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57degrees
14-Feb-2010, 7:18 AM
First off, this site is great. Thank you!

My question is: can I connect two antennas together if they point in different directions?

Looking at the TV Signal Analysis Results (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d27eefe16f303c0), you can see that the stations in my area come are mostly grouped in three directions - north, east, and south.

When I bought the house, it came with a nice tall mast with two bow-tie antennas on it. I have hooked one of them to my TV (the one that points north). I do get several usable signals from the south, but from the east, the signal breaks up a lot.

Is there a way for me to connect the second bow-tie antenna to the TV (or the first antenna) so that the signals from the east are stronger?

I don't know much about antennas, and wonder if combining the two signals helps or hurts. I would expect that if both bow-ties pointed in the same direction, it would help. But I wonder if pointing them in different directions would cause the same sort of trouble that multiple paths cause.

Thanks!

57degrees
14-Feb-2010, 8:54 PM
After a little more research, it looks like what I am wanting is called antenna stacking. And it appears that a Winegard 3700 signal combiner (http://www.solidsignal.com/pview.asp?mc=03&p=SD-3700&d=Winegard-SD-3700-300-Ohm-TV-Antenna-Coupler-(SD3700)&c=Signal%20Combiners) is what I need.

Does that sound right?

Or am I going to need two Yagi antennas to pick up both the north signals and the east signals?

Thanks!

mtownsend
16-Feb-2010, 9:43 PM
Hello and welcome!

Combining multiple antennas causes the effective gain of each antenna to decrease. That is because gain and directionality are very closely related (high gain requires high directionality and low impedance mismatch). Combining antennas pointed in different directions makes the system less directional, and thus it will lower the effective gain you would expect out of either antenna by itself.

You are also correct that there is risk of opening up the doors for more multipath to get in. There's no way to tell if multipath will become a problem or not until you try it.



The good news is that your signals are very strong overall. You don't actually need much gain to get most of your channels.

To combine the two bowtie antennas all you need to do is use a 2-way splitter in reverse. This will lower the effective gain of each antenna (but you probably don't really need the gain), and it will increase your susceptibility to multipath. However, it's easy enough to try and see how things work out.

If multipath does become a problem, then it means that there are too many reflections hitting your location and you're better off not using both antennas at the same time. An A-B switch would be the next best option at that point.

57degrees
17-Feb-2010, 1:15 PM
You are correct that most of the stations come in fine. It is the one that is at ~90 degrees that is choppy and occasionally drops out.

Thank you for that explanation. It makes sense. Looks like I'll need to figure out a different way to get the Fox network. The house had previously been wired for cable TV, so I might just run the second antenna to a different room.