Multiple antenna same market

[chiledog]

I searched the forums and did not find an answer to this question (sorry if it was already answered...)

In my market all the stations (but PBS) are in one location. PBS, however, is in the opposite direction. My antenna is pointed to the location with everything but PBS.

Can I install another tuner using a different antenna an pick up that last station? Since both of these are in the same market, I would like it to be seamless in the guide.

Where:
4-1 - PBS - is on tuner 3 (my new tuner).
5-1 - old tuner 1 and 2
rest of stations on old tuner 1 and 2.

Also I would assume I need to remove PBS (4-1) from tuner 1 and 2. And remove all other channels from tuner 3 (but PBS).

Thanks,
Mike

[matt91]

You should be able to do this no problem. Just as you describe, Sage will merge everything into the EPG, so you won't even know that there are different tuners involved.

[chiledog]

Cool, thanks.

Man, I remember as a kid having to use an automatic rotator to watch different channels. (of course once you changed the channel you can't watch anything else...). Technology is great.

[GKusnick]

Using a separate antenna to feed a separate tuner would work. But a better solution might be to mix the antenna feeds on the roof into a single coax run, and then split the combined feed to all tuners, so that any tuner can receive any channel. That's the way it's done in my building.

[matt91]

Interesting. What's required to mix multiple rooftop antenna's into a single coax run?

[GKusnick]

A simple mixer is basically just the reverse of a splitter: a passive RF circuit with multiple inputs and one output. I've seen installers use splitters as mixers by swapping the inputs and outputs. You can also get mixing amps that let you adjust the level of each input for a balanced output, but that may be overkill for the OP's purpose. You should be able to find this kind of stuff at shops that sell TV antennas.

[Taddeusz]

The only problem with combining multiple antennas would be multipath interference.

[GKusnick]

Originally Posted by Taddeusz

The only problem with combining multiple antennas would be multipath interference.

True, but since they're coming from opposite directions I'm guessing that will be minimal in this case.

[chiledog]

Also, I would assume you would add quite a bit of extra noise (I guess if the signals are strong enough and it is digital, that wouldn't matter much).

hmm, maybe I will try that. (I originally didn't go this way because I did not want to mess with the notch / band pass filters.).

[ranger]

When using multiple antennas it is a good idea to use identical coax cable lengths from each of the antennas to the combiner. This can provide a bit of gain to the signal.

[Fuzzy]

Depending on the frequency spread of the channels, you may be able to get a custom split-band combiner made up. I know I lucked out years ago in the seattle area. Some channels were broadcast from the east, others from the south. However, all the eastward channels were lower frequencies, and southern were higher. There was a nice deadband in between, so a simple combiner (with appropriate high-pass and low-pass built in) worked great. I had it made by Tinlee electronics.

Where are you located? Might let us check out your broadcast situation to give further guidance.

[davephan]

Do you need a directional antenna to receive the digital signals? If your close enough, you could use a non-directional antenna. If not, maybe pointing the antenna at the weakest signal would still work for the other stations. If not, then maybe partitioning the OTA channels between the tuners might be the best method and it will reduce the recording conflicts.

I found that when the digital switch occurred, my OTA reception improved. The picture used to be a bit fuzzy and some ghosting. Digital is clear. The only problem is during heavy rain, there can be some rain fade.

Dave

[GKusnick]

Originally Posted by davephan

If not, then maybe partitioning the OTA channels between the tuners might be the best method and it will reduce the recording conflicts.

I'm not following the logic of this. Seems to me that splitting up the channels between tuners will increase the number of conflicts, because there are fewer ways to tune each channel. So for instance if I have two tuners that can both receive all channels, then I can record any two channels without conflict. But if I split them up so tuner A gets half the channels and tuner B gets the other half, there will be some two-channel combinations that can't be accommodated by that scheme and will throw a conflict. The more constraints you put on the scheduler, the more conflicts you're going to get.

[davephan]

Adding tuners that are partitioned can reduce the recording conflicts. For example, if a there is only one HD-PVR on the system and a HDHomerun is added. Then the OTA HD channels are removed from the HD-PVR lineup, and the recording conflicts are reduced.

If all channels have the same chance of being scheduled, and all tuners could record all channels, then it would make sense to not partition the tuners. However, all channels do not have the same probability of being scheduled. Some channels are scheduled more than frequently than other channels. If more tuners are dedicated to the channels that are recorded the most, then the recording conflicts will be reduced.

In my case, I was getting a lot of recording conflicts with OTA channels. I added a HDHomerun, for two OTA only tuners, and removed the OTA channels on cable from the HD-PVR, and drastically reduced the number of recording conflicts. Plus if there is a cable system outage or satellite rain fade event, the locals are still recorded.

Dave

[GKusnick]

Originally Posted by davephan

If more tuners are dedicated to the channels that are recorded the most, then the recording conflicts will be reduced.

Agreed. The more tuners you have that can tune your favorite channels, the fewer conflicts you'll get. Conversely, disabling those channels on some tuners will increase your conflicts.

Originally Posted by davephan

I added a HDHomerun, for two OTA only tuners, and removed the OTA channels on cable from the HD-PVR, and drastically reduced the number of recording conflicts.

Perhaps, but it sounds like it was adding more tuners that reduced your conflicts, not removing channels from existing tuners. Or are you saying that adding more tuners caused conflicts, which you then solved by disabling channels on some tuners? I find that hard to fathom.

[Owen Brent]

I have a two antenna system with one tuner. I use two HD4228 antennas and they are pointed in two different directions. One thing to remember (actually there are many) is that when you use two antennas, the signal is cut in half if the antennas are facing different directions. Use equal lengths of coaxial from each antenna to a simple splitter (in reverse). Buy a good splitter that has low line loss. Use a preamp as close to the antennas as possible (If you need an amp) rather than an amplifier further down the line (increases signal noise). A great source for information about OTA can be found on the Digital home forum: http://www.digitalhome.ca/forum/forumdisplay.php?f=186

Having one antenna for each tuner would be ideal if the stations you are looking for are weak. Preamps can sometimes help, but they often just add noise or too much signal, which will also cause reception problems on strong stations. Always start with no amps in the system and see what you can get. Adjust the antenna for the best possible reception. Get the antenna(s) as high as possible (practical). Be safe (ground everything properly. If you need a preamp and you have nearby stations that you are having problems with, aim the antenna away from that station to weaken the signal a little. Experimentation is definitely required when playing with OTA. It took me a while, but I am very happy with just OTA and now SageTV has made everything Soooo much better. The next thing for me is to figure out Comskip so I never have to watch commercials.

Note: I use a preamp (+15 db) on my system because I split the signal to 4 different locations. I have also used over 200 ft of cable.

[sic0048]

Well I think the best solution is to run both antennas completely separately. IE they each have their own coaxial run down to the tuners and each antenna gets plug into its own tuner. Then add only the channels that come in strong on each applicable tuner.

This should result in the strongest signal with little interference from the other antenna. Of course it is also the solution that required the most amount of work.

[Fuzzy]

Originally Posted by sic0048

Well I think the best solution is to run both antennas completely separately. IE they each have their own coaxial run down to the tuners and each antenna gets plug into its own tuner. Then add only the channels that come in strong on each applicable tuner.

This should result in the strongest signal with little interference from the other antenna. Of course it is also the solution that required the most amount of work.

And the greatest change of conflicts...

[sic0048]

That's what they make HDHRs for

[GKusnick]

Remember this is digital TV we're talking about. Unlike analog TV, the signal doesn't have to be as pristine as you can possibly make it. It just has to be good enough to recover the bits without errors. Beyond that point, spending more to keep signals separate buys you nothing in terms of picture quality. So if you can get satisfactory results by passively mixing signals up on the roof, then that's clearly the most cost-effective way to maximize recording flexibility and minimize conflicts.