Is it possible to run two leads from single OTA to reduce splitters

[handymantoo]

I have two 722k with OTA, an FM receiver and three TV. The most distant stations are 35 miles away and my signal is in the 70-77 range. Would signal improve if I ran second lead and eliminated some of the splitting. Was considering Wineguard pre amp AP 8780, but would prefer not to use preamp.

 

[boba]

How are you going to run cables without splitting?

You can't just run 2 lines off the antenna connection points. That affects the antenna impedance match and would do more damage than splitter loss.

 

[CowboyDren]

Right; you have to have a splitter somewhere, unless you want to install a second antenna. It helps to have the splitter as close to the first output terminal as possible, though. If your 722s are on top of each other, the splitter should be right behind the boxes. But if one is in another room, the closest one to the antenna should host the splitter, and then a single, short run from that splitter to the second unit.

A preamp will help overcome losses even more, especially if you're talking about more than 50' from the antenna to the first 722. Unless you're in a really noisy area or 3 miles from the towers, go ahead and invest in a preamp.

 

[roashru]

handymantoo, If you are talking about running (2) 300 ohm antenna transformers connected to the antenna and separate coax for each TV down the mast should work but I think the ohms law is you would need (2) 150 to 75 ohm transformers to properly do that or you could just run (1) coax down replace the main splitter with a low noise figure distribution amplifier. cap/terminate any unused f-connectors.

 

[dodge]

handymantoo, If you are talking about running (2) 300 ohm antenna transformers connected to the antenna and separate coax for each TV down the mast should work but I think the ohms law is you would need (2) 150 to 75 ohm transformers to properly do that or you could just run (1) coax down replace the main splitter with a low noise figure distribution amplifier. cap/terminate any unused f-connectors.

Ohms law has nothing o do with it is an Impedance mismatch problem.
Use a preamp and a high quality splitter with a low db loss at each port. also make sure your spliter is swept tested for 2200 mhz or above and cap any unused port with the 75 ohm terminators. I have a 8 way splitter on my antenna and I dont see any loss.

 

[CowboyDren]

also make sure your spliter is swept tested for 2200 mhz or above

Why? I mean, since broadcast TV doesn't get over 700MHz anymore...

 

[JB Antennaman]

Technically, the problem is that each Balun would have about 3 db of loss.

The next problem as we both know is that wire is rated in loss per a foot at X frequency.

The loss at channel 2 - even at 100 feet for a good communications grade RG 6 Quad Shield wire such as the Belden 1829 AC series 6.

Since we know that channel 2 occupies a frequency of about 66 - 72 Mhz - we know that the Belden wire has a loss rate of about 1.4 Db per 100 feet.

At the same time, channel 51 - which is our highest frequency - occupies a frequency of around 692 - 698 Mhz. The loss rate of the same wire might be around 4.6 Db per 100 feet.

So at channel 2 - you would have more then twice the amount of signal at the television after 100 feet of good RG 6 then you would if you wanted to receive channel 51. That is because we know that about 3 db = a loss or gain rate of 50%

To compensate for this, we use some type of amplification to boost the signal to compensate for line loss. The problem with trying to amplify the signal is that a amplifier also produces it's own noise. So we need to keep in mind that we must use a amplifier that has a very low noise factor and does not produce too much amplification or else we will experience over load.

For a fringe signal, that is not a problem, but with FM radio stations in the neighborhood that transmits around 88 - 92 Mhz, it will make more problems than it solves, especially if we are trying to receive something in the low VHF band 2 through 6.

The problem then is - if you tried to use two drops and two Baluns that you would actually increase the amount of loss proportionally with the amount of wire that you attached to the antenna. You would gain nothing and you would loose twice as much signal - which was the reason why you wanted to run two wires in the first place.

Splitters all have loss. A good 2 way splitter usually has about 3.7 Db of loss.

When you move up to a 3 way splitter, you will find that one or more ports might have as much as 7 Db of loss. The reason is that multi way splitters ports are not unilateral.

If a splitter was unilateral, if you walked in the input port, two identical people would walk out of the outputs. Their heads and their hands and their torso's would all be the same exact size.

Unfortunately, it just doesn't work that way. With a 3 way splitter, one person might come out half as big and the other two comes out 1/4 as big as the person that walked into the port.

When you add wire, after the splitter, the loss rate of the wire is proportional to the amount of wire that you add. No matter if the other televisions are turned on or off, you will have a loss rate of the combined length of all the wires connected to the outputs on the splitter.

So if you have 100' of wire after the splitter and 100' of wire before the splitter, you will have a loss rate of the same as if you moved your antenna 200 feet away from the house.

To compensate for this, we sometimes use a distribution amplifier. The problem is - the distribution amplifier also injects noise into the system. So everytime we add a amplifier we are actually making the signal more muddy.

The problem then becomes, you need to have as good of a antenna as you can possibly afford, it needs to be the right size to do the job and it needs to be pointed in the right direction to take advantage of as much signal as it can possibly receive.

If you take crap and butt it into a piece of crap wire and then amplify that crap, all that is going to come out the end is more crap.

If you take a good clean signal and amplify it one time, run it through the best wire and the best terminals and use some type of corrosion protection inside of the terminals, you might get a pretty good signal to come out the other end, with or without some type of amplification - depending on how strong the signals are at your home location.

At the same time, a FM tuner will interfere with your television reception.

It is better to use a dedicated VHF antenna, at a proper distance away from the antenna you use for your television to receive FM signals then to try to use one antenna to receive everything.

In the analog days, it really didn't matter because even if you had signal degregation - you didn't notice it because the signals was transmitted in two parts. You had the audio which was FM and the video which was AM and transmitted at a much higher power level due to the fact that AM was more susceptable to interferace - noise.

Even if you had a poor signal, there might be some snow and some static on the sound, but you could still watch it. With the new lower power Digital signals it is all or nothing.. Either you have a perfect picture and sound, or you have no sound and pixelation or you have no signal at all.

There is nothing in between!

 

[JB Antennaman]

If when you was a kid and you watched cartoons, sooner or later one of the cartoons would have someone strapped to a log and cut in half by a buzz saw.

Each half of the person was the same size - but only half as big in diameter and only had one eye, one hand and one foot. That is what a splitter does. It cannot magnify what ever is coming in, it can only chop it in half and make two smaller size portions.

As I said before with the wire connected to the output ports, the more wire you add, the more loss you will incur.

Old Red Green up there has a magical 8 way splitter that has no loss at any of the ports. When in fact he probably is loosing 12 - 14 db just in the splitter.

To split a signal 8 times, you would need a distribution amplifier, even then it would have some loss because it would inject noise into the equation.

The proper way to split a signal 4 times is to use 3 - two way splitters.

First your split the signal two ways and then you make two small leads which will connect the two ports to two more splitters. Each port on each of those splitters would then be unilateral and each port would have a loss of around 7 Db.

Now you are wondering why would we want to do this?

The reason is because we do not know which ports will have the most amount of loss until we hook a wire up to them. Chances are one television would have good reception - say a upstairs bedroom, while the downstairs living room television might have little or no reception at all in a fringe area.

With a CATV signal, this is not a problem, because the original signal was amplified several thousand times at the head end and the signal coming into your house is very strong.

With a OTA signal, this is not good, because we might have a signal of .00006 milliwatts per a meter of diapole which might be watchable with a pre amplifier and one television, but would be unwatchable with several televisions and no amplification.

So we have to do everything possible to protect that signal.

 

[Splicer]

Holy crap! There is just so much wrong with what you are saying JB Antennaman, I just don't know where to begin to correct you. I'm not quite sure I want to take the time to correct everything. So I'll just correct (and explain) some things that really stick out.

I'll start off with this:

we know that channel 2 occupies a frequency of about 66 - 72 Mhz

What we know is you are wrong. In reality ch 2 occupies a 6MHz space between 54-60 MHz. Channel 4 occupies the 66-72MHz band.

When you move up to a 3 way splitter, you will find that one or more ports might have as much as 7 Db of loss. The reason is that multi way splitters ports are not unilateral.

Actually the first sentence is correct. However this is called an unbalanced 3 way splitter. There is however a balanced 3 way splitter that has equal loss at all ports.

So if you have 100' of wire after the splitter and 100' of wire before the splitter, you will have a loss rate of the same as if you moved your antenna 200 feet away from the house.

Well what you REALLY have is a loss rate of 200' of cable as well as the added loss of the splitter.

The proper way to split a signal 4 times is to use 3 - two way splitters.

This is a completely bogus statement. Not just for the fact that there are now more connection points that can fail. But the fact that there is more loss incurred than using just one 4 way balanced splitter. You need to add an additional 1 dB loss to the splitters 3.5dB loss per 2way splitter. This is due to the .5dB loss for each connection point per splitter.

To split a signal 8 times, you would need a distribution amplifier, even then it would have some loss because it would inject noise into the equation.

Again, this is completely wrong. If the signal is strong enough (ie...reception antenna is close to transmiter location) an 8 way can be used without a distribution amp. But that isn't where you have no idea what you are talking about. Noise from an amplifier has no effect on signal loss, but does affect the quality of the signal.

The reason is because we do not know which ports will have the most amount of loss until we hook a wire up to them.

Wrong, wrong, wrong. We do know which port has the most loss. This is known because we (supposedly) know the input level and we know what the loss is from the splitter itself as the loss is labeled as such.

With a CATV signal, this is not a problem, because the original signal was amplified several thousand times at the head end and the signal coming into your house is very strong.

Your vast knowledge amazes me. The original signal in a CATV headend is not "amplified several thousand times". Not even a tenth of that amount. While the signal into a home is supposed to be (and usually is) strong, it is far from being "very strong".

Damn, this is tiring making all these corrections.

BTW, what is a "diapole"? I presume you meant 'dipole'? Or is there a new piece of equipment only you know about?

 

[boba]

Splicer congratulations for trying to correct a "pro" who needs education.

 

[CowboyDren]

I've been waiting for somebody to do that.

 

[JB Antennaman]

Splicer - whats your problem?

I was trying to make a example, I did not say this is this or that is that.

No splitters that I know of comes right out and says = this port is good and this port is junk.

You can buy sweep tested stuff that is not much better.

I was trying to make a point, the point being that the loss at a low channel is much lower then the loss at a higher channel

The loss in a 8 way splitter is unacceptable - Period.

When you take a crappy signal, butt it into crappy wire and then try to amplify it - once it has traveled down the crappy wire for 100 feet, all that will come out the other end is more crap.

What you want to do is take the best possible signal, amplify it if necessary to compensate for line loss and then send it to the television with as little loss or noise injected into the line as possible.

CATV and OTA signals are not the same!

If you had 1000 miles of television wire connected to the head end of one antenna with no amplification, you would have nothing come out the other end, it would be like connecting a dummy load up to your television.

DC power cannot travel more then 10 miles, as Tom Edison found out more then 100 years ago.

AC power - if amplified can travel over long distances with little problems - which is the reason why we use AC power in the US today. If not, almost every town would have to have it's own power generation station.

I misspelled dipole - so sue me. The computer I was typing on - was lagging and I was typing 20 words a minute and it was showing 5. No spell check and even if there was - it probably wouldn't be in there anyways.

Maybe you ought to stick to little kids and old people where you can impress them with your vast knowledge.

 

[Splicer]

Splicer - whats your problem?

Your incorrect posts.

I was trying to make a example, I did not say this is this or that is that.

You didn't say that what you posted was not this or that. Quite the opposite actually. You posted as fact with no indication that you were not posting as such.

No splitters that I know of comes right out and says = this port is good and this port is junk.

What are you talking about? Do you even know yourself? Because nobody else does.

You can buy sweep tested stuff that is not much better.

Again, what are you talking about? Or are you just neither saying this or that?

I was trying to make a point, the point being that the loss at a low channel is much lower then the loss at a higher channel

You failed miserably instead of just coming out and saying this.

The loss in a 8 way splitter is unacceptable - Period.

No. No it isn't. There is a reason 2, 4, 8, & 16 way splitters are manufactured.

When you take a crappy signal, butt it into crappy wire and then try to amplify it - once it has traveled down the crappy wire for 100 feet, all that will come out the other end is more crap.

First off nobody has contradicted this statement. Second off you should have just said, 'crap in and amplified will only give you amplified crap out' and gotten your 'point' across much better than the rambling way you posted.

What you want to do is take the best possible signal, amplify it if necessary to compensate for line loss and then send it to the television with as little loss or noise injected into the line as possible.

Well, seeing as I said this already, when correcting you no less, this isn't anything new.

CATV and OTA signals are not the same!

Do tell.

If you had 1000 miles of television wire connected to the head end of one antenna with no amplification, you would have nothing come out the other end, it would be like connecting a dummy load up to your television.

No antenna has a "head end", at least not in the manner you wrote. Regardless, nobody has said anything different so, what are you talking about and why?

DC power cannot travel more then 10 miles, as Tom Edison found out more then 100 years ago.

And this has to do with this topic why?

AC power - if amplified can travel over long distances with little problems - which is the reason why we use AC power in the US today. If not, almost every town would have to have it's own power generation station.

And again, why are you even posting this completely non topic related information?

I misspelled dipole - so sue me. The computer I was typing on - was lagging and I was typing 20 words a minute and it was showing 5. No spell check and even if there was - it probably wouldn't be in there anyways.

So now you want to take offense when I asked a honest question? I believe I even asked if dipole wasn't what you meant. Then you try to blame a "lagging" computer for the error. And to top it all off you now have the knowledge that a spell check for a site that specifically uses that word on a regular basis would not be in the database. You could try proof reading before hitting the submit button. With your great knowledge you would have easily spotted the error (it was at the very end of the post) and corrected it, even if the computer was "lagging", which has nothing to do with your mis-spelling by adding letters.

Maybe you ought to stick to little kids and old people where you can impress them with your vast knowledge.

Now couldn't you come up with a better insult than this? (Actually it is a rhetorical question that doesn't need an answer from you, since it is obvious this is all you could come up with since it is what you posted.)

Now that that has been said, I would like to get back to some factual information pertaining to this thread. So this basically excuses you from posting here again JB Antennaman, since you, thru your own admission

did not say this is this or that is that

and as such makes your replies irrelevant and insignificant.

 

[Mr Tony]

I've been waiting for somebody to do that.

I did that once too to the "expert"

If you notice, old JB likes to post off topic stuff and be wrong all the time then whines that he's being picked on

He tried the same thing when I posted that a station had gone off the air back in June due to no money to convert to digital. Then when they did get back on air a month ago, he decided to post some off topic stuff about how subchannels work and then some wrong info like you can only own one station in a market which considering we have 2 duopolies here in Minneapolis obviously that is wrong

Here is that thread
http://www.satelliteguys.us/digital-over-air-ota/179430-knrr-pembina-nd-goes-silent.html

so congrats splicer for giving the CORRECT information

 

[Tower Guy]

I have two 722k with OTA, an FM receiver and three TV. The most distant stations are 35 miles away and my signal is in the 70-77 range. Would signal improve if I ran second lead and eliminated some of the splitting. Was considering Wineguard pre amp AP 8780, but would prefer not to use preamp.

Don't go by the signal strength display, use your eyes. If the picture never studders or freezes on any of your TV sets, you have enough signal.

The AP 8780 is an excellent preamp, but it has very high gain on UHF. The knowledge needed to select a high gain preamp is to know the exact specifics of the strongest signal, not the furthest or weakest plus the antenna model number. If you want specific advice, post your tvfool report.

 

[handymantoo]

Tower Guy the following is info from Tvfool.com. The problem I have is I am located near Providence stations so they have a strong signal even though the antenna is pointed toward Boston stations which are the ones I am trying to reach. Could I use a preamp for the Boston stations and turn it off for the few times I may want the Providence stations? The antenna is on a rotor. thanks,
TV Fool

 

[Tower Guy]

Could I use a preamp for the Boston stations and turn it off for the few times I may want the Providence stations?

That idea would work well, but the implementation would not be easy.

In your case I'd use two antennas, both the HD76XX series. The smallest would be fine for Providence. The one aimed at Boston could be larger and should have a HDP-269 preamp, the Providence antenna would have no preamp. Next I'd install two wires to each TV and put an A/B switch at each TV set.

Even a small side mounted EZ HD would be fine for Providence.

 

[CowboyDren]

Why wouldn't you just use a $13 Winegard CC-7870 joiner, which could take an amped input on one side and an unamped input on the other side, thus allowing a single downlead into the house?

Also, I like the HD-76xx series, but I think it's overkill. At only 9 miles out, a 2-bay bowtie (HD-1080, $25) will probably work with Providence Fox-64 (WNAC, rf12); at least my DTV2B-UHF worked fine on rf9 from 8 miles out. Also, by swapping the 65-inch-long combo antenna for Boston, and going to a 4-bay bowtie (HD-4400, $24), the only channel that it's not designed for is WWDP-46 (rf10). Of course, since they're both bowties with pretty wide beam widths, you'd need to put some serious separation between them, like 3'.

Just offering options. Yes, I'm a bowtie fanboy.