see the tower I think I meant if he was on the street in front of his building looking west could he see it over the top of the apartment building. I was trying to get at relative elevation angle, if you know what I mean. Like how tall is the building relative to the elation angle to the Tower.

I would try a test by putting a long coax on the indoor antenna and attach it to a pole and stick it out an open window, or pass it to someone else out on the street level. Point being to see if it is outside can it pick up those uhf.

Seems UHF is blocked much more easily than VHF.
 
#18
We weren't really clear that he was in a apartment at the beginning. Now we know that, and his antenna is 4' off the ground, also his windows face east. So best guess: he has at least two apartments between himself and the west side of the building and at least two floors above him. (I'm looking at those buildings in the picture as best case scenarios.) Therefore, he's going to have a tough time getting a signal that doesn't have to pass through three walls.

From the terrain maps, he probly can't see the base of the Sutro tower from the street, but can see the top of the tower on a clear day, which would be hard to recognize. But the poor antenna can't see nuttin. :daffy:

I have three crazy ideas:

1) Tell the landlord he has to get a roof antenna!

2) Bribe one of the neighbors on the west side. Put an antenna in a west facing window and get a long stretch of RG-6. Awwwww ... Landord might not like coax winding through the hallways.

3) A ground antenna?!? Laugh if you like. I get a 100% stable signal on three Milwaukee stations (UHF below RF30) with the little screw in my AC outlet. There are two rooms between me and the north (Milwaukee) side of the building.

Rick
 
#19
OK, if he has a socket connected to ground, he might be able to get these stations:

Stat RF Network
KPIX 29 CBS
KOFY 19 ?
KQED 30 PBS
KGO_ 07 ABC
KNTV 12 NBC
KTSF 27 Ind
KFTL 28 ?
KTNC 14 AZT

In addition, with an antenna in the east window, if there isn't another apt. building directly to his east, he might get a half dozen more stations, even possibly KTVU RF48 which is a Fox station at 25.9 NM.

Rick
 
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