Entertainment Center: TVs, Stereos, VCRs and DVDs - Poor UHF reception

I am not getting satisfactory reception of UHF stations using my rooftop TV antenna. I have tried rotating it a few degrees, and I can get minor improvement of UHF, but the adjustment seems to degrade the quality of my VHF reception which usually comes through just fine. I added a 10 dB amplifier / splitter which only seemed to help a bit. I am located in a Dallas suburb with no major obstructions that I can see between my house and the broadcast sources.

Would upgrading my antenna help my UHF? If so, do they make one with an independently adjustable UHF element? Any suggestions?

Also: I noticed that the coax cable from the roof antenna runs to a small connection plate mounted on the side of my house. From there it runs into my attic. A ground wire also branches off from this plate and contacts the galvanized pipe that comes out of the ground and into my electric meter. The wire is bare, and seems to be aluminum.

Before I invest in a nice TV; is this sufficient ground in case of lightning strike? Is it okay to use the downlead to ground?

UHF is the hardest signal to receive for television. It attenuates more per foot of downlead than VHF, and it is usually a weaker signal when it gets to the antenna in the first place. You can get a UHF only, and a VHF only antenna, and then aim them each for best reception. More importantly, I would try to find a higher gain amplifier. Radio Shack used to have them with about 30db gain in the UHF band, but much lower gain in VHF. Some companies make a UHF only amplifier, but that is more of a specialty item so you would find that at a large electrical supply store. The might have to special order it.

Check out the TV antenna FAQ on this site, under "Repair/Fix-it", then "Electrical".

It's hard to tell if the ground you have is sufficient. If it is hooked up through a proper grounding block, then that's about as good as you can do. A direct hit will cause major damage no matter what. In Texas, I would consult people who do lightning protection as a business, they'll know if there is anything more to be done. Make sure the contacts are clean and uncorroded on that aluminum wire.

Hi Ranck,

Thanks for the info. I also learned a lot from the antenna FAQs.

Few more questions: If I add a new UHF only antenna next to my existing UHF/VHF antenna, then combine the cables leading from the two, will my picture quality for UHF stations still be okay? Do I need to invest in a VHF only antenna as well in order to get good reception on the UHF?

Good evening, albert:
UHF is the dinosaur of television signals and my counterpart, ranck, did a good job of delivering information.

First, UHF frequencies are ABOVE cable television and reception is limited to "line of sight". Your antenna must actually "see" the transmiting antenna to get any clear reception. This is not always possible in many areas and, hence, the demise of UHF has been paramount.

You can stack antennae where as you can put two antennae on a mast and wire one to another. This will improve gain about 3 dB (or twice power level).

You need to use cable (either flat lead or coax) that will handle the ultra high frequencies. Some cable is only designed to work at Cable-TV frequencies. If you put in a splitter, the splitter must be broad-band and live with the ultra high frequencies. Any amplifier you buy must be capable of handling the ultra high frequencies.

It's a dying field that has been around for a few decades. New technologies and new lower channel applications are overshadowing the UHF band. You have to buy special wire, special connectors, and special antennae for this application. All are getting rare.

Smokey

You might be able to combine a UHF only antenna with your existing VHF/UHF. It might cause ghosting, or it might help. This will be determined by the length of the wire connecting the two antennas. If the UHF signal from the two arrive in sync with each other, then you just get more signal, but if they arrive out of sync you get ghosting. The technical term is "in phase," and the lenght of wire required is dependant on the specific frequency of the UHF channel. Without going to a lot of trouble, it's probably easier to just try it and see what happens. A little trial and error with cable length and you might be OK.

By the way, Smokey, those UHF channels are getting re-used. That's where the FCC is putting the new HDTV simultaneous transmissions.