If you have one antenna connected to an HD TV and put a splitter in to add another TV the signal is weakened. Can you attach a new cable to the antenna along with the old one without weakening the signal?
Or --- you can add a splitter amplifier.
hmm Sure i do
You only have 1 connection terminal at the antenna ?? if your antenna has a 2-screw balanced 300-ohm connection, sure, you can use a second balun for a 2nd coax. If it's one female F-connection, you will have to use a splitter somewhee for a 2nd TV.
The thing with digital HD is that if you don't see pixeling effects (square blotches) on the screen, the signal is strong enough (or your TV Tuner is sensitive enough to receive a marginal signal).
Signal strength degrades by using a splitter, but also by long coax runs. Just determine whether your signal is so marginal that losing 3db will result in pixeling before you fuss about splitters.
No. Period. You cause an impedance mismatch when you do that and it will result in a 6dB signal loss to each cable, plus the extra cable loss.
The first thing to do is make sure you have the right antenna for your area. Go to this web site to find the best antenna for your area.
This web site helps select an antenna that is capable of powering one TV, but many of us have multiple TVs or TVs and a recording device or two. You can upgrade to a more sensitive antenna, but that will usually result in a more directional antenna and you could lose stations because of this. You can get a rotator to get all the stations, but those can be a hassle.
You also have to be careful that the antenna selected will pickup all stations. Many areas of the country still have one or two stations on the VHF band, sometimes one on the lower VHF and one on the upper VHF. Some antennas that claim to be VHF/UHF will only pick up VHF stations in the upper band (channels 7-13) and not the lower (2-6).
For multiple TVs or TV(s) and recorders (DVR), I recommend the following. First check the above site for the channels in your area and what frequencies they broadcast in. The channel they use to identify themselves is not necessarily the channel they broadcast on anymore. In my area, 5.1 still broadcasts on the old channel 5 frequency, but channel 3.1 broadcasts on UHF channel 28. Only a roof top antenna will pick up channel 5.1, all the small indoor HDTV antennas are UHF only and a few indoor/outdoor antennas are upper VHF/UHF and since channel 5 is lower VHF, they won't work.
Now you can get a amplified antenna or passive (non amplified) antenna. I recommend the passive antenna. The web site above gives you distance and direction to the various TV stations in your area. If you live an a rural area, you may need a higher gain, more directional antenna, but all your TV stations will be about the same angle so the directivity will be an advantage, it will help eliminate interference.
If you live in a metropolitan area, the TV stations will be all around you so you will need a lower gain, more omni directional antenna. You need the lower gain to keep from overdriving the receiver in the TV set.
Now if the selected antenna will only power one TV and you antenna is outside or in the attic (you can mount an outdoor antenna inside your attic if there is enough room), you can add an amplifier. I prefer the remote power amps that mount just below the antenna. You plug in the adapter at the TV end or distribution end of the coax and the power is supplied through the coax to the amplifier. No need to run an outlet box up on the antenna mast. The adapter has eh power plug and two coax connections, one goes to the antenna amp and the other goes to either a TV or to a splitter.
The advantage of the antenna mounted amplifier is that there is signal loss along the length of the coax and a small amount of noise that is picked up by the coax. You want the highest signal to noise ratio that you can get for a clear signal and that means putting the amp where the signal is the strongest and the noise the weakest. I like these Blonder Tongue products, they commercial equipment as well as consumer grade products for the TV industry.
This link shows the installation, click on the tab "specifications" if it is not already highlighted.
This one is a good one and one of the easiest to install. It is best for antennas that combine the UHF and VHF on the same terminals. Scroll down to see how it installs.
Last but not least, you can go to Radio shack and get a 4 port distribution amp. This will mount at the end of your current coax so it is the easiest to install, but should not be used if the coax from your antenna to the amp is over 100'. It really is most suitable where the coax from the antenna is pretty short.