TV picture quality problems

Subscribe to cable. There is only so much you can pull out from the air, unless you can expand your antenna system. Using more amplification will only increase noise, if the signal is not good to begin with.

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JANA _____

I do NOT have a cable system nor a satellite ("dish") system.

Except for small "dish"-type antennas, the condo-rules allow "yagi"-type antennas only in the attic of each house. But, knowing how much signal is lost by attic-installation, my Terk TV38 antenna is laying on a flat roof (so it's not too conspicuous to the condo-board).

A coax cable runs across the roof for 15 feet, goes down 4 feet into the attic and is connected to a Radio Shack signal amplifier. A coax cable then goes from the amplifier, through the attic for about 30 feet to the TV set.

Here are the channels I get:

Note: KVCR 24's tower has a compass orientation of 51 degrees and is 9 miles from my house. The towers for all of the other channels have a compass orientation of 287 degrees and are 43 miles from my house.

Call Sign Network Channel Picture Quality *

KCBS CBS 2 F KNBC NBC 4 G KTLA WB 5 E KABC ABC 7 E KCAL IND 9 F KTTV FOX 11 P KCOP UPN 13 P KVCR PBS 24 P KCET PBS 28 F KOCE PBS 50 E KDOC IND 56 G KLCS PBS 58 E

• Reception ratings: E = excellent (crystal clear) G = slight snow F = moderate snow P = can't see picture

Any suggestions on what I can do to get better reception?

snipped-for-privacy@co.riverside.ca.us wrote in news:1150081932.900592.110040 @f6g2000cwb.googlegroups.com:

The antenna is too close to the roof! You need to get it up off the roof by about 3 feet. Never mind that the roof isn't "electrically conductive." At VHF and UHF frequencies, *all* materials degrade your reception.

You dismiss an attic antenna without even trying it? Try it! I lived in Encinitas CA, about 90 miles from LA, and with a yagi in my attic I picked up Mt Wilson.

Keep all the antenna elements as far away as possible from everything (joists, roofing, pipes, chimneys, etc.). It's easy to hang it from the rafters with rope. And much easier to bring the downlead into your living space.

Hi Jim,

The Terk TV38 is a Large Uni-Directional HDTV Antenna measuring 149.75" L x 111" W x 31.5"H.

Since my "attic" is really only a crawl-space -- about 4 feet between ceiling and roof -- how can I "keep all the antenna elements as far away as possible from everything (joists, roofing, pipes, chimneys, etc)"?

Would the attic be significantly better than the flat-on-the-roof location?

Would the picture quality for all of the channels improve by getting a different antenna? Any recommendations?

Gary

snipped-for-privacy@co.riverside.ca.us wrote in news:1150131720.702983.157190 @u72g2000cwu.googlegroups.com:

Holy cow! I had no idea your antenna was such a monster. Forget what I said about putting it in your attic--it won't fit. (My attic antenna was a yagi, only a few inches high, that would fit your attic too.)

You might try (temporarily) raising your Terk antenna off the roof by a few feet and swinging it around a bit, looking for max signal. That will give you some info about how much signal you have to work with at your location.

Hi Jim,

The Terk antenna was originally on a 3-foot-tall mast on a tripod, making the main boom about 5 feet above the flat roof. To partially-comply with the condo-board's order, the antenna is now laying on the roof (one end is supported so the main boom is horizontal). I've run new coax from the antenna to the amplifier to the TV set and all of the connections are good.

I have rotated the antenna thru all 360 degrees! I even used a compass to point the antenna at Mt. Wilson. In both cases, the picture quality didn't improve.

Any ideas?

Gary

Hi Gary...

Couple of thoughts from a real old retired guy (who put up antennas way way way before cable was even thought of) if I may?

If you're truly rotating the durned thing 360 degrees with little or no effect, then there's something really wrong :)

Check your wiring/cabling. You have used a balun between the antenna terminals and the coax, right?

Being a flat roof, does it have a little wall around the edge? Perhaps with metal flashing? If so, you need to raise your antenna at least higher than that wall.

You mentioned that you have it propped to horizontal. You don't want it "bubble level" horizontal, but rather horizontal to either the horizon or to the top of the mountain, whichever comes first.

Once you work that out, you might want to experiment with height. Often a change in elevation of mere inches makes a collosal difference. Worth a try.

One more thing while I have you. If you've been forbidden to put it there, and you do anyway, but do it improperly or incompletely (no adequate ground, for instance) you may well be opening yourself up to a whole boatload of trouble should something go wrong. For instance a lightning strike causing fire, or heaven forbid injuring people. Just something to consider.

I'm Canadian, and don't know American laws, much less California laws, but maybe you have something similar. We used to have (still have in real real isolated areas where cable doesn't exist) community antenna systems. A whole apartment building, or row of town houses, or whatever would have one antenna, a distribution system, and each unit would share in the cost of setting it up, insuring it, and maintaining it. Perhaps you have something similar available to you.

Take care.

Ken

Hi Ken,

The main boom of the antenna is "bubble-level" horizontal. My house is about 850 feet above sea level and the broadcast towers are 6,000 feet above sea level on Mt. Wilson which is about 45 miles away. How do I know how much to angle the antenna?

Yes, I have the balun connects the antenna terrminals and the coax. (In fact, the balun that came with the antenna was bad so Terk sent me a new one).

There is no "wall" (little or big; with or without metal flashing) around the roof-edge. However, there are a few PVC and metal air-vents (about 1 foot tall) within 10 feet of the antenna.

The coax cable goes from the antenna, down one of the air vents, runs through the attic/crawl-space for about 40 feet then drops down to the TV set.

============

Right now, the top elements of the antenna are just barely visible above the perimeter of the roof. I really can't raise the antenna (even a few inches) because the condo-rules forbid any antennas from being on or mounted to common-area property (including roofs). Since I have no other location on my unit to put my antenna, I figure that, if the condo-board can't see the antenna, they won't know it's there.

Gary

Hi...

The top of your mountain is pretty close to 1 mile higher than your location. The curvature of the earth is about 8 inches per mile. So, you have pretty close to 30 feet left to make up to get yourself line of sight.

In other words, bubble level at your location is very wrong, you have to raise the director (the shortest bars, pointed to the station) end of the antenna considerably. I leave it to you to find out how much, but a suggestion would be to either temporarily run an AC cord up there, or get a hold of a battery operated set, hook it up on the roof, and watch it while manipulating the antenna.

Or, another way might be to get a pair of walkie-talkies, and while you on the roof play with the antenna someone else in your apartment "guides" you with the walkie talkies.

Take care.

Ken

Hi Ken,

Into a right-triangle calculator, I entered "237600" feet (i.e., 47 miles) for the "base", "5150" feet (i.e., 6,000 ft minus 850 ft) for a "leg" and "90" degrees for the angle. It computed an inclination angle of 1.19 degrees. (This is NOT taking into account the curvature of the earth).

I don't understand your "you have pretty close to 30 feet left to make up to get yourself line of sight" comment.

Rather than using a compass to measure 1.19 degrees, I will try using a portable TV on the roof or a walkie-talkie.

Thanks, Gary

Ken Weitzel wrote in news:somjg.14181$IK3.9766 @pd7tw1no:

I second Ken's suggestion of taking a small tv set up on the roof. And I agree that, from your location, the transmitting antennas on Mr. Wilson are *above* the horizon. In other words, you have line-of-sight contact between your antenna and the transmitters. (Unless you are tucked behind a hill or something.) At 45 miles, line-of-sight, you should have darn good tv reception.

When the air is clear (and I know this is hypothetical, considering air quality between LA and Riverside) I bet you can *see* Mt. Wilson with binoculars. That's the direction you want to aim your antenna.

Hi Jim,

My options are:

1) Use binoculars. (Maybe the air will be clean enough in December to see Mt Wilson from my house

or

2) Use a portable TV or walkie-talkies.

Hmmm.

Gary

Hi Jim,

My options are:

1) Use binoculars. (Maybe the air will be clean enough in December to see Mt Wilson from my house)

or

2) Use a portable TV or walkie-talkies.

Dont' rush me; I'm thinking!

Thanks,

Gary

You might try a mast mounted amp. The old adage "you don't pull the signal, you push it" should hold true. Since it is unlikely the you can run power up there, you need a coax powered unit. Many of them are. As far as I know there are no real requirements for an ATSC amp, other than to amplify 50-900 Mhz. If Terk doesn't have one maybe try Channel Master.

Even if you took your present amp and determined the internal DC requirement you could send the DC through the coax. You shouldn't even have to build anything, between power pass and power block coax filters you should have no problem setting it up.

JURB