Propper placement of distribution amp for OTA HDTV? - AVS Forum
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post #1 of 14 Old 07-30-2014, 07:07 PM - Thread Starter
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Propper placement of distribution amp for OTA HDTV?

Hello all:

Cutting the cable this week. I have a home made antenna that works ver well, but I want to send the signal all over the house. So far I have it to 2 TV's that are pretty close to the antenna, but the next TV is probably 100ft. of cable away.

Here is the layout so far:



So, should I put an amp before the first splitter at (1), replace the first splitter at (2), or replace the second splitter at (3)? Like I said, right now the Living room and Bedroom both have enough signal, so I know it's good until I add more in.

Also, I was thinking of getting the BestBuy Rocketfishâ„¢ - Bidirectional Mini Drop Amplifier (4-way). Is that a decent enough amp for this limited setup?

Unfortunately running new cable is out of the picture for now. Also, adding an antenna to the bonus room is out of the question because of house orientation; I can never get a good signal from in there since it has to cut through the rest of the house (and I can't outside mount).

Thanks for any help!
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post #2 of 14 Old 07-30-2014, 07:17 PM
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The Rocketfish is a mediocre amp, at best. Good choices would be the PCT/Channel Master amps, the Antennas Direct 4 or 8 port amps, or Electroline amps. All are very, very good.

The need for an amp is determined by the available signal power and the cabling scheme's requirements. If you're moderately close to your towers and the signals are strong, then you can run a large number of splits with long cable runs and still have adequate power for reliable reception. OTOH, if you're in a weak to modest signal area, you may be pretty close to the digital cliff edge and it won't take much cabling or splitter loss to push your reception off the digital cliff. If you don't want to go through the math exercise, then just split the signal until it fails then back up some.
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post #3 of 14 Old 07-30-2014, 07:31 PM - Thread Starter
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Originally Posted by ProjectSHO89 View Post
The Rocketfish is a mediocre amp, at best. Good choices would be the PCT/Channel Master amps, the Antennas Direct 4 or 8 port amps, or Electroline amps. All are very, very good.
Do you know if any B&M stores sell those? Looking to get something quick if I can to test for a bit before killing my TWC service.

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Originally Posted by ProjectSHO89 View Post
The need for an amp is determined by the available signal power and the cabling scheme's requirements. If you're moderately close to your towers and the signals are strong, then you can run a large number of splits with long cable runs and still have adequate power for reliable reception. OTOH, if you're in a weak to modest signal area, you may be pretty close to the digital cliff edge and it won't take much cabling or splitter loss to push your reception off the digital cliff. If you don't want to go through the math exercise, then just split the signal until it fails then back up some.
Ok, thanks! Like I said, the 2 I have hooked up now have NO drops in signal on the 4 main stations I need (FOX, NBC, ABC, CBS) since the antenna, although inside, is darn near line of sight to the towers 36 miles away.
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post #4 of 14 Old 07-30-2014, 08:19 PM
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If I had this cabling arrangement I'd put a CM3410 at (1) and add a 6 dB attenuator to the output of the 2-way splitter at (2) that goes to the bedroom and leave the rest of it alone. With the current setup you have about 20 dB of loss by the time the signal gets to the Bonus room TVs. That's a lot plus an indoor antenna is a strike against you even though it seems to be okay now.
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post #5 of 14 Old 07-30-2014, 08:48 PM - Thread Starter
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Originally Posted by Calaveras View Post
If I had this cabling arrangement I'd put a CM3410 at (1) and add a 6 dB attenuator to the output of the 2-way splitter at (2) that goes to the bedroom and leave the rest of it alone. With the current setup you have about 20 dB of loss by the time the signal gets to the Bonus room TVs. That's a lot plus an indoor antenna is a strike against you even though it seems to be okay now.
Thank you as well for this advice. The signal seems to be fine on the Bonus Room TV tonight as long as I have one one hooked up and the splitter removed. This isn't a problem, I can keep the old CRT unhooked.

My only concern I think will be later if there is a storm or anything. I am totally new to this OTA stuff. Would any amplification help in those conditions? Or would it stay or drop regardless?

I see that the Rocketfish is only 4db of amplification; I guess that's not going to put a big dent in that 20db loss, haha.
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post #6 of 14 Old 07-30-2014, 09:43 PM
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Originally Posted by gohanssjn View Post
Thank you as well for this advice. The signal seems to be fine on the Bonus Room TV tonight as long as I have one one hooked up and the splitter removed. This isn't a problem, I can keep the old CRT unhooked.

My only concern I think will be later if there is a storm or anything. I am totally new to this OTA stuff. Would any amplification help in those conditions? Or would it stay or drop regardless?

I see that the Rocketfish is only 4db of amplification; I guess that's not going to put a big dent in that 20db loss, haha.

It's a 4-way splitter so the amplifier is actually 11 dB gain. The CM3410 is 15 dB gain but has no splitter built in. You could replace (1) and (2) in your first post with a CM3412; a distribution amp with 2-way splitter built in.

With an indoor antenna there are not really any lightning issues. Are you asking about dropouts caused by lightning generated noise on VHF? An amplifier can not fix that.
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post #7 of 14 Old 07-31-2014, 04:33 AM
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Do you know if any B&M stores sell those?
MicroCenter carries the Antennas Direct CDA4, according to their website. Fry's used to carry some Channel Master stuff, but I haven't been to one of their store in several years. I'd avoid the Radio Shack stuff - overpriced for mediocre performance.

In a pinch and if you have an electric outlet near your splitter, you could pick up the $15 indoor RCA amplifier (AMP1450R) from Walmart and give it a try. It's actually surprisingly decent for its price and brand.
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post #8 of 14 Old 07-31-2014, 07:30 AM
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Originally Posted by gohanssjn View Post
...I need (FOX, NBC, ABC, CBS) since the antenna, although inside, is darn near line of sight to the towers 36 miles away.
My concern, when amplifying signals from a tower area 36 miles away, is that there my be a local FM transmitter nearby that will overwhelm them in an amplifier. If you don't have any real channels below channel 7, then you can put an inexpensive ($3) device called an HLSJ on the input side of the amp to wipe off all the FM signals.
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post #9 of 14 Old 07-31-2014, 11:22 AM
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Originally Posted by AntAltMike View Post
My concern, when amplifying signals from a tower area 36 miles away, is that there my be a local FM transmitter nearby that will overwhelm them in an amplifier. If you don't have any real channels below channel 7, then you can put an inexpensive ($3) device called an HLSJ on the input side of the amp to wipe off all the FM signals.
Won't that filter out the UHF channels as well?
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post #10 of 14 Old 07-31-2014, 03:24 PM
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Won't that filter out the UHF channels as well?
No. It will only filter out the stuff below the high-VHF band.

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post #11 of 14 Old 07-31-2014, 04:49 PM
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As mentioned, Fry's sells the Channel Master distribution amps. You could possibly get the 3414 version with 4 ports and service all 4 TVs.
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post #12 of 14 Old 07-31-2014, 09:31 PM - Thread Starter
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Thank you all for the help.

The only thing I could find locally (aside from what I first posted) was the RCA amplifier. I put that just after 2 before the next splitter. If I put it at 1 the TV in the bedroom could not scan. So far all TV's are picking up TV well and it looks like we'll be dropping our cable in a week or so once we clear our DVR.

Thanks again!
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post #13 of 14 Old 08-02-2014, 02:07 PM
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Quote:
Originally Posted by gohanssjn View Post
Hello all:

Cutting the cable this week. I have a home made antenna that works ver well, but I want to send the signal all over the house. So far I have it to 2 TV's that are pretty close to the antenna, but the next TV is probably 100ft. of cable away.

Here is the layout so far:



So, should I put an amp before the first splitter at (1), replace the first splitter at (2), or replace the second splitter at (3)? Like I said, right now the Living room and Bedroom both have enough signal, so I know it's good until I add more in.

Also, I was thinking of getting the BestBuy Rocketfishâ„¢ - Bidirectional Mini Drop Amplifier (4-way). Is that a decent enough amp for this limited setup?

Unfortunately running new cable is out of the picture for now. Also, adding an antenna to the bonus room is out of the question because of house orientation; I can never get a good signal from in there since it has to cut through the rest of the house (and I can't outside mount).

Thanks for any help!
As a tech that has hundreds of satellite,cable,and antenna installation & service I recommend dropping a line from the antenna to the existing cable ground block once cable service is disconnected. Your drawing shows many uneven splits. Your existing cable wiring configuration is likely to have much more "even" splits already terminated with good quality coax & fittings.

See if that works before reconfiguring your setup and installing an amp. If an amp is needed, get a mast mounted amp and "backfeed" power from the closest outlet in your home. Backfeeding power will require a power passing splitter.
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post #14 of 14 Old 08-02-2014, 03:25 PM - Thread Starter
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Originally Posted by nyctveng View Post
As a tech that has hundreds of satellite,cable,and antenna installation & service I recommend dropping a line from the antenna to the existing cable ground block once cable service is disconnected. Your drawing shows many uneven splits. Your existing cable wiring configuration is likely to have much more "even" splits already terminated with good quality coax & fittings.

See if that works before reconfiguring your setup and installing an amp. If an amp is needed, get a mast mounted amp and "backfeed" power from the closest outlet in your home. Backfeeding power will require a power passing splitter.
Well I actually put the amp right after (2) and get a clear signal throughout the house, so I am going to leave it that way for now.

Thanks though!
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