[mythtv-users] HDTV antenna quandry

Mark fairlane at springcom.com
Wed Apr 25 11:01:01 UTC 2007


Rich Osman wrote:

>Mark napsal(a):
>
>  
>
>>Maybe one of you guys has run into this before...
>>
>>I'm planning on moving to HDHOMERUN boxes in the near future, but I have
>>a dilemma.  I have multiple stations nearby, Lansing 30 miles to the north,
>>Kalamazoo 45 miles west, and Detroit 60 miles East.  I need higher gain
>>antennas pointed in multiple directions.  I could do it with a rotor,
>>but then I might miss
>>a show on a channel where the antenna isn't pointed.  Best bet is
>>separate antennas.  Can antenna feeds for digital broadcasts be combined
>>with a splitter/combiner?
>>Or should I run each antenna feed to a separate hdhomerun and play with
>>channel/input  priorities until it works right? Currently this is my
>>only avenue for recording HD.
>>Cable and Sat don't carry what I want.
>>
>>Thoughts?Mark,
>>    
>>
>
>A plain old splitter rated for the highest channel (frequency) you  
>want to watch will do fine. The splitter will add loss, a two-way  
>splitter is half the signal level even when used as a combiner.
>
>You don't mention the channels involved, so it's hard for me to  
>provide very detailed advice. I'm assuming that you want multiple  
>channels from each direction. If not, 'single-channel' (really, a  
>small number of channels) antennas are far more efficient for their  
>size.
>
>If you mount multiple antennas on a single mast, make sure that you  
>space them far enough apart. A decent rule of thumb is half the width  
>of the widest element between antennas. This also applies to above  
>whatever you are mounting it to. I noticed another poster mentioned  
>cable lengths and such. That advice doesn't apply to your case. It's  
>for combining multiple antennas on the same signal, which is not what  
>I think you are asking.  I believe that you want to have an antenna  
>pointed at each city, right?
>
>In spite of the distance you may find that you get good signals off  
>the front or even the back of the antenna and make things work. I'd  
>start with one antenna and see what you can get. Watch an analog  
>station from the same city on a nearby channel. If you can get a good,  
>watchable picture on that it's likely that you'll have good margin on  
>HD.  This is a function of terrain a bazillion other things.
>
>Avoid amplification if you can. It can make things worse more easily  
>than better unless you really understand what you are doing. If you  
>need to add an amp, it's best to get it as close to the antenna as  
>practical. Use good cable and connectors. The thumb rule here is  
>'thicker is generally better' and use good connectors properly  
>applied. The new compression style F connectors can be bought in  
>weatherproof versions and tools to apply them can be had on eBay for  
>~$20. Make sure the connectors you get match the cable.
>
>  
>
I've already got a big corner reflector yagi on the roof now, and it has 
to be turned in the direction of the station I want to get anything.
Unfortunately, my tv cannot handle this operation and the channels must 
be re-scanned each time I turn the antenna to get the new station.
At a cost penalty of several minutes.  We're far enough away that 
smaller less directional antennas don't pick up anything at all, so 
unless I
can get a stacked single-run setup working, I'm probably not going to be 
able to pickup multiple directions at once...


More information about the mythtv-users mailing list