San Francisco Antennae help

mysterons · 9-Sep-2013, 3:55 AM

I live on the south slope of Mt. Davidson and just bought vanilla Mohu Leaf to grab OTA signals. I'm able to get the San Bruno Mtn channels with no problem, but I can't seem to get the Sutro tower signals where I am. I understand that I'm using an indoor antenna and I've got a hillside behind me so the obstruction is a problem.

I'd still like to get the channels off Sutro. Based on the report it sounded like a simple antenna is sufficient.

Here is my report: http://www.tvfool.com/?option=com_wr...46aeaf39eac452

I'm open to purchasing a different antenna if it will improve in grabbing the signals and or possibly mounting it on my roof.

GroundUrMast · 9-Sep-2013, 8:51 AM

Try an RCA ANT-751 mounted outdoors. Given the hillside and the close proximity to the Sutro Tower complex, you'll need to be ready to experiment with aim.

mysterons · 9-Sep-2013, 2:37 PM

Cool, I'll give that one a try.

Also, since I was previous DirecTV customer, is it safe to use the same cables that are already in my house to connect to the antenna, granted I take off the power supply?

GroundUrMast · 9-Sep-2013, 5:06 PM

The cable is no doubt RG-6/Q (quad shielded) and will work fine for OTA TV. But as you have said, the satellite system accessories will need to be removed to allow the lower OTA frequencies to pass.

mysterons · 27-Sep-2013, 1:38 AM

All right, so I got my RCA ANT-751 and aimed it in the general location of Sutro Tower (north). I can get KGO pretty well and KTVU comes in and out (probably more trial and error is needed). However, all the other channels, like KPIX, KQED (9), CW, KRON are not coming in.

Any suggestions?

StephanieS · 28-Sep-2013, 11:47 PM

Some questions:

Do you have obstructions around the antenna?
How long is your coax run?
Are you splitting the run to multiple TVs?
Did you use the dish style roof mount included in the box or is the ANT751 on a pole more than 2' above the roof?
Did you use the provided 300 to 75 ohm Transformer from the ANT751 box?
(I ask because some have noted the provided transformer isn't of the highest quality)

I use an ANT751 as part of a two antenna set-up. The ANT751 shoots locals exclusively and a Idaho PBS translator at 55 miles. All signals I use the ANT751 for I am LOS with. I've been really satisfied with it.

Now to your situation. I agree with the suggestion to try the ANT751 first. It should provide you all the major networks in the bay area. Even though you have 1-edge to contend with, you are so close to the transmitters, you should have reasonable signal access at magnetic 352.

Before I suggest you try anything different without knowing the particulars of your set up, I'd further work with aiming. With your strengths available, pointing the ANT751 at about 50 degrees magnetic would be where to start, trying to find a sweetspot between towers that yields all signals. That spot should exist.

I originally had my ANT751 on the dish network style mount. When I went to a two antenna system, I tossed that mount and went to real pole. My ANT751 now sits 25' above ground (5' above the roof) and has clear LOS to the NW, W, SW and S. I've found the ANT751 works best when it has the LOS to work with.

That said, let's get a few more details of your set up before I offer anymore thoughts.

mysterons · 29-Sep-2013, 3:09 AM

Quote:

Originally Posted by StephanieS

Some questions:

Do you have obstructions around the antenna?
How long is your coax run?
Are you splitting the run to multiple TVs?
Did you use the dish style roof mount included in the box or is the ANT751 on a pole more than 2' above the roof?
Did you use the provided 300 to 75 ohm Transformer from the ANT751 box?
(I ask because some have noted the provided transformer isn't of the highest quality)

I use an ANT751 as part of a two antenna set-up. The ANT751 shoots locals exclusively and a Idaho PBS translator at 55 miles. All signals I use the ANT751 for I am LOS with. I've been really satisfied with it.

Now to your situation. I agree with the suggestion to try the ANT751 first. It should provide you all the major networks in the bay area. Even though you have 1-edge to contend with, you are so close to the transmitters, you should have reasonable signal access at magnetic 352.

Before I suggest you try anything different without knowing the particulars of your set up, I'd further work with aiming. With your strengths available, pointing the ANT751 at about 50 degrees magnetic would be where to start, trying to find a sweetspot between towers that yields all signals. That spot should exist.

I originally had my ANT751 on the dish network style mount. When I went to a two antenna system, I tossed that mount and went to real pole. My ANT751 now sits 25' above ground (5' above the roof) and has clear LOS to the NW, W, SW and S. I've found the ANT751 works best when it has the LOS to work with.

That said, let's get a few more details of your set up before I offer anymore thoughts.

Thanks for your reply.

I've snapped a few photos of my setup that are posted here: http://imgur.com/a/ImCor.

And now to answer your questions:
1. My house is tall, estimating 30' from curb. As you can see that my antenna is aimed towards the hill side in the general direction of N where Sutro tower is. I used a magnetic compass and TV fool report to get it approx 352. Another picture shows that that back of the antenna is facing the San Bruno Mtn towers.

2. Coax is approx 30' to the main TV and 20' to the second tv (10' slack and 10' per level)

3. I'm using a 3-way. I have another room where no TV is connected at the moment.

4. I am using the mount from my Directv installation.

5. I am using the transformer that came in the box.

mysterons · 29-Sep-2013, 3:11 AM

Thanks for your reply.

I've snapped a few photos of my setup that are posted here: http://imgur.com/a/ImCor.

And now to answer your questions:
1. My house is tall, estimating 30' from curb. As you can see that my antenna is aimed towards the hill side in the general direction of N where Sutro tower is. I used a magnetic compass and TV fool report to get it approx 352. Another picture shows that that back of the antenna is facing the San Bruno Mtn towers.

2. Coax is approx 30' to the main TV and 20' to the second tv (10' slack and 10' per level)

3. I'm using a 3-way. I have another room where no TV is connected at the moment.

4. I am using the mount from my Directv installation.

5. I am using the transformer that came in the box.

StephanieS · 29-Sep-2013, 4:12 AM

Thanks for the pictures, they are really helpful.

By the way, fantastic view! My family lived in the bay area (Mill Valley and later, Mountain View) from 1966 to 1978. Always loved the rolling hills of the bay area. Still come down to an A's game when I can. I digress though...

You are pointing literally into a hillside mere feet from your antenna. Is that the heading you need? If so, the ANT751 doesn't have much chance to catch a signal there. Do you have the ability to raise it up at all or are you bound by a homeowners agreement? If you can't go higher, the ANT751 is probably the wrong antenna for your application in my opinion.

Is that hillside the ANT751 pointing at on your property? If so, I might go pick up a 100' drop of coax and climb up near the property fence with the yellow house and see if I can get a better line of site then temporarily place the ANT751 10' above ground and see what it receives, that'll give you a chance to capture more signal.

The key to your successful reception is giving the ANT751 or a higher gain antenna the best shot at catching the most signal.

I don't want to get into a discussion about any other antennas at this point because due to the close proximity of that hillside, even a high gain antenna is going to struggle to capture signal.

Your first order of business is getting higher either on your roof or using a higher point on the property that has better signal access.

mysterons · 29-Sep-2013, 1:22 PM

Thanks for the reply.

I thought about getting a longer mast, so I guess that is worth a try. My property is close to where the yellow house is. Funny thing is that that isn't the peak of the mountain. I'll have to survey the next block over to see if there are any obstructions.

The antenna is pointing towards Sutro at the moment, which is directly into the hillside.

ADTech · 29-Sep-2013, 4:33 PM

Since there is no signal coming through that hill, aiming the antenna into the hill is not a useful exercise,

There are only two ways that signal *might* reach your rooftop location: 1) Diffraction - bending over the hill or 2) Reflection -bouncing off a more distant object (hill, building, tree) back to your location.

Neither is going to be easy or reliable. To check for diffracted signals. you must work the contours of the visible skyline with the antenna aim, adjusting azimuth and elevation as needed. To check for reflected signals, aim the antenna in the (generally) opposite directions at various physical objects and see what you might get.

Do not be impatient and don't be too optimistic. Your area is known for being anywhere from merely difficult to impossible.