OTA at 70 miles?

[jcm.oo]

I know Jeff has told me before that 60 miles was about all you could get out of UHF. I know 70 miles would be pushing it but with the right stuff, good antenna and preamp could you pick up a signal? This isn't for me, my grandfather lives about 30 minutes south of me and I thought he may be able to pick up the Newport news channels. What do you all think?

[dave1234]

It would depend on the path to the signal. If there is a line of site directly to the TV towers then this may work. If the receiving antenna was at the base of a hill reception even 10 miles away may not be possible. UHF reception is very dependant on surface topology.
I would try a temporary setup to determine reception ability before investing much money.

[KyL416]

There are also several other factors besides the path, like the power of the signal. Try going to AntennaWeb.org and entering his location. It shows you what channels are available in the general area including surrounding markets, and reccomends what type of antenna you need to recieve those channels. It also has a street level map available with compass orientation so you know where to point the antenna to get the best signal for the channels.

Another nice tool that lets you select the individual channels is available at TitanTV.com, signup, create a profile for your grandfather's location and use the antenna selector tool in the DTV/HDTV tools section in the Command Center menu.

[jcm.oo]

There is no hills mountains or anything, very very flat land. About 18-20 miles of it would be over water. He has a 70 foot pole that he could mount this antenna on. They are showing on Antennaweb at 70-75 miles, but those are mostly all VHF. The digital stations are all UHF. When the analog to digital conversion is complete will most stations switch their digital channel back to their primary channel?

[KyL416]

Nope, most stations are planning on staying on their digital frequency.

[Jim5506]

I have heard of people along the Pacific Coast getting a steady DTV signal at over 100 miles over water with deep fringe equipment.

[olgeezer]

Outside antenna with rotor, shouldn't be a problem in your area as long as there arent building or terrain obstructions within about 3 blocks

[Jeff McClellan]

He needs good equipment if he wants a steady signal with no drop outs.

[jcm.oo]

What equipment do you recommend? I know the channel master 7775 is a good preamp but what about antenna?

[Jeff McClellan]

For that distance either a Channel Master 4228, Antennas Direct 91xg, or this
http://www.hdtvprimer.com/ANTENNAS/DAT75.html

[jcm.oo]

Is there a length for coax cable that will be just to much and really degrade the signal? I know the shorter the better, but I got thinking about the length of the cable. Going down a 75 foot pole, over the the house and back up again. Seems like that could cause a problem. I would be using RG6 as well.

[Jeff McClellan]

That is where the pre amp compensates for signal loss due to you long cable run.

[olgeezer]

You'll probably need a tower and rotor. If you have a hard time finding the stations, search in early morning before the sun comes up. And the last variables are the quality of the OTA tuner and the power of the station signal. Good luck the longest distance signal over land I've heard of and only in early morning was over 600 miles.

[jcm.oo]

The tuner is a dish 811. He may or may not do it, I will let you all know what the outcome is.

Thanks.

[Bill R]

Most stations are planning on staying on their digital frequency.

Not in my market. Most of the network stations (ABC, NBC, CBS and Fox) are going back to their currently assigned analog channels once analog is shut down. Three out of the four are in the VHF band. One PBS station also said the the are going back to their currently assigned (UHF) analog channel.

[Neil Derryberry]

Seems like we went through this before..

at 70 miles, OTA may as well be NoTA unless you have a degree in RF engineering, a large budget and a lot of time on your hands if you ask me.

[ericha]

You can't say "at 60 miles it works, at 70 miles it doesn't". There are just too many variables.
A person with a degree in RF engineering (actually this would be more Communications Engineering, which is a different sub-specialty) would build what's called a "Link Budget". It would look something like this:

(by the way, I have an EE degree, and I define RF & Microwave Test Equipment)

Transmit Power: X Watts (to be convenient, this would be converted into something like X1 dBm or maybe dBmV since TV people use those units)

Transmitter antenna gain: X2 dB

Free space loss at YYY MHz for 70 miles: X3 dB (you can look this up at: http://www.comsearch.com/satellite/tools_fsl.jsp)

Margin for multipath: X4 dB (the reality of this totally depends on where you are, where the transmitter is, and what's in between, and sometimes even nearby).

Receiver antenna gain: X5 dB

Receiver noise figure: X6 dB

Desired SNR: X7 dB.

Thermal noise: -174 dBm/Hz or -106 dBm for a 6 MHz channel; call this X8

The equation to solve is (if I remember correctly):
X1+X2-X3-X4+X5 - (X8+X6) >= X7

There may be another fudge factor in there because of the way that TV transmitters measure power (they use peak power instead of average, if I remember correctly).

The desired SNR for analog is 40 dB (or more). At 20 dB the "snow" is just about unliveable. For digital, the SNR numbers are somewhat lower, but the transmit power is a lot lower as well.

So to predict if this will work or not, you would need to know:
-The transmitter power (you can get this from the FCC web site, or call the chief engineer at the TV station)

-The transmitter antenna gain (this is probably harder to get, but it's probably at least 3 dB, and I'd guess might be as much as 10 dB in special cases

-The fudge factor to use for the terrain (X4). This is almost impossible to know. Theoretically, it's possible to calculate, but it is extremely complex. With a clear line of sight & no big reflectors nearby, it might be pretty small. But to get a clear line of site at 70 miles, probably the transmitter has to be on a mountain (farily common), and the receiver anteanna has to be on a mountain or a pretty high tower.

-The receiver antenna gain. You have a fair amount of control over this. A reasonable multi-channel antenna might have 0 to 3 dB gain. A Yagi tuned to the frequency of the station might have 10 dB gain. You can "stack" Yagi's to get more gain--I've seen pictures of 4 Yagis mounted (at the correct distance) on the same pole; I believe that gains above 15 dB or more are possible

-The receiver noise figure. If you use a preamp near the antenna, and the preamp gain is larger than the cable loss to the TV (or other receiver) plus the noise figure of the TV, you can pretty much use the noise figure of the preamp. Cheap preamps can have a noise figure of 10 dB or even more. Good ones, tuned to a single channel, will be a few dB. Very good ones (and very expensive ones) will have a noise figure measured in 10ths of a dB.

So because you don't know a lot of the terms in the equation, you can't really predict what you'll get. But let's see if there is any possibility:

Assume:
1) Transmitter power of 100 kW (pretty big, but possible for a UHF station). This is 80 dBm
2) Transmit antenna gain of 3 dB
3) Free space loss at 500 MHz for 70 miles is 128 dB (a pretty big number!)
4) Reciver antenna gain of 10 dB
5) Receiver noise figure of 3 dB
6) No fudge factor for multipath

In this case you get plenty of signal--the SNR is 68 dB. Now if the real transmit power is 20 dB lower, and there is 30 dB extra transmission loss, you'll get almost all snow.

So why not see what others are doing? Has anyone else tried receving this station in your area? If not, try putting up a half decent antenna (a Yagi tuned to that station) with a pretty good preamp (few dB noise figure, again tuned to that station), and see what you get? Blonder Tongue makes some reasonable stuff--at moderately expensive prices. If you get a good picture, that's great. If you get a snowy picture, you could try a higher mounting point (e.g. a tower) and a better antenna.

Or you could just get local channels from your satellite provider :)

[jcm.oo]

The point of doing this was for HD. Nobody around here uses the digital ota stuff,only cable, (if they can even get cable at their house) or sat. And I Can't get the HD channels off Sat. with Dish. It's the Newport News/VA Beach area stations, from what I can remember one of the stations is transmitting at 700, another is at 1000. The land is very very flat and the tallest building in the area is only 3 stories. There is also some water (the mouth of the chesapeake bay). Dish recently added the locals, but we would like them in HD.

[JM Anthony]

Check out AVS Forum. There are threads for locals. A few months back, there was a discussion on the Seattle thread about some guys close to the Canadian border that are getting good OTA reception of the Seattle locals. If I remember right, they mentioned what equipment they were running. Even though you're not in the Seattle area, there is an incredibly knowledgeable professional installer (Dan Kurtz) who has helped many people with hardware suggestions. I'm one of them.

Good luck.

John

[Spruceman]

For the real technically inclined, maybe this link could help: http://www.cplus.org/rmw/english1.html
Something called Radio Mobile Deluxe...supposed to provide some predictive software. Dont know if it's ILLR or something else. Maybe Ericha could comment on this site/software. It's above me :(

[akron05]

My parents live on a hill in Randolph Township, Ohio, east of Akron. They have a 40 foot tower, a large Channel Master antenna, a pre-amp, and a rotor. They don't have HD yet but refuse to pay for cable and get the following stations clearly:

All Cleveland-Akron-Canton DMA stations

Wheeling Steubenville:

WTRF 7 - usually clear at night, variable during the day (about 70 miles away)
WTOV 9 - usually clear, some snow during the day (65 miles)

Youngstown (towers about 43 air miles)
WKBN 27 - clear as a bell
WFMJ 21 - clear as a bell
WYTV 33 - weak but usually watchable, esp. at night

Once in a while they can pick up Detroit, Toledo, and Columbus stations. Sometimes KDKA out of Pittsburgh, too.

[jtoxxx]

I get good OTA DTV reception at a little over 80 miles with 50' mast the largest Jerrold UHF antenna, a rotor, a preamp and a CATV drop distribution amp to 3 sets. Not a lot of money and very good signal strength. My elevation is high and as far as I can tell a pretty clear path from transmittter to antenna. Get fair reception at over 100 miles depending on climatic conditions.

[Jeff McClellan]

Not bad, whats your location and total number of channels.

[tonyp56]

I'm in Oklahoma, and I live about 70 miles from OKC TV towers, and I pull them in better than the Tulsa stations that are only about 40 miles away, and I pull them in with a STA (set-top-antenna) with amplifier that I paid $30 and some change at Wal-Mart! So it isn't impossible, that is going through my 811 too, so if you got a better quality tuner, and land layout is about the same as it is here (NO mountains) then you should be good to go.

[z0z0]

I am in Toronto Canada and I can pickup HDTV channels from south of Buffalo which is 80 miles away. I use a Winegard SS-2000 and get 30% on the worst channel - which is furthest away, lowest power and lowest antenna height.

Interesting thing for me is that the signal travels about half its distance over water - Lake Ontario.

[83dawg]

I live approx. 53 miles from my station's broadcast towers on hilly terrain (and in the middle of many huge trees).

I have a CM 4228 antenna, 7777 amp and rotor on a 25 foot outdoor pole, and get perfect reception at night (95-100) --- which drops down to 85-88 during the day.

Absolutely put your antenna outside on a pole, and if you are the distance I am from your local towers use the amp. I initially had the antenna on a pole with no amp and I could not get a lock on the signals. I added the CM 7777 amp and immediately began receiving the above-referenced signal numbers.

Good luck!!! There's nothing better than getting free HDTV, especially since the picture on my television screen over the air is better than what I get through my HD package via satellite.

[Pete K.]

As previously noted, there are many variables. What works for one viewer may not for another. I live 70 miles or so from downtown Atlanta. OTA I receive all the Atlanta stations with varying degrees of quality. The best signals by far, come from WXIA-TV, Channel 11 and WTBS, Channel 17(Analog).
This morning, with the help of some tropo activity, I was pulling in a watchable signal from WJCL-TV, Channel 22 in Savannah!

[Cokeswigga]

I'm 70+ miles away from the Los Angeles Antenna farm..
I get ALL the L.A. Stations OTA.

I am using a Winegard HD-9095 with an AP-4700 Pre-amp

My reception with Dish 811 was troublesome,
but with the Dish 622, I have no trouble tuning in any channels.

I have the antenna mounted on a mast that is 10 ft about the highest point of my roof... so about 30' from the ground.

Some channels tune in at 100
while the lowest come in at 74

I think this great reception.

During rain and severe weather it will drop to the 50's and 60's
but once the stupid dish receiver looses a satellite I loose OTA functionality DUE TO THE RECEIVER BEING STUPID.. not loss of OTA signal.

[Neil Edmond]

Greetings folks,

Just popped over here from AVS Forum to check out the info on FTA satellite. But, this OTA HDTV is something I already have considerable experience with. I'm just under 70 miles from one of the seven station I can receive from Memphis TN, and just over 75 miles from the most distant.

We can receive a good signal most evenings from all the stations. Sometimes, when the dewpoint is high, we receive excellent signal from all the stations. Other times, such as during low humidity situations in the middle of the day, we will not be able to catch a watchable signal at all.

We have a CM 4228 w/pre-amp mounted 27ft AGL on a mast. At that height, our antenna is just about ground level with the top of a hill that is about 500ft away and directly in the line of reception. And, the hill is covered with 70ft tall trees. So basically what we're getting is a signal that is either spilling over the trees, or coming through them.

Our channels are on UHF (25. 28, 29, 31, 50, 52, 53) now, but the ones on 52 and 53 will, of course, have to have moved by 2009. They are planning on going to 5 and 13. That will change my antenna needs, but I think it will greatly improve my reception also. As VHF bends much better over the horizon than does UHF, especially high UHF.

[JM Anthony]

Welcome, Neil. It's great to see some of our compadres from AVS Forum crossing over and sharing their expertise here.

John

[socceteer]

has anyone tried this antenna....?

They advertize 70 +

http://www.htmart.com/product.php?productid=105&cat=7&page=1

[Neil Edmond]

Well, that DB8 is basically the same kind of antenna as my CM 4228. Both are eight bay bow-tie designs. But, advertized distance ratings a meaningless. An antenna does not reach out and pull in distant stations. An antenna is more like a transformer. If a RF signal reaches the antenna, that signal will be converted to a voltage that travels through the downlead wire and into the receiver. Now an antenna with a high gain will produce a higher voltage from that original signal than will a lower gain antenna. But both antenna "capture" the same signal. At 70+ miles the most important issue is whether enough signal is reaching the antenna for even a high gain model to generate enough voltage for a receiver to use.

A couple of years ago I had a RS U-75R that gave similar results to the CM 4228 I now have. The RS has about 4dB less gain than the CM (that means it is putting out less than half the power of the CM with the same input signal). When conditions were right, either antenna would do just fine. When conditions are bad, neither will produce a usable signal. When signal conditions are borderline, the CM will give me a usable signal where the RS wouldn't. But at this distance, reception depends more on the weather than on the antenna, in my experience.

[Jim5506]

has anyone tried this antenna....?

They advertize 70 +

http://www.htmart.com/product.php?productid=105&cat=7&page=1
This is the DB-8 by Antennas Direct. As was said it is similar to the CM4228 EXCEPT you notice the reflectors are not continuous across both sets of bowties as they are on the 4228. This means it is virtually useless on VHF, whereas the 4228 does a fair job on high VHF. Oh, and the CM4228 is half the price.

[socceteer]

This is the DB-8 by Antennas Direct. As was said it is similar to the CM4228 EXCEPT you notice the reflectors are not continuous across both sets of bowties as they are on the 4228. This means it is virtually useless on VHF, whereas the 4228 does a fair job on high VHF. Oh, and the CM4228 is half the price.
Thanks I will try that

[ClarkBar]

I am in NE Texas and 66 miles from the only digital station in S. Okla. My antenna is a 15-year old VHF/UHF Channel Master, with several elements blown off and aimed at least 15 degrees away from the tower in Okla. No mast preamp, but a cheap Radio Shack pre-amp in the closet (amplifies the noise?). Antenna on 45 foot tower. Rotor stuck in place.

On a Dish Vip 622, I get a signal from CBS in Okla (66miles) of 85%. A Ph.D. engr. friend out here gets some digital sigs out of Dallas, over 90 miles away. Up to about 90 miles, never say never, unless like me, there is a hill in between. But, before we got satellite TV, we used to get ifffy analog sigs from Dallas on VHF, 96 GPS miles from the broadcast towers. UHF will not reach out as far as VHF, but it is worth a try for anybody out in the sticks. Good yagi, good mast-mount pre-amp, good coax, and antenna up in the air. You never know til you try.

As to Antennaweb dot org, it shows NO digital stations available within range of my rural ZIP code. Well, we know that is not true. I watch a perfect HD picture from CBS in Okla. every night.

[Michael P]

Nope, most stations are planning on staying on their digital frequency.It's not safe to make a blanket statement like this!
In my market (Cleveland) WJW wants to keep it's original ch 8, WOIO wants to
use it's digital assignment ch 10. That's 2 VHF signals in a market that originally had 3 (WKYC, which is analog 3, digital 2 wants to move to a totally different channel, UHF channel 17 which is currently occupied by an analog Canton station WDLI that is digital on 39).

[Michael P]

You have the curvature of the Earth working against you on anything beyond 60 - 70 miles away. Some frequencies may "bend" a little bit, others go straight out, so you would need a giant tower that might need FAA clearances (over 50'??)

[Michael P]

For the record, I get dandy reception from WKBN-DT out of Youngstown ~56 miles away using an indoor Silver Sensor and no amplification. If I used an amp it would overload form all the RF energy in the neighborhood (see my location).

[Michael P]

I just put up a Radio Shack U-75R and aimed it at Youngstown (~57 miles as the bird flies). I now get WKBN-DT 24/7 with an average signal of 103 on my 921.

I'm not as lucky with the other 2 Youngstown stations. So far I have only been able to get a snowy analog picture on WFMJ-TV and a rare, even snowier image from WYTV-TV. I have the digital PSIP data in my guide for all these stations using an indoor Silver Sensor on a day when skip was up (I even snagged 2 Pittsburgh stations at the same time). I tried adding an amp but lost everything in the process. I'm too close to the Cleveland transmitters to mess with amplifiers. The other two stations are not up to full power with their DTV signals yet, so there is hope I'll get them more often once they increase their power. WKBN-DT's coverage map from the FCC shows that it's signal covers from most of the City of Cleveland to most of the City of Pittsburgh! It's the only Youngstown signal that reaches out to the Lake Erie shoreline. And to top it off, it carries a SD FOX affilliate on a subchannel (HD CBS on the main channel). So this one signal will get all the Sunday afternoon NFL action that is available (with several different games carried from the Cleveland market stations throughout the season - last year I counted something like 12 additional games for the whole season when you compair and add the two market's CBS & FOX games) It's like a "poor man's NFLST" :D

One interesting thing about the RS U-75R, it is extremely directional! I though I'd be able to use this antenna for WJW-DT which is 180 degrees from WKBN-DT. The first time I tried WJW, no dice. Now get this, I'm only .8 of a mile from WJW (this is not a typo - that's eight tenths of a mile). Several days later I did get WJW-DT to lock, but with little stability.

I would recommend the RS U-75R for anyone trying for a distant digital signal. I had to have it shipped to a store near me from another store that had it in stock (it's not available from the web). It's an older design but well worth the $24.95 price tag.

[Nomad]

You can't say "at 60 miles it works, at 70 miles it doesn't". There are just too many variables.
A person with a degree in RF engineering (actually this would be more Communications Engineering, which is a different sub-specialty) would build what's called a "Link Budget". It would look something like this:
[...]
Assume:
1) Transmitter power of 100 kW (pretty big, but possible for a UHF station). This is 80 dBm
2) Transmit antenna gain of 3 dB
3) Free space loss at 500 MHz for 70 miles is 128 dB (a pretty big number!)
4) Reciver antenna gain of 10 dB
5) Receiver noise figure of 3 dB
6) No fudge factor for multipath


Nice post from someone who doesn't do this for a living. I have done MANY path studies, having spent 25 years in Broadcast Engineering, then having my own company doing tower and rooftop management, cell site and broadcast station construction and more.

HOWEVER, figure a bunch more antenna gain. The ERP of many UHF DT stations is over one million Watts. The transmitter power is about right (within 6 dB) but antenna gain is MUCH higher than 3 dB, in general. Check the FCC database or call the station for details.

You have the curvature of the Earth working against you on anything beyond 60 - 70 miles away. Some frequencies may "bend" a little bit, others go straight out, so you would need a giant tower that might need FAA clearances (over 50'??)

Yep, and the earth curvature is likely more important than you think.

But, the FAA doesn't GENERALLY get involved until the tower is 200 feet tall or taller. This changes VERY near airports, but in any case all this requires is a light. Still, the light is expensive, AND it requires monitoring, which is expensive. Try to stay under 200 feet.

There are several issues:

First, as the frequency goes up, the signal tends to act more like light, and not want to bend. At VHF, the signal bends pretty well, but at UHF, MUCH less so, and as the frequency in the UHF band goes up, the bending is even less.

VHF antennas have to cover very small segments. VHF Low-band channels cover only 54 to 88 MHz. VHF High-band is only 174 to 206 MHz. UHF is 470 to, well this depends on WHEN you care, but in the end 698 MHz. Having ideal antenna performance over a large range is (antenna manufacturers would say) "difficult." Actually, it is impossible.

SO, look at the actual antenna gain at the frequency you in which you are interested. If all of your channels are low, look at the gain there. If all of them are high, look at the gain there. Different manufactures have different antennas with differnet gains at those band segments. Consider single channel antennas for special uses.


The most important thing is likely to avoid obstacles, including the earth, but also trees and such.

So, YOU ARE GOING TO NEED A TOWER FOR RELIABLE RECEPTION.

If the (local) trees are 60 feet tall, you need a tower taller than them, and any expected growth. You would hate to have a good signal then have the trees grow and ruin the signal.

Next, you need a path study. You can just go buy one, but you can do it yourself. To do it you will need the 7.5 minute maps from the USGS which are covering the path. Get them then plot the path(s). If you don't want to do a bunch of paths, AND the towers are in the same location, you can just select the LOWEST transmitting antenna.

There are tools and methods for bridging from one map to the next, but for the layman, the best method is to just fold over the edge of one map (or cut it off) and tape it to the next map. Lay down a straight edge and draw a pencil line from the transmitter to the receiver. The transmit location is EASY. The coordinates are on the FCC license. The receive location is less so. You MAY see your house on the map, but that depends on many things, including the last time the map was updated and the density of the location. In rural locations, buildings are plotted, but in urban, they are not.

You can use a WAAS enabled GPS receiver.

Anyway, on the map, tick off lines at a minimum of one per mile. In that path, pick the HIGHEST elevation. You should also drive (or fly) the path to see if anything lies in the way, like tall trees, buildings or the cooling towers of a power plant.

Plot the path on graph paper. Now, normal graph paper won't work because you have to take into account the curvature of the earth. Because of some issues of how radio signals REALLY travel, you should use 4/3 (four-thirds) earth curvature graph paper. You can find this on the web sites of companies making microwave radio equipment.

You could also actually calculate your Fresnel Zone clearance based on frequency and your desired reliability. Without going into a detailed explanation, just understand radio signals do not actually go in a straight line like light. Thus, you must have more clearance toward the middle of the path than at the ends. This also changes with frequency. I always shoot for 1.0 Fresnel Zone clearance, but in many industries, 0.6 Fresnel Zone clearance is good enough.

Once you have this graph, with the transmit tower height on one edge, you can lay a straight edge over it, clear any obstructions, and see how tall your receive tower has to be to provide a clear path.

Now, just pulling numbers out of my -- er -- head, knowing how flat it is there, but that there are pine trees which grow tall, I would GUESS you would need a receive tower height of 90 to 100 feet. (FOR GOD'S SAKE, DON'T BUY A ROHN 25 FOR THIS!)

Now, antennas. You need to overcome the "free space loss." Many people think a pre-amp will help bring up receive levels, but this just isn't true. A pre-amp at the antenna being used to overcome receive line loss will help preserve your signal to noise ratio; nothing more, nothing less.

Lower loss cable is a good idea. Andrew sells a entire line of 75 Ohm cable suitable for this use. I suggest Andrew Corporation.

I posted a URL to the Andrew site, but the site won't let me as I have yet to make five posts. You will have to navigate to the Andrew Dot Com site yourself. Once there, append products/trans_line/broadband-cable-tv/heliax-75ohm.aspx

Sure, $2/foot or more might seem extreme, but if you can avoid that pre-amp at the top of the tower, you have fixed a maintenance problem. Expect a mast mounted pre-amp to be taken out of service from time to time by lightning. Low loss cable can eliminate the need for that mast mounted pre-amp and avoid the issue completely.

Antennas are important too. They are "free gain." The higher the gain of the receive antenna, the more signal you will have at the receiver. Keep in mind, as mentioned earlier, gain changes across the band, so you may want to select your antenna carefully.

There is much on the Errornet -- I mean Internet about combining antennas from different directions. Except for the possible case of combining a VHF and UHF antenna, DON'T DO IT!

Multipath is the bane of Digital TV reception, and two antennas invite it. Except when used to increase gain, just don't do it!

Antennas are very important. Andrew and Scala make some very nice, high gain, professional grade antennas. No, don't expect them to cost $60. However, once you have the antenna installed on the tower, do you want to have to replace it in 5 years? If not, go pro. The cost of replacing the antenna is high.

I hope this gets you going in the right direction. Good luck.

[Nick]

Excellent presentation and good advice, Nomad. Even I learned a few things.

Welcome to DBSTalk :wave: and please stick around -- there may be questions.

Here are your links...
www.andrew.com
www.scalaantenna.com

[kenglish]

Now, everyone do what I do.....every time you go to the NAB convention, ask Kathrein/Scala, and some of those other guys, to "Please, please, build us geeks a nice $300 antenna for home use". I just want a solid, weather and snow resistant TV antenna, made to some semi-pro standards.

Is that too much to ask?

[Tower Guy]

Now, everyone do what I do.....every time you go to the NAB convention, ask Kathrein/Scala, and some of those other guys, to "Please, please, build us geeks a nice $300 antenna for home use". I just want a solid, weather and snow resistant TV antenna, made to some semi-pro standards.

Is that too much to ask?

Try one of these:

http://www.wade-antenna.com/Wade/homeantennas.htm

[akron05]

Seems like we went through this before..

at 70 miles, OTA may as well be NoTA unless you have a degree in RF engineering, a large budget and a lot of time on your hands if you ask me.

I know quite a few people getting good UHF at about 75 miles with good equipment, but only over flat terrain or if they're on a hill or otherwise line-of-sight from the station.

[Goobz!]

Anyone here using the OTA antenna that D* offeres!? It seems to work very well on certain channels out here in North Seattle, where the towers are 30-50 miles away.

[JM Anthony]

Anyone here using the OTA antenna that D* offeres!? It seems to work very well on certain channels out here in North Seattle, where the towers are 30-50 miles away.

I suggest you go to AVS Forum, find the Seattle OTA thread and leave a message for "Quarque" with your address and ask for his advice and Dan Kurtz's. Dad does the custom install for Magnolia A/V. Between the two of them, they'll help you out. One of the Channel Masters will probably be your best bet.

Good luck.

John

PS - The Queen Anne and Capitol Hill towers are more like 8-10 miles from Shoreline.

[Goobz!]

I suggest you go to AVS Forum, find the Seattle OTA thread and leave a message for "Quarque" with your address and ask for his advice and Dan Kurtz's. Dad does the custom install for Magnolia A/V. Between the two of them, they'll help you out. One of the Channel Masters will probably be your best bet.

Good luck.

John

PS - The Queen Anne and Capitol Hill towers are more like 8-10 miles from Shoreline.

Well, you know what's funny, is I work with Dan @ Magnolia A/V, and we've all thrown this topic around, especially since living in L.A., I got all the locals on 8x channels.

Just like any other topic, someone never uses the product you have, so they can just guess at the one they use! However, I do know that if I point the OTA at Queen Anne, I get 4-1 99.9%, 5-1 80%, 7-1 75-80%, 9-x 100%, 11-1 50%, 13-1 10% of the time. If I point toward Capitol Hill, they all change and the least I get 100%, and the most 10%..

Anyone ever tried an amp on an OTA to know if it works!?

[oldave]

Nice post from someone who doesn't do this for a living. I have done MANY path studies, having spent 25 years in Broadcast Engineering, then having my own company doing tower and rooftop management, cell site and broadcast station construction and more.

HOWEVER, figure a bunch more antenna gain. The ERP of many UHF DT stations is over one million Watts. The transmitter power is about right (within 6 dB) but antenna gain is MUCH higher than 3 dB, in general. Check the FCC database or call the station for details.Excellent post, but you left out transmission line loss in the link budget calculations.

Obviously, we don't have to concern ourselves with the loss on the transmitter end, since that's calculated into the ERP. But on the receive end, obviously we're going to want as low a loss figure as possible at 75 ohms... few of us are going to be able to afford much more than a good quality RG-6.

Another note... "within 6db" is kinda huge, man :)

[oldave]

Now, everyone do what I do.....every time you go to the NAB convention, ask Kathrein/Scala, and some of those other guys, to "Please, please, build us geeks a nice $300 antenna for home use". I just want a solid, weather and snow resistant TV antenna, made to some semi-pro standards.

Is that too much to ask?Yeah, it is... 'cause the R/D cost is gonna be a bit high, but the market's going to be small.

What us geeks need would end up lookin' like a cable headend... and we can do that today, given sufficient fundage...

And BTW, Ken... is there anyplace I won't run into you? :D