Originally Posted by MLaurel
I have a Antennacraft 5884. Even though the signal strength on KERA is around 58, it holds pretty steady most of the time with little fluctuation. We watch KXAS and KTVT a lot so there's a lot of complaining and cursing when they start dropping out. KXAS is currently fluctuating between 39 and 44 with occasional audio drop out and pixelation. KTVT is currently fluctuating between 34 and 40 with frequent drop outs which is a huge disappointment because it means watching Hawaii Five-0 will be a challenge at the very least. KDAF is holding pretty steady at around 59. When I moved the antenna to the roof I tried bypassing the amp but didn't get any signal to speak of on KXAS, KTVT and KPXD. So, yes I am going through an amp. Do you think it would help to point the antenna a few degrees more to the south?
Well, let's see. Let's forget about KERA for the moment. They are having some issues that will hopefully be resolved soon. We can come back to them then.
At first glance the 5884 looks good on VHF but a little weak on UHF, which may explain your problems. (It was probably designed back in the "analog era" when folks didn't care about UHF as much.) I'm guessing the direct path from Cedar Hill to your home is partially blocked. If so, a reflected signal may be nearly as strong and may interfere with the direct signal. I know that's a lot of "may's" but since the signal levels are not only weak but also fluctuating I think I'm on the right track.
Yes, the easiest thing to try is to rotate the antenna. Move it toward the south a bit and recheck all the troublesome stations. If you get improvement on most of them, move it a bit more and check yet again. If things get worse, try moving the antenna in the other direction. There's a lot of trial and error involved, but the idea is to find the orientation that maximizes one signal relative to the others arriving at your antenna. (One more thing: you may have to re-tweak everything in May after all the trees leaf out.)
If that still doesn't help enough, check all your cables & connections. You may have nothing more serious than a bad cable or balun! Try connecting a portable battery-operated TV in place of your amp; if things are OK there, there's a problem "downstream" somewhere and you can keep moving the portable TV downstream until you find where the signal goes bad. If things are still bad at the amp, move upstream instead.
If you can't get a good signal even on the roof using nothing but your antenna, a short cable, and a portable TV (only try this in good weather, please!), then the only things left to try are moving the antenna or replacing it. Moving the antenna will change the relationship between the direct signal and any reflections, which could improve your signal considerably.
If nothing else works and you decide to replace the antenna, you will get plenty of good recommendations on this board! Since we don't have VHF-Lo in DFW my personal favorites are: the Antennacraft HBU series (even an HBU-22 should work where we live), available at Radio Shack; the Channel Master 2018 or 2020, available at Fry's; or the Winegard 7696 or 7698, also at Fry's. The Channel Master 4228HD (Fry's again) is also good, but it's a panel-style antenna. It's a bit weak on VHF-Hi but should be adequate for WFAA and KFWD, which have relatively strong signals in Garland.