[Procyan]

I've been reading over this website for about a week now and the amount of knowledge here is impressive. I'm in upstate NY about 40 miles from Canada and this weekend I will be building my first antenna. I've decided to build a M4 bow tie because that one seems to be relativity easy compared with the SBGH also I have the parts on hand. If I get some decent results I will try my hand at making another antenna.

After checking out my TVFool results I'm not sure what a realistic goal would be for one of these antennas.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=da32186fb8ed1f

To me it looks like I will be needing alot of skill and perhaps some luck on getting most of the channels listed.
Please chime in with what setup you think would be the most beneficial. Thanks in advance

 

[majortom]

Hi,
First thing I noticed is that most, even the closest are listed as 2 edge.
Must be some rough terrain around there? If that's the case, is there
a reason that you plugged in an antenna height of only 10 feet?
Can you run it again several times at say 10 ft, 20 ft, and 30 ft, maybe even higher? Keep raising the height to compare predictions.
Post your results and lets see at what height you start seeing some improvement at the higher receive antenna heights.
That will give you an idea what your limitations are.
May just be the terrain like I said, but let's see. Also, if the terrain
is rough it will be critical for accuracy to plug in the exact address.
Regardless, the highest height you can get practically in your situation would work best in reality.

For what it's worth, I know someone who does well from Utica with his homemade SBGH + pre-amp on his rooftop.
His goal was to get the Syracuse stations without resorting to cable or satellite (especially for SU Basketball, etc).
is there something in particular on your wish list??

 

[Dave Loudin]

The easiest way to investigate different antenna heights in TVFool is to use the "start MAPS" option. The Google map that you get will have a red pointer that should be on your location. Zoom in as necessary and drag the pointer to exactly the right place. Next, enter different values for antenna height in the box below the map. Everytime you click away, the predictions will update. When you get a result you're happy with, click the radar plot button and share that with us.

majortom, click on any of the stations in his list to see a path profile. Transmitter on the left end, receive point on the right end.

 

[Procyan]

MajorTom,

There is no particular reason I put 10 feet in there just my inexperience. hehe I have a small tripod antenna that’s about 10 feet tall and my first idea is to mount that on to the apex of my roof and that should give me a total of about 30 feet. According to TV Fool that get me to LOS with a total of 2 broadcast antennas. It looks like I'm on the back side of a small hill, I was hoping to try to get some stations out of Syracuse. Here is theTVFool with my exact LAT and LON on a 30' antenna.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id=da32371fc661c7

Also the classification I know LOS is line of sight but I do not know what Edge1, Edge2 or Tropo mean. I worked military comms for 4 years with a Tropo shelter but that was with HF. Is the website talking about the same thing?

Thanks,
Procyan

 

[mclapp]

You have a shot at the Syracuse stations but everything would have to be just right and that's assuming your TVFool report is accurate. I've had success with reliably receiving signals that weak here in the southern tier of NY with an M4 but it requires a reflector and usually a decent quality pre-amp.

I'm not sure if you are using a reflector on your M4 or not but that will give you a boost of 2-4 db over no reflector. With the strong stations to the east of you an amp may be tricky but the side rejection of the M4 should help there. To help further you may try the curved or angled reflector and swept forward whiskers to further narrow the beam and squeeze a bit more gain. I have a drawing of the reflector dimensions here along with some other stuff.

 

[Dave Loudin]

Also the classification I know LOS is line of sight but I do not know what Edge1, Edge2 or Tropo mean. I worked military comms for 4 years with a Tropo shelter but that was with HF. Is the website talking about the same thing?

Edge-n tells you how many times the signal has had to scatter over terrain. Tropo is the same mode you were dealing with for HF comms. Click on any of the stations in the table of your TVFool report to see a path profile. The tropo paths are waaaay beyond the radio horizon.

 

[majortom]

Thanks for the tips Dave.
Doing as suggested (of course i don't know the exact location of the rcv antenna), but it looks like he starts to see Positive Noise Margins from the Syracuse stations at about 60'.

Procyan,
Don't let that discourage you though, as Mclapp says, a good quality Pre-Amp
May pull some out of the dirt for you. I would definitely consider one, they are a relatively cheap experiment (~$30-$40)
You can read thru the Pre-Amp FAQ here at DHC.
And there is a Cascaded Noise Figure calc Sheet I threw together a while ago, for my setup here in Buffalo that u can grab from Google Docs.
Just customise it for your own various proposed configuration scenarios.


here's ur radar plot at 60 feet, to compare with the one u ran from 30 feet.

 

[300ohm]

Tropo means that in order to receive that station, the signal has to bounce off the troposphere.
You can get a forecast of that happening here : http://www.dxinfocentre.com/tropo.html

It doesnt occur as frequently in the North as it does in the South, so its going to be fairly rare for you.

 

[Procyan]

Thanks for all the input guys. I ended up building a stealth Hawk antenna just to test my construction skills and to see if I could build something that worked. I first built a simple jig to bend the wires the correct degrees but one side is about 1/4in longer than the other side. I put the antenna in the exact same spot which is less than ideal and picked up 6 more channels after a rescan. Today I'm going to put mount it on the old dish network mast and that will hold us over until I get an M4 or a SBGH built. I got some pics I will post of the finished antenna and the mount position in a little bit.

mclapp:
You have some really nice kits for the M4 I'm really considering buying one of your kits. They are higher quality than I could possibility build out of my garage with the current tools I have. I'll see how my first attempt goes and if it doesn't work out I'll probably purchase one of your kits.

300ohm:
I worked in a HF tropo van in Germany and I had a lot of fun doing that. One of my first times in the van we put a link in from Germany to Italy. After we had the link established my team chief was teaching me some things on the shelter and flipped the switch to HI tropo, but we only had a 5k generator hooked up and the shelter almost instantly stalled the generator because it pulled so much power.

Thanks for everything guys I will keep you posted.

 

[Procyan]

Installation pictures.

If the last picture works, you can see I added a narod to it. The narod is 29" and according to the instructions the legs should have been 29" also. The feet didn't end up being 29" but I didn't want to cut off the extra on the narod so just put it up anyways. At first every thing was fine but at about 6pm I lost channel 7. I hooked up my old rabbit ears and 7 cam back. So just on a hunch I took of the narod and 7 came back in clear. I had the narod 1 inch away from the bottom of the legs. How far should I have it and what should I do about the length problem?

 

[300ohm]

NARODs dont really work with the Stealth Hawk antenna. They are for the Grey-Hovermann models.

Nice job BTW. But drill some holes in the bottom of the electrical box to let any water that does get in to drain.

 

[ota_canuck]

The multidirectional capability of that Stealth Hawk antenna may be the best choice given your scattered 360° broadcast market. Using a directional antenna will require the use of a rotor to aim toward the various broadcast towers.

If you feel like experimenting with the narod again, it should be mounted within 1/2" below the lower legs of the main elements.

You should find much improvement to signal strengths if you add some form of amplification to that stealth hawk.

 

[majortom]

no question, nice job.

I put the antenna in the exact same spot which is less than ideal and picked up 6 more channels after a rescan.

Can u summarize ur results?
Just curious, in terms of how far down the tvfool list your receiving now??

 

[Procyan]

Crap man I had just written a novel and got logged out and now its gone grrr!

Recap: last night I was receiving 7 digital channels and 3 analog. The digital channels were from WPBS, WWNY and WWTI. When I got home from work I wasn't receiving anything from WWTI, I checked the connections and everything seemed to be fine so I did a re-scan and the tv dropped WWTI from the channel list. So I'm not sure what to do now.

ota canuck:
I will try the narod again and this time I will space it correctly at 1/2in. What should I do about the extra length of the narod? I read in another post that I shouldn't trim it down. If I leave it at 29" and center it like I had in the pictures I posted will that me sufficient? I'm also working on a new jig that will make some nice sharp corners at any degree I want. So I might just bend a new element when the new jig is finished.

majortom:
When I was talking about a "less than ideal" position I had just got done with the antenna and set it on top of the tv cabinet and re-tuned the tv and got 6 more channels. The next day I mounted it outside on the old dish mast. Currently its on a 3 foot piece of 3/4 PVC pipe and that gives it a total of maybe 15 feet off the ground. I want to make it higher but the roof is covered in snow so this will be a spring project. I do have a 15 foot tripod mast that I will mount on the apex of the roof so that should really help. I’ll post a picture of the current and future location soon.

 

[mclapp]

That's about what I would expect, the stealth hawk has a broad beam but not much gain you will have almost no shot a Syracuse or anything else other than what you have now.

By the TVFool plot, the stations you are currently getting and the one you aren't should be quite easy to receive with most anything if pointed in the right direction. A full G-H isn't much harder to build than the antenna you have now maybe give that a shot.

If your out-lying stations were stronger I would say to maybe stick with the stealth hawk but they are all quite weak and the only real advantage of the stealth hawk is the wider beam which you really can't take full advantage of because the antenna can't pick those stations up reliably anyway.

 

[Procyan]

While talking with a friend at work today, I mentioned that I lost WWTI signal and he said he did also. Tonight I decided to look up the channel and it says this on the website.

"Due to the a National Grid fiber optic line being cut yesterday, we are currently off air."

so I guess its not my antenna. Also today I splurged and purchased a CM7777 titan 2 pre amp and it should be here right after Christmas. Ohh I'm so excited!

 

[ota_canuck]

I think you're going to see some signal improvement with the cm7777 preamp added to the Stealth Hawk antenna. The Stealth Hawk design has very little wind loading. Can you add some height to that mast?

[another issue to note: you are using a plastic mast that will not provide for grounding]
__________________________________

As I mentioned before, the other antennas designs may have a little more gain, but with that higher forward gain, those antenna are designed to operate very directionally and would require a rotor to aim the antenna at the many broadcast towers.
__________________________________

The Stealth Hawk is not truly omnidirectional. It is multidirectional which means it has several lobes and nulls over the 360° coverage area. Some fine tuning with the aiming may be required to tune into the sweet spots for your multiple broadcast tower locations.

Here's a link that may help you with aiming the Stealth Hawk antenna:
http://www.digitalhome.ca/forum/showpost.php?p=1148335&postcount=286

 

[mclapp]

As I mentioned before, the other antennas designs may have a little more gain, but with that higher forward gain, those antenna are designed to operate very directionally and would require a rotor to aim the antenna at the many broadcast towers.

Whats the difference in gain of a 30 degree beamwidth, bi-directional reflectorless G-H or 4 bay bowtie as compared to a sometimes bi-directional, sometimes multi directional stealth hawk?

It appears the stealth hawk may have more gain upwards than outwards.

Don't get me wrong I think the shealth hawk is a great antenna for it's purpose but the OP was hoping to have a shot at the Syracuse stations at 187 degrees in the -nm range on the TVFool plot.

Do you think that the stealth hawk with the cm7777 amp will do that?

 

[ota_canuck]

Theoretical antenna gain value and tvfool data are not the only factors to consider. Location, terrain, etc contribute to reception. According to tvfool data and nec gain calculations, the Stealth Hawk antenna should not work well in my area as well as a GH or a 4221, yet the Stealth Hawk outperforms a GH or a 4221 from my location. From my location I get WFXP 66.1 [22RF] from Erie PA. at 66 miles and a tvfool nm -6

In this case he is looking to acheive not only Syracuse, but 360° coverage of other scattered broadcast sources. Any of the directional antennas from his location, will need a rotor. Yes,.. Syracuse could be possible with a Stealth Hawk antenna if other conditions surrounding his location are favourable and he would not need to use a rotor.

 

[mclapp]

Theoretical antenna gain value and tvfool data are not the only factors to consider. Location, terrain, etc contribute to reception. According to tvfool data and nec gain calculations, the Stealth Hawk antenna should not work well in my area as well as a GH or a 4221, yet the Stealth Hawk outperforms a GH or a 4221 from my location. From my location I get WFXP 66.1 [22RF] from Erie PA. at 66 miles and a tvfool nm -6

In your location is the key to that statement. I think the G-H, bowtie style and stealth hawk antennas are past the theoretical stage as far as gain and reception patterns are concerned. No doubt that location and local obstructions have a great deal of impact on reception. We need something we could mix with the radio signals to see how they are flowing through the air.

In this case he is looking to acheive not only Syracuse, but 360° coverage of other scattered broadcast sources. Any of the directional antennas from his location, will need a rotor. Yes,.. Syracuse could be possible with a Stealth Hawk antenna if other conditions surrounding his location are favourable and he would not need to use a rotor.

I don't know for sure what the priorities are, I don't remember 360 deg reception being a priority but I do remember Syracuse reception being a possible goal. The more directional antennas may not need to be rotated to get all he wants it depends on what he wants. Remember even more directional antennas have some reception in all directions just greatly reduced in certain spots. It really depends on signal strengths in the area and the OP's priorities.

If he gets all he wants with the stealth hawk that's great a simple, inexpensive, and small antenna.
I was just submitting my suggestions for what I thought were his best DIY options to get the distant stations and what his chances were.