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Discussion Starter · #1 ·
I know all about antennaweb.org and know my external OTA antenna needs to be pointing to 148 degrees.


Not sure how exactly to shoot that angle. What I'd LIKE is some little meter gizmo I could plug into the coax coming from the antenna and wiggle the antenna back and forth until the signal strength is as max as it's going to get. They've got these for DirecTV satellite dishes, why not UHF?


Anybody know of one? Or an alternative to get my antenna pointing in the right direction? Trying to look at the signal strength on my screen (I use an HTPC with an HDTV card) is a pain because I'm all the way at the other end of the house from it on the second story, plus the signal strength meter isn't very responsive - there can be a wait between instantaneous and 45 seconds before a slight change to the alignment of the antenna makes a response, and changing channels to verify they're ALL better isn't the fastest process in the world either...


--KS
 

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AFIAK, there are no "affordable" handheld devices that will do this. There are digital spectrum analyzers but they run into the $thousands$. The best solution for me was to buy a pair of wireless headphones and use the audio feedback "beeps" from my receiver to zero in. Granted, this may not work too well with your PC card.
 

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With terrestial broadcasts, the strongest signal isn't necessarily the best signal due to multipath, so a simple meter will often mislead you (satellite dishes are highly directional and line of sight to the source so mulitpath isn't an issue).
 

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One way is to find a map that has compass bearings on it or since maps normally point north use a protractor on your local map. Then draw a line from your location to 148 degrees. Then look for a landmark or street crossing on the map that you can see from your house that is on the line and point your antenna at that landmark or street crossing.
 

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Why not just get a compass with the bearing numbers already on it.


Find true North(which I believe is 0 degrees).


Slowly turn towards the east until you reach 148 degrees(it does not have to be dead on either. Between 145-155 degrees should suffice) Antenna's DON'T need to be exact.


This is not hard to do, and this type of compass is not hard to find. Try WalMart, Dick's Sproting Goods, Target, or any sporting goods/hunting shop. They should have compasses available. Even digital ones which tend to be a little more idiot proof.
 

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Quote:
Originally Posted by STEELERSRULE
Why not just get a compass with the bearing numbers already on it.


Find true North(which I believe is 0 degrees).


Slowly turn towards the east until you reach 148 degrees(it does not have to be dead on either. Between 145-155 degrees should suffice) Antenna's DON'T need to be exact.
Magnetic north and true north can be off by several degrees, I believe where I live there is currently about 6 degrees separation. I seem to recall that somewhere on the antennaweb site it tells the directions it gives are for magnetic compasses.
 

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What I do is tune my UHF/VHF antenna using aa analog station. It's much easier to determine how much multipath you're getting with analog than digital. The signal strength meters on most devices are pretty useless.


This, of course, requires the antennas for the HD stations to be in the same location as the SD stations.
 

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Get a two phones (one cell/portable?). Bring up the S/S meter on the TV. Have someone looking at the meter on the TV.


Have someone on the second phone at the antenna. Position the antenna for the best results and relay the info using the telephones.
 

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Quote:
Originally Posted by Ratman
Get a two phones (one cell/portable?). Bring up the S/S meter on the TV. Have someone looking at the meter on the TV.
If your and antenna has an amplifier, will it be overloaded by operating a cordless phone or cell phone next to it? Have a party and play post office.
 

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What is your issue(s)?


My suggestion is feasible and it works well.
 

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What antenna are you using first of all? Is it a highly directional yagi or 8 bay? If not, then exact orientation may not be neccessary. Unless you are on a fringe reception area and getting marginal reception, a few degrees will not make much difference.


I was able to get my CM4228 aligned good enough to get all of my local digital stations at 85% or better by simply guessing the direction based on arial photos and the map that Antennaweb gave. I'm 20 miles from the towers and the spread of different towers is like 10 degrees. I had to shoot for the middle. After the first try, I only had to make a slight adjustment once to optomize my Fox station, but that's it. Luckily my house is aligned almost perfectly north/south.
 

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Quote:
Originally Posted by Rack
http://www.emitor.se/websites/emitor...in.asp?ID=3541

There you go.

Then again, vman seems to be right. I don't think this instrument is looking for quality, just strength. On some channels (like the weak ones), more strength should help. But on others (like the close/strong ones), a cleaner yet weaker signal might yield the best results.
And how does this do anything different than the meter built into digital tuners?


Sheesh... a phone call and a compass is less expensive.
 

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Discussion Starter · #14 ·
Wow, lots of responses!


- First, my antenna - I have a plain old Radio Shack 40" Boom 17 element UHF directional.


- Second, my location - I live out in the boonies (on 24 acres about 46 miles from Houston, TX where the transmitters are - and for those of you not in the know, Houston is exceedingly flat - no hillly terrain between me and the city or anything), and that means very luckily ALL the stations I want to receive are aligned on the 147-148° line according to antennaweb.org


- Third, my antenna is mounted at the peak of my 2nd story roof. There are no nearby trees or structures nearby as I have a completely cleared path to the fenceline roughly 1300 feet away in about a 60° wedge centered on the 147-148° line, so multipath probably isn't an issue for me.


My house is aligned North/South, but not perfectly. When I first set up my HDTV, I used an indoor set top antenna which worked surprisingly well, but quickly upgraded to this outdoor one with a powered signal booster on it. I get a couple stations VERY strong - no dropouts - and the rest of the 7 or so fair-to-middling. With the indoor antenna, I got them all equally well (quite by accident when I found the "perfect" alignment - which my stupid cat managed to munge up for me 5 weeks later and I never found again). When I set up the outdoor antenna, I just "guessed" where 147-148 was. I'm finally sufficiently "grrr'd" about it to try to do something a little better.


The "talk to somebody with a cellphone/FRS radio" idea - doesn't work because of the lag on the software signal strength meter on my HDTV card. I'd "ootch" the antenna one way, and then have to wait 2-3 minutes for a "Um...I think it's about the same" message...


Normally, I'd have already tried the compass idea. Except I tried that before and had a few issues - I have a metal frame house and it makes compasses (even when on the roof) act a bit wonky. I'll try it again though - I just need to figure out the degree offset from mag north, which means I'm going to have to figure out my lat/long; be nice if I had a GPS.


--KS
 

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Quote:
Originally Posted by KlingonScum
The "talk to somebody with a cellphone/FRS radio" idea - doesn't work because of the lag on the software signal strength meter on my HDTV card. I'd "ootch" the antenna one way, and then have to wait 2-3 minutes for a "Um...I think it's about the same" message...

--KS
This is exactly why I say use an analog channel. Given the situation you describe I think it's a safe bet your analog channels are in the same direction as your HD channels. Pick one of the weaker stations and tune it in the best you can. The person on the other end should be able to tell you when the picture is the best, unlike trying to go by the next to meaningless "signal strength" meters on most HD devices, most of which don't really measure signal strength.
 

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Quote:
Originally Posted by Ratman
And how does this do anything different than the meter built into digital tuners?.
I'm not familiar with that device, but it possibly measures signal strenght, which the meter built into most digital tuners does not.
 

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Due to your distance and terrain, you probably (nothing is ever certain with antennas) just want to maximize your signal strength. I'd try tuning in analog stations from the location for the first cut.
 

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UHF antennas are not so directional that they have to be pointed precisely at the transmitter. If you can determine the general direction to the transmitter, point the antenna that way and enjoy. If you are not satisfied with that, get a rotor.
 

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Quote:
Originally Posted by KlingonScum
Normally, I'd have already tried the compass idea. Except I tried that before and had a few issues - I have a metal frame house and it makes compasses (even when on the roof) act a bit wonky. I'll try it again though - I just need to figure out the degree offset from mag north, which means I'm going to have to figure out my lat/long; be nice if I had a GPS.
The government has an online Magnetic Declination Calculator that will tell you the deviation for your location and it also do it by zip code.
 

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All the suggestions here are usable. I used the cell phone with my wife inside and that works well. Use a compass heading corrected to true north (add magnetic variation to bearing to obtain compass reading, or go to 2150.com and it will calculate it for you). Use analogs in the same direction as a guide. If you're still having problems, it's likely you'll need to do something else other than tweak the antenna aim i.e. bigger, more directional antenna or a different location/height altogether.


Magnetic variation is usually a negative number east of the Mississippi, it's probably around zero in Texas or maybe +1-+2.
 
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