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How long can coax cables go and any conflicts before HDTV OTA signal losses? - Page 2

post #31 of 55
Quote:
Originally Posted by Ratman View Post

Maybe he doesn't need a pre-amp or distribution amp.

If you looked at his TV fool report and you paid attention that he has his antenna hooked to 4 TVs with some runs nearing 100 feet, I'd say he needs some kind of amp.
post #32 of 55
Quote:
Originally Posted by phildaant View Post

I already did. Not all the same. It seems like the farther rooms are weaker. Hence either cables are bad/old or something else.

Well the longer the cable the more loss in signal as I've stated before. That is most likely answer.
post #33 of 55
Quote:
Originally Posted by BCF68 View Post

If you looked at his TV fool report and you paid attention that he has his antenna hooked to 4 TVs with some runs nearing 100 feet, I'd say he needs some kind of amp.
I did look at the report and have "paid attention" that he has 4 TV's.

If you paid attention, you would see that the primary TV (shortest run) is fine. The longer runs are problematic. So, that may indicate that a pre-amp may overload the primary TV's tuner. So... assuming all of his cable, connectors, and splitters are good, I would agree that a signal amp (for the longer runs) may be necessary.
post #34 of 55
Thread Starter 
Quote:
Originally Posted by Ratman View Post

I did look at the report and have "paid attention" that he has 4 TV's.
If you paid attention, you would see that the primary TV (shortest run) is fine. The longer runs are problematic. So, that may indicate that a pre-amp may overload the primary TV's tuner. So... assuming all of his cable, connectors, and splitters are good, I would agree that a signal amp (for the longer runs) may be necessary.
Actually, it is just currently two TVs right now (will get HDTVs later on):
1. An old small CRT TV + Zeinth DTT900 converter box.
2. A portable Digital Prism ATSC DTV (easy to carry and move with) to try in all rooms with coax cables from the walls.

Just remember that these coax cables, connectors, etc. are from the previous owners' Dish TV service. The house is from the early 1980s/80s, so who knows how long they had these. Like I said mentioned earlier, one of the room's coax cable had that power AC connected. Someone said that this was for that small Dish satellite dish receiver on the roof.
post #35 of 55
Quote:
Originally Posted by Ratman View Post

I did look at the report and have "paid attention" that he has 4 TV's.
If you paid attention, you would see that the primary TV (shortest run) is fine. The longer runs are problematic. So, that may indicate that a pre-amp may overload the primary TV's tuner. So... assuming all of his cable, connectors, and splitters are good, I would agree that a signal amp (for the longer runs) may be necessary.

I seriously doubt an amp will overload his tuner when his "best" signal is 22 NM( dB ). I have similar signals with my strongest channel and I never have overloaded it with a pre-amp. Unless he's got some magical 40 dB pre-amp I'll say I'm 100% positive he won't.
post #36 of 55
Hopefully you're correct and the OP will let us know how his issues are resolved.

I just think that there may/could be other issues (which haven't been thoroughly checked) other than low signal on a 100' run of RG6.
Edited by Ratman - 7/1/12 at 2:21pm
post #37 of 55
Thread Starter 
Quote:
Originally Posted by Ratman View Post

Hopefully you're correct and the OP will let us know how his issues are resolved.
I just think that there may/could be other issues (which haven't been thoroughly checked) other than low signal on a 100' run of RG6.
It won't be this weekend due to other plans. What other issues could it be? Interferences? Old ages?
post #38 of 55
As suggested earlier:
Bad/corroded connectors
bad splitters
bad/inferior coax
perhaps interference - depends where/how the problematic coax is run (parallel to A/C power lines)
- ingress due to bad cable/connectors
post #39 of 55
Thread Starter 
Quote:
Originally Posted by Ratman View Post

As suggested earlier:
Bad/corroded connectors
bad splitters
bad/inferior coax
perhaps interference - depends where/how the problematic coax is run (parallel to A/C power lines)
- ingress due to bad cable/connectors
Yeah, they're probably all old. There's an AC unit next to the garage near the Dish satellite and coax cables. Would this interfere even though it is not used?
post #40 of 55
Thread Starter 
Quote:
Originally Posted by BCF68 View Post

They go to as many TV's as you want. The port that goes out the the TV you would connect to the cord going into the house that connect all the TVs. .Anyways unless they've changed Radio Shack amps have always been crap. Also I don't think those are for outdoor which would make them amps not pre-amp. You need a pre-amp.
If they are craps and not preamps (I am glad you noticed that before I bought one [was going to do that for the weekend. I did find http://www.radioshack.com/product/index.jsp?productId=11095347 , but no local stores have it), then what preamps (already in stock) to get from local retail stores (Fry's Electronics, Best Buy, Costco, Walmart, etc.)? Is it me or is it really hard/difficult to find pre-amps in local retail stores? frown.gif
Edited by phildaant - 7/1/12 at 11:10pm
post #41 of 55
Thread Starter 
Quote:
Originally Posted by phildaant View Post

Would these preamps be OK from Radio Shack to try and return if needed?
1. http://www.radioshack.com/product/index.jsp?productId=3770519 (Model: 15-321 | Catalog #: 15-321)
2. http://www.radioshack.com/product/index.jsp?productId=3780245 (Model: 15-259 | Catalog #: 15-259)
Reviews are three and four stars, and they only go to two TVs. At least, they can be returned. wink.gif
I contacted Radio Shack through its web site a couple days ago and got this e-mail response/reply yesterday:

"Date: Sat, 7 Jul 2012 15:35:06 -0400 (EDT)
From: "RadioShack.com"
To: Ant
Subject: Re: I need help finding a product
x-mailer: KANA Response 8.2.0.30.6

Dear Ant,

Thank you for contacting RadioShack.com.

We appreciate your inquiry and would be happy to assist. After careful
review of the products you've included in your questions, we believe we
have located all the information you require.

Our review indicates the products both do not work as a
pre-amplification device for your coaxial cable signal. The catalog
number 15-321 boasts a amplification of 40 decibels while the catalog
number 15-259 indicates the amplification is approximately 20 decibels.
At this time we have been unable to determine the measurement for
additional noise potentially generated by the devices..."

So it confirms that these amps are not for what I need for my situation. frown.gif Ugh, I will have to keep searching for a local Los Angeles/L.A. area store with pre-amps.


A newbie question: Do all pre-amps require power connections? Or are there actually pre-amps that don't require it? The reason for this is because the attic where the coax cables and splitter to the outdoor CM-4228HD antenna does not have a power outlet. frown.gif
Edited by phildaant - 7/8/12 at 12:15pm
post #42 of 55
BS from RS... biggrin.gif
I will agree with "...unable to determine the measurement for
additional noise potentially generated by the devices...". I would say again... check cables, connectors, yada, yada...
Amps will amplify all signals, bad and good. Amplifying a bad signal or noise just adds to the problem.

Pre-amps (at the antenna) are powered via the coax cable from an external power supply. The power supply for the pre-amp can be installed anywhere.
Edited by Ratman - 7/8/12 at 2:26pm
post #43 of 55
Thread Starter 
Quote:
Originally Posted by Ratman View Post

BS from RS... biggrin.gif
I will agree with "...unable to determine the measurement for
additional noise potentially generated by the devices...". I would say again... check cables, connectors, yada, yada...
Amps will amplify all signals, bad and good. Amplifying a bad signal or noise just adds to the problem.
Pre-amps (at the antenna) are powered via the coax cable from an external power supply. The power supply for the pre-amp can be installed anywhere.
I didn't know coax cables can be used for power. So it is like that Dish power adapter (can't reuse it for OTA from another post) from a few months ago.
Edited by phildaant - 7/8/12 at 2:44pm
post #44 of 55
Quote:
Originally Posted by phildaant View Post

I
So it confirms that these amps are not for what I need for my situation. frown.gif Ugh, I will have to keep searching for a local Los Angeles/L.A. area store with pre-amps.
A newbie question: Do all pre-amps require power connections? Or are there actually pre-amps that don't require it? The reason for this is because the attic where the coax cables and splitter to the outdoor CM-4228HD antenna does not have a power outlet. frown.gif

Yes pre-amp requires power. The difference between an amp and pre-amp is the pre-amp is close to the antenna while the power source can be inside far away. A regular amp will be close to the power source and they are not made for outside installation or attic really either.

You will most likely have to get a pre-amp online. Wal-Mart sells this pre-amp online I'm not sure if some store carry it though. And I can't speak for the quality since I don't have any experience with it but it's cheap.

http://www.walmart.com/ip/RCA-Antenna-Pre-Amplifier/14554631
post #45 of 55
Thread Starter 
Quote:
Originally Posted by BCF68 View Post

Yes pre-amp requires power. The difference between an amp and pre-amp is the pre-amp is close to the antenna while the power source can be inside far away. A regular amp will be close to the power source and they are not made for outside installation or attic really either.
You will most likely have to get a pre-amp online. Wal-Mart sells this pre-amp online I'm not sure if some store carry it though. And I can't speak for the quality since I don't have any experience with it but it's cheap.
http://www.walmart.com/ip/RCA-Antenna-Pre-Amplifier/14554631
Thanks. Yeah, that one requires to be ordered online. That one is an interesting design unlike other pre-amps I have seen.
post #46 of 55
Thread Starter 
Quote:
Originally Posted by phildaant 
Like I said mentioned earlier, one of the room's coax cable had that power AC connected. Someone said that this was for that small Dish satellite dish receiver on the roof.
FYI, http://zimage.com/~ant/MiCasa2/DisconnectedDishPowerACwithCoaxCableOutlet.jpg for that power AC since I found it again and had my old digital camera with me this time. I tried connecting its power AC to the coax cable outlet (didn't reuse its coax cable since its screw was stuck) and power outlet to see if it did anything for OTA. Nope as we expected!
post #47 of 55
Thread Starter 
Quote:
Originally Posted by BCF68 View Post

Yes pre-amp requires power. The difference between an amp and pre-amp is the pre-amp is close to the antenna while the power source can be inside far away...
Wait, if the pre-amp is far away to be next to the antenna, then how will it get power from its AC? Is it set up like that Dish's power AC adapter that I mentioned in my previous/last post and power goes through the coax cables?
post #48 of 55
Quote:
Originally Posted by phildaant View Post

Wait, if the pre-amp is far away to be next to the antenna, then how will it get power from its AC? Is it set up like that Dish's power AC adapter that I mentioned in my previous/last post and power goes through the coax cables?

FWIW, my pre-amp is in the garage connected to an outlet. It's at least 100' away from the antenna. The RG-6 connects to the input and then I have a 3-way splitter about 2" away that sends to signal to the house and garage. For us, it works just fine.
post #49 of 55
Thread Starter 
Quote:
Originally Posted by Otto Pylot View Post

FWIW, my pre-amp is in the garage connected to an outlet. It's at least 100' away from the antenna. The RG-6 connects to the input and then I have a 3-way splitter about 2" away that sends to signal to the house and garage. For us, it works just fine.
So, power goes through the coax cables to boost the antenna's feed to the tuners throughout the house?
post #50 of 55
If the preamp is installed properly (preamp at antenna, power supply indoors), the power supply sends DC voltage to power the preamp via the antenna's coax feed. That boosts the signals received at the antenna, which is then carried back to the TV(s). The DC voltage is blocked from going to the TV(s) by the power supply.
post #51 of 55
Thread Starter 
Quote:
Originally Posted by Ratman View Post

If the preamp is installed properly (preamp at antenna, power supply indoors), the power supply sends DC voltage to power the preamp via the antenna's coax feed. That boosts the signals received at the antenna, which is then carried back to the TV(s). The DC voltage is blocked from going to the TV(s) by the power supply.
Interesting and thanks.
post #52 of 55
Thread Starter 
Hello.

Just in case I still need to buy a pre-amp for the outdoor CM-4228HD antenna to the attic and then into the four rooms. Is this Rocketfish™ Bidirectional Mini Drop Amplifier (Model: RF-G1179) considered a pre-amp and good enough to try? It is about $41 in local Best Buy stores (returnable): http://www.bestbuy.com/site/Rocketfish%26%23153%3B+-+Bidirectional+Mini+Drop+Amplifier/9449135.p?id=1218106370284&skuId=9449135&st=RF-G1179&cp=1&lp=1 ...

It has a power AC adapter. http://www.rocketfishproducts.com/products/home-theater/RF-G1179.html for the official web site, and a quick setup PDF: http://www.rocketfishproducts.com/cms/documents/QSG/RF-G1179_09-0635_QSG_V2_Final_lr.pdf ...

Thank you in advance. smile.gif
Edited by phildaant - 7/22/12 at 9:58pm
post #53 of 55
Quote:
Originally Posted by phildaant View Post

Hello.

Just in case I still need to buy a pre-amp for the outdoor CM-4228HD antenna to the attic and then into the four rooms. Is this Rocketfish™ Bidirectional Mini Drop Amplifier (Model: RF-G1179) considered a pre-amp

No.
post #54 of 55
Thread Starter 
Quote:
Originally Posted by domino92024 View Post

No.
Thank you for the confirmation. smile.gif
post #55 of 55
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