Stampeder, you are correct that multipath is a problem but no so far for me. It certainly is a problem with the NTSC channels using the same antennas. I guess my lack of multipath has a lot do with signal going through nothing more than plywood, shingles and a few roofing nails and the sophistication of the Samsung T451 tuner. I suspect that my finding will be true for many of us with "standard issue" houses.

Now, how about the rest of my brilliant rebuttal of outdoor antennas ;-)

I would have thought the group delay for a signal reflected inside a small space such as an attic would be very short and of lesser concern than the longer group delay caused by reflection from distant buildings and mountains.

Sorry if this has been discussed, but I searched and couldn't find it.

Part of my planning is figuring out which way to point my antenna. I figured if I got lucky I could go with a roof mount which wouldnt be visible from the front of my house.

One major question was: which way did I have to point the antenna. I wrestled with the math for a while and then I found this site:

http://www.movable-type.co.uk/scripts/LatLong.html

Using google earth, I wrote down the coordinates of my house in Milton to Toronto (43 38 51.27N 79 22 49.49W, and Buffalo (42 53 13.34N 78 52 48.57W) I copied the numbers into the above site and found that it is 54 KM and a bearing of 76 Degrees 04' 55" to Toronto and 117.58 km and 127 degree 10' 15" to Buffalo.

Armed with my compass, I should be able to site the antenna and, when necessary, align the antenna(s) to the above bearings.

I thought youse might find it useful.

That's a great starting point. With most ATSC tuners you should have a signal strength or signal quality meter that will let you take the final setup step of "peaking" your antenna for its specific best performance. Make sure to do that with all the expected channels in that direction so that you can come up with the best compromise among them. I've seen signal strength change with even just a tiny twist of the mast, so taking this step is definitely worth it.

One more thing: if you're using 2 or more antennas don't be surprised if your common logic about aiming goes awry as their reception lobes superimpose and interact. You might discover like some other DHCers have that some really weird effects happen, with resulting aiming that is counter-intuitive. It doesn't always turn out too radical, but ya never know... ;)

This site is very interesting and informative.

Building a MythTV Antenna System
by Matthew Gast
03/15/2006
http://digitalmedia.oreilly.com/pub/a/oreilly/digitalmedia/2006/03/15/antenna.html

Over-the-air reception with an antenna can be a maddening affair. TV signal strength can vary dramatically with small position changes, especially indoors. Depending on your location and willingness to get up on the roof, it may take a great deal of tinkering to get an antenna system set up right.

My own TV antenna system is the product of a great deal of fiddling. The motivation is the start of baseball season in March. Oakland A's games are broadcast on channel 36 in the Bay Area, but channel 36 is not broadcast from the area's main TV tower. To bring in the additional channel, I needed to find out where to point the antenna, join it in to my existing antenna, and ensure that a good enough signal was available throughout the whole system. It required extensive experimentation, and it took quite a long time because of a demanding travel schedule.

An easier method (though not as refined) is to use the Measure tool in Google Earth:

1. Draw a line between your antenna and the transmitter using the measure tool.
2. The line will pass through landmarks along the sight line to the transmitter.
3. Aim the antenna at a landmark you can see / recognize.

No compass, no measuring, no calculations :D

In my case I aimed my silver sensor at Grand Island, NY and I can pick up a couple of Buffalo stations as long as the weather's not too bad.

Here is a great tool to find the distance and relative direction of stations that should be available in your area.

http://www.2150.com/broadcast/default.asp

I have not seen this listed here yet.

Yep, videobruce has posted about that site a few times in the past, so if you know your geographic coordinates beforehand and you're able to tell which stations are actually alive from out of the results list that you get, you can get some terrific info on reception possibilities.

In my case I aimed my silver sensor at Grand Island, NY and I can pick up a couple of Buffalo stations as long as the weather's not too bad.If Grand Island is a landmark that you can see from Toronto then your eyesight must be REALLY GOOD.

I'm just letting everyone know that OTA TV Rotors now have their own thread in the OTA Equipment & Vendors sub-forum:

Rotors: Archer, Channel Master, Yaesu, Hy-Gain, Zenith, Others

http://www.digitalhomecanada.com/forum/showthread.php?t=41103

When mounting a CM 4221 to a 1 1/4" mast is it secure enough if you insert the centre pole (with the bowties) directly into the mast or would you recommend drilling a hole through the mast into the centre pole and putting a bolt or screw through ... or, is it better to just use the U bolts instead? I'm worried about it twisting in the wind.

Any advice would be appreciated, Thanks again.

...is it better to just use the U bolts instead?The standard clamps/bolts that (hopefully) came with your CM4221 are all you need. I've never seen them fail. :)

I'm sure that method would be the most durable but I would prefer to mount the centre pole directly into the 1 1/4" mast for the added height it would give (about 2' higher) but I'm just worried it wouldn't be strong enough in high winds. I just wondered if anyone else has mounted one that way and if so, how has it held up?

The link below shows a picture of the mounting method in question.

http://www.hdtvprimer.com/ANTENNAS/cm4221.html

Only $5 !!

http://cgi.*********/Antenna-Tower-TV-Television-Ham-Radio-25-feet-high_W0QQitemZ9718126350QQcategoryZ73383QQssPageNameZWDVWQQr dZ1QQcmdZViewItem

http://i3.ebayimg.com/04/i/06/fb/b7/37_3.JPG

http://i23.ebayimg.com/03/i/06/f5/ef/40_3.JPG

From auction : This unit is sold AS IS, WHERE IS.
The winner is responsible for taking down the tower.

I would rather just go and buy a new one if winner has to go and take down and move.

From auction : This unit is sold AS IS, WHERE IS.
The winner is responsible for taking down the tower.

I would rather just go and buy a new one if winner has to go and take down and move.

Yeah but a new towers going to cost you what? $300 to $400 ??

This ones only $26 with its current bid.

Wow the old tower sold for $128!

I use a combined 4221 (Toronto) and a 4228 (Buffalo).

I combined them with a standard antenna/cable splitter. Used backwards, a splitter is a combiner. The output of your combiner goes to the pre-amp input. There is one trick you need to know; there are wires on the 4228 that join the 2 rows of 4 bay antennas together. You need to compensate in cable length to get the 2 antennas in-phase. So, you need to make the cable on the 4221 about a foot longer than the cable on the 4228. You might end up with too much signal, on most tuners, overload will look like pixelation or freezeframe. But you can use an attenuator. The Source still has radioshack 6dB attenuators.

I've heard of other people combining them with 300 ohm antenna cable and using only one bal-un, but i haven't tried it to see if it makes a difference.

Hi!

This is probably a dumb question but how long can one expect a (antenna) tower to last?

I've got a (antenna) tower on the side of my house (I think it's 30 feet) which was installed there many many years ago (I'll have to inquire as to its age with somebody who should know...). and I was wondering if it could still be good...

It seems to still be pretty solid but it looks like there some corrosion at the bottom and possibly some rust at the top (can't really say as I'm afraid of height so I can't get a closer look).

There are two antennas at its top but they'll both have to be replaced if the tower it still good...

The main one, which is on a rotor, lost a lot of its parts during an iice storm and the preamp that was connected to it blew up when the tower/antenna was hit by lightning so it no longer works...

The second antenna still works but it's a lot smaller and is not on a rotor so the number of channels I can get with it is very limited...

Both antennas were, AFAIK, VHF/UHF/FM and were put there so that people could watch different channels AFAIK...

I'm only watching analog channels currently but I plan on purchasing a ATSC tuner eventually (I'm still not quite sure if I should get a STB or build an HTPC.. I've been reading most if not all of the stickies here and I'm still not decided... :D )....

Thanks!

Nick

As far as the results go, I've got the rotor on there but haven't actually used it. It's actually not powered up yet. It's aimed exactly at 170 degrees using magnetic North.
How do you calculate that direction?