Two Off Air Antenna's??

ProStreet · 11-12-2006, 04:38 PM

I have a HR 10-250 with a Terk Off-Air HDTV Antenna Model: HDTV-S that does a great job getting my Milwaukee channels. Now I live the same distance from Chicago as I do from Milwaukee and would like to get both. Being 50 some miles from both I feel I need a directional antenna. Short of using a rotor, how would I do this with a directional antenna? I would like to get another Terk Off-Air HDTV-s and have it pointing South and the current one pointing North. My question is if I can use two antennas, how would I hook them up to the one input on the HR 10-250?

willardcpa · 11-12-2006, 04:47 PM

Keep searching here. There have been other threads where folks have linked to "filters" that hook up to each of the two antennas and only let signals through for certain channels or ranges of channels.

A J Ricaud · 11-12-2006, 05:43 PM

Quote:

Originally Posted by willardcpa

Keep searching here. There have been other threads where folks have linked to "filters" that hook up to each of the two antennas and only let signals through for certain channels or ranges of channels.

Do a Google search for jointenna.

DavidTigerFan · 11-12-2006, 07:03 PM

get two antennas, point one towards Milwaukee, one towards Chicago, now run the lines into a normal cable splitter, now run a coax cable from the splitter to the Sat box. Boom, two antennas.

pinballfan · 11-12-2006, 07:18 PM

Quote:

Originally Posted by DavidTigerFan

get two antennas, point one towards Milwaukee, one towards Chicago, now run the lines into a normal cable splitter, now run a coax cable from the splitter to the Sat box. Boom, two antennas.

I'd suggest using mast mounted amps on each antenna to help overcome the signal loss introduced by the combined cables. Otherwise I agree.

FWIW, I do this to pick up both NH (north) and MA (south) stations...

JimSpence · 11-12-2006, 07:46 PM

DavidTigerFan's suggestion is good for a start. However, if either antenna receives signals meant for the other one, you'll get interference which may block the receiver from locking on to the station. There is a problem with multipath and this joining of antennas could cause it big time. Otherwise do the search for "jointenna".

mr.unnatural · 11-12-2006, 10:40 PM

If all of your HD OTA channels are in the UHF band, all you need are two directional antennas pointed in opposite directions. I'm in the exact same situation as you as I'm located directly between Baltimore and DC. I have two Channel Master 4228 8-bay bowtie antennas pointed at each set of broadcast towers. The two antennas are combined using a standard splitter/combiner that covers the UHF frequency band. I would avoid using an amplifier if you don't need one as they tend to amplfy the noise as well as the signal. The 4228's should work for you as they are meant for long distance reception.

Unless you have duplicate channels in both markets (i.e. two channels on the same UHF frequency) you shouldn't have to worry about interference. UHF antennas are highly directional and it is unlikely that the one pointed in the opposite direction will pick up a signal meant for the other antenna. OTOH, there is always the possibility of reflections causing multipath interference but it shouldn't be a problem unless you are living in an area with lots of tall buildings or other high structures.

I would recommend simply setting up two antennas like I suggested and then see if you have any issues with interference. I'm not sure what you could do about it unless you could insert notch filters to eliminate the multipath interference.

borgslayer · 11-13-2006, 08:32 AM

I live between Ft. Lauderdale and W.Palm Bch. In my scanning of OTA channels there is a secondary market choice, wouldn't this work the same as the having two Antennas as the OP wants?
Scott

Raj · 11-13-2006, 08:40 AM

I agree with the suggestion that you should just get two directional antennas and point them in the required directions.

To combine them, use one of the coax splitters. A splitter can be used as a joiner.

For analog TV in fringe areas, some people used single channel (yagi) antennas that they combined using a combiner.

If you're getting multipath from a strong station you may need to use a notch filter but in most cases it is not necessary.

What I think that TV manufacturers should reintroduce is the TV that controls an antenna rotator like the old heathkit one did. Change the channel and the antenna points in the correct direction. But I'm not seeing it happening since they're making TV's cheaper and cheaper and assuming that people are using satellite or cable.

mr.unnatural · 11-13-2006, 08:41 AM

Quote:

I live between Ft. Lauderdale and W.Palm Bch. In my scanning of OTA channels there is a secondary market choice, wouldn't this work the same as the having two Antennas as the OP wants?

No. You can set up a secondary market via the menus to receive guide data from a city other than the primary market determined by your zip code. You'd still need an antenna to pick up the channels. If the broadcast towers are located in different directions you'd need two separate antennas aimed at them. Good quality UHF antennas tend to be highly directional and can only detect signals within a narrow reception beam. Omnidirectional antennas are available but they're usually short range and poorly designed, resulting in excess noise and multipath interference. Many designs contain built-in amplifiers but all that succeeds in doing is amplifying the noise floor.

TiMo Tim · 11-13-2006, 01:29 PM

Note on 2-antenna hookups using just a splitter/combiner: be sure that both cable runs are the same length (before the combiner). Mine weren't at first, and it worked fine (I knew the problem existed, but since mine worked, I didn't bother heeding that advice). But then something happened, and I lost one of the stations-- its signal quality jumped around wildly on my HD-TiVo. Created two new cables of identical length, and voila! Problem solved.

mr.unnatural · 11-13-2006, 01:53 PM

That sounds more of an issue with the cable itself or possibly a bad crimp connection. As long as the difference in the two lengths is not extreme (i.e. one 10-ft and the other 50-ft or more) then the difference would be negligible. Still, having them of equal length is not a bad suggestion.

louiss3000 · 11-13-2006, 02:26 PM

This seems like a good time to ask this: I too live between Fort Lauderdale and West Palm Beach. All the FTL and Miami HD OTA locals are fine (except for FOX). My question is on a WPB channel, NBC5. I have lots of signal as shown on the HR10-250, my TV gets it fine, but the HR10-250 shows it as "Searching for signal" on off-air anrenna. I thought it might be the secondary market choice, but no joy. It is listed in the guide data correctly, just can't watch it.

Any ideas appreciated...

ProStreet · 11-13-2006, 03:59 PM

With having UHF and VHF from both Milwaukee and Chicago would the jointenna block some channels? What model would I need to get all the stations? None of the stations share the same frequency. Im kind of lost now, other than trying the splitter option.

TyroneShoes · 11-13-2006, 08:27 PM

Quote:

Originally Posted by JimSpence

DavidTigerFan's suggestion is good for a start. However, if either antenna receives signals meant for the other one, you'll get interference which may block the receiver from locking on to the station. There is a problem with multipath and this joining of antennas could cause it big time. Otherwise do the search for "jointenna".

I agree. Connecting two antennae to the same splitter (combiner) is effectively taking two directional antennae and turning it into one system that is much less directional, which is counter to what HD reception requires in most cases.

But it can still work, although if it does, count that up to sheer dumb luck. But it is still worth a try, and not trying it might be even dumber.

There are some ways to increase your odds of success, tho. The first is to take a hard look at the channels out there and the directions they are coming from. If your two directions are somewhat opposite of each other, sometimes a yagi with poor front-to-back ratio is just the ticket. Point the back end at the stronger stations and the weaker stations should come in OK. If not, point the front end at the weaker stations and see if the stronger stations still come if off-axis on the backside.

If your azimuths are 40-120 degrees apart, that trick won't work, and two antennae are required. Look at your stations available. Very likely, only 5 or 6 of them will really have anything in HD that you want, so disregard the others and concentrate on the big 5 and PBS. Now, determine if those from one direction are all UHF or all VHF. If so, simply use a cut V and a cut U antenna, and a U/V combiner. If one direction is U only and another is both U/V, use a cut U and a U/V, and combine with a normal splitter. If that doesn't do it, you may need a jointenna filter, but that will only work if the frequencies are just right. Whatever you combine, using antennae with the highest directionality will work the best.