What has gone wrong? Antenna? Tuner?

[PJ Corey]

I have an HBU33 outdoor Antennacraft. Until recently I was able to get over the air digital broadcasts on all four of my televisions on stations 38 miles away in Albuquerque.

I have two older tvs with converter boxes and two are new televisions with internal tuners.

Suddenly, I lost three PBS stations on my new televisions but they were not lost to the older tvs with converter boxes. In fact, I not only lost PBS (ch. 5 and 9) I also lost ch. 2 and 4, as well, on my new tvs. Adjusting the antenna on the roof did no good. If I put rabbit ears on the new televisions I pull everything in again. What is wrong??

[tigerbangs]

Are you using any preamplifier or distribution amplifier with that HBU-33? If you are using only a splitter, than I would have to believe that your problem is inadequate distribution, in which case, an amplifier like a Channel Master CM3410 installed in the line before your splitter should help you. My second guess is that the balun transformer on the antenna that converts the antenna from 300 ohm to 75 ohm (to coaxial cable from the antenna terminals) may have gone bad: this piece is cheap and easy to replace: I would start with the balun transformer, and consider the distribution amp if replacing the balun doesn't help. Also, be sure that your antenna is aimed properly: it may have drifted in the wind since you installed it.

[PJ Corey]

No preamp. Wind is a real issue here in the Southwest but since the tvs with converter boxes were not affected by the wind I am going with your other two suggestions. Thanks for the ideas -- I will pursue them.

[PJ Corey]

One other question: why would I be able to get all channels on the tvs with converter boxes but not on the tvs with internal tuner? That is what I don't understand. thanks again.

[LovesTheOTA]

I'll take a stab at answering that. My guess is the cable run is longer to the tv's that are misbehaving. The longer the run the more signal loss you'll experience. Using a distribution amp or a preamp should take care of that. As a free test you could take one of the bad tv's to the location where you have one of the good tv's and see if you're channels come back. Then you'll know for sure.

[PJ Corey]

thanks. Tried that and there was no difference. The furthest tv from the antenna is about 35'. It is on a converter box and pulls in all the channels. The closest to the antenna has a digital tuner and doesn't get 2, 4, or 5.

[tigerbangs]

If you don't have a preamp and don't have a distribution amp, then you need one or the other if you are running 4 TV sets from one antenna, plain and simple. Consider a Winegard AP-8275 or a Channel master Titan 7777, and be sire to mount the preamp's power supply in the line before your splitter: many splitters won't pass the DC current from your power supply to your preamp.

Be sure to rescan your TV tuners after installing the preamp to find oyur missing channels.