AVS Forum banner
1 - 15 of 15 Posts

·
Registered
Joined
·
40 Posts
Discussion Starter · #1 ·
I would like to combine three fixed antennas and send them to one TV/recorder.


These are the stations that I would like to receive;

Antenna 1 RF CH 9 & 32 pointed SSE

Antenna 2 RF CH 28 pointed NNW

Antenna 3 RF CH 45, 7, 43, 44, 14 pointed SW


I would prefer not to use a rotor and one antenna because sometimes I would like to record different shows from stations that are in different directions when I am not home. For instance lets say I want to record CH 9 at 10PM and CH 28 at 11PM but I am not available to rotate the antenna.


Is there any way to do this?


Thanks

Zack S
 

·
Banned
Joined
·
2,443 Posts
Need a TVfool report of your reception area. If the signals are strong it might work. Or you could end up with multi-path issues. Just doing a general plot for Royal Oak, MI RF 9 seems to be analog. Also 9 and 7 are hi-VHF the rest are UHF so it depends on which antennas you plan on using to see if your set up can work.
 

·
Registered
Joined
·
458 Posts
What models are the antennas? Ganging feedlines from different antenna types can provide some unexpected results. Your signals are strong enough that you also might be able to get away with just a simple omni-directional indoor antenna.
 

·
Registered
Joined
·
192 Posts
Do you have these three antennas now, or would you be purchasing from scratch? If you're purchasing new, you can probably get away with two antennas, if your main one has relatively low gain and relatively wide beamwidth. Perhaps a Winegard HD7694P pointed about due south (you'd have to experiment a little with the aim) would receive everything except 28. To add 28 to the mix, you'd use a separate medium-gain UHF-only antenna of any kind, joined to the main antenna using a 0585-1 jointenna tuned to channel 28 (which currently takes a while to get, unfortunately).

http://www.solidsignal.com/pview.asp?p=HD7694P
http://www.solidsignal.com/pview.asp...&p=OBO-HD-4400 (an inexpensive channel 28 antenna)
http://www.warrenelectronics.com/Ant...Jointennas.htm
 

·
Registered
Joined
·
192 Posts
Zack:


Combining multiple antennas aimed in different directions tends to introduce multipath distortion/interference into the equation for all stations received. If the distortion is not too severe, your tv tuner will be able to sort out and decode any given digital signal effectively. But if the distortion is too significant, you will experience dramatic signal strength fluctuations and intermittent pixelation and dropouts. To address this, special signal combiners like the Jointennas were created, which filter out a single channel or a group of channels from the non-intended antenna, passing the signal from that channel (or group of channels) from only the intended antenna. Since such filters usually are specialized separately for VHF or UHF frequency bands and focus on only one channel (or group of channels within only one of those bands), the intended antenna for the inserted channel is preferably a VHF-only or UHF-only model.


Your 2016 selection would probably be fine for your main (southwest) antenna. If outside, and aimed around due south, it might also receive 9 and 32 since they are fairly strong. The 3016 antenna you proposed for 9 and 32 would probably receive those stations just fine, but its 80"+ width means that it includes the wider horizontal elements necessary for receiving VHF- low stations (channels 2-6) that you don't need. So, you'd be using a much wider antenna than necessary, instead of one around 35" max width that is limited to VHF- high (channels 7-13). The proposed 4400 UHF antenna would also probably work fine for 28, just more expensive than the open-box one I mentioned, with roughly same performance.


Ideally, separate VHF-high-only and two separate UHF-only antennas for the three inserted channels 9, 28 and 32 would be used with three jointennas, but the 0585-2 model needed for channel 32 is supposedly permanently discontinued, so you'll have to do the best you can otherwise. Maybe starting out with your 2016 first and testing it would be the way to go.
 

·
Registered
Joined
·
1,570 Posts
Zaax,


Unless there is some especially compelling reason to want Central Michigan's PBS station in addition to WTVS, I would forget about channel 28. That leaves just the main Detroit stations in Southfield and a couple stations in Canada to contend with. I suspect that the local CBC affiliate, channel 9, is the main draw amongst the Canadian broadcasters in the Detroit suburbs.


My recommendation would be to get a moderately powerful VHF-Hi / UHF antenna and split the difference between Southfield and Ontario. Most of the main Detroit stations are within five miles; WKBD is 8.2 miles away and 65° off axis from the other Detroit stations. (I used to live a little north of you in Clawson. This meant that the Southfield stations were grouped more tightly together for me.)


CBET-DT is only 33° off axis from the main Southfield stations, but it is 22 miles further away than your local Detroit stations. I would try something like a single Winegard HD7694P which should work just fine. The beam width is nice and wide at channels 9 and 14 which are the farthest point off of your intended aimpoint. Alternatively you could get a VHF hi band antenna for CBET (and aimed back a bit toward the south to get WJBK) and then a UHF antenna for the rest of the American stations. In any event, best of luck and happy viewing!
 

·
Registered
Joined
·
5,414 Posts
I wonder if "Brian" charges mileage?



At first, I thought they were going to link to something like the Johannson Programmable Filters....Guess not.

That would be an elaborate, but expensive, way to do it. Not sure how much for their newer, mast mount models, but the U.S. version of the Profiler is around $1K.


How about using a couple of those Radio Shack (maybe others make them, too) IR-controlled A/B switches? If you are only doing one TV set/recorder input, maybe a programmable remote with built-in timer, would work. It would switch the antenna input at a preset time (as long as the remote is aimed toward the switch).


Might take some fooling around with, to make it work, or maybe there's a 3-input (A/B/C) switch version of it somewhere.
 

·
Registered
Joined
·
5,414 Posts
Just thinking a bit more...even if you needed two of the switches cascaded (making, essentially, an A/B/C switch), if your recorder has an IR Blaster output (that can be programmed to run one of the switches at the proper time), you could use that emitter to feed one switch, with it taped up to not see IR control from the programmable remote, and let the remote controller switch the other A/B switch.

It would take setting your schedule twice (once in the RC, once in the recorder), but might work.
 

·
Registered
Joined
·
184 Posts
As I read the TVFool report and your needs, it made me think what I might be up against. I might be buying a house in your neighborhood next year! However, in thinking about the area, I would probably go with simplicity and pick up a medium sized full band antenna and a rotor. You could get a shot at the Toledo locals. Based on the repeats of programming between WCMZ and WTVS, there isn't enough of a compelling reason to erect an antenna for one station IMHO.
 

·
Registered
Joined
·
5,414 Posts
That just reminded me....

The place we used one of those A/B switches was in a trailer we built for showing off Digital TV. And, we used a remote controlled rotor, too.

So, maybe the TV could control a rotor directly?

It was a Channel Master CM 9521A, and it allows for preset positions.

 
1 - 15 of 15 Posts
Top