Somewhat long technical question

[Jakebert]

After spending a few hours yesterday morning fine tuning two spliced together OTA antennas, I was finally able to pick up the OSU/Michigan game on my main television. This morning I dragged the antenna wire back to the tv card on this computer and ran set up again with the antennas still in their new location. I was still picking up the ABC and Fox stations with a strength of 98 percent. I could not pick up the NBC stations as they had 0 strength based on the direction of the antenna. That wasn't a problem.

Then I realized that I forgot to attach the in-line amplifier to the antenna, so I disconnected the antenna from the computer, attached the amp, and reattached the antenna. The tv card was still cycling through the channels to determine signal strength.

Here's the part I don't understand. After the amplifier was attached, my signal strength for the FOX channel dropped from 98 to 0 and the signal strength for NBC went from 0 to 58. I'm in southeast Columbus. FOX is to the West of me and NBC is to my north. It's as if the amplifier had reoriented my antennas and my initial thought was that perhaps the electrical field from the amp had skewed the antenna reception but that really doesn't make a lot of sense considering the antennas are almost 40 feet away from the computer and amp. Plus the actual power provided by the amp is minimal.

I've read the pros and cons of amps in the forums and I just assumed that although they may not be needed, they would do no harm. Now I'm finding out that the amp may be the source of my problems in trying to pull in FOX and ABC.

Is this just a fluke of some kind or can someone explain to me why an amp would skew signal reception? Any facts or theories are appreciated.

[rossl]

Is this just a fluke of some kind or can someone explain to me why an amp would skew signal reception? Any facts or theories are appreciated.

It amplifies the noise along with the signal. The amp adds noise of its own and can get overdriven if there is a strong TV or FM station nearby. If you don't need it, then don't use it.

There is no substitute for antenna height. Getting the antenna higher up is much better than using an amp.

[scgalena]

Jakebert, am I understanding correctly that you've spliced two OTA antennas together for digital reception in your system?

[Jakebert]

One antenna sits the on north side of the house facing northwest. The other antenna sits on the north side of the house facing southwest. The antennae are mounted on the back of the house and they do not have enough height so the house actually blocks the signal if I go with one antenna and just rotate it. I would have responded sooner but forgot all about asking the question until siitng here watching De Bears and the Vikings on Fox. Apparently, without having the proper height I wouldn't be able to view the game with a single antenna without moving it to the front of the house.

[Timcredible]

someone correct me if i'm wrong, but isn't fox and abc on one tower, cbs and nbc are on another, and the towers are about 1/2 mile apart, both downtown columbus. osu is in westerville, 53 is in circleville, and 51 is where? so, you should be able to get abc, fox, cbs, nbc by pointing your antenna in one direction.

[scgalena]

Jakebert have you considered something like the Channel Master Join-Tenna for the second antenna?

Sure would beat the hassles of a rotator. If it works like the ad says? In theory, it should help minimize any multipath issues as well.

http://www.warrenelectronics.com/Antennas/joiners.htm

I have put off solving the same sort of problem up here to the northeast of Columbus as the OSU tower to us is close to 90 degrees to the west of the downtown towers.

If you should decide to try a Join-Tenna or similar device please be sure to let us know the results, good or bad.

[Jakebert]

ABC and Fox are on one tower. In fact, I just noticed the tower the other day as I was staring at it while driving down Frebis Ave. According to Antennaweb.org, their tower is the closest tower to me (2.6 miles) and I live on Frebis so I have a straight shot at the Fox/ABC tower. Yet, it was the hardest signal to pick up. I could pick up Chillicothe and Newark (channel 51) with no problem. Yet, the Fox/ABC signals are much stronger if I orient one of the antennae a few degrees away from the tower. I don't know why that is but all channels are coming in great right now so now that it's no longer broke, I'm not going to attempt to fix it any more. As far as joining the two anteannae, I'm just using a standard four Dollar coax coupler from Radio Shack - the type you would use to split a cable signal to two tvs.