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Discussion Starter · #1 ·
Hi,


I'm in the process of running coax & RG6 through my house. My service provider is Comcast. Since I'm running to 5 outlets in my house, not to mention splitting before the cable modem, I'm thinking I will probably need a drop amp (See attached image).

I figured I'd go with a 1-port amp and a 6-port splitter and then just terminate the last port on the splitter. The other option is to buy an 8-port amp and just terminate the ports I'm not using. I don't think I'll ever use more than 6-ports so I figured going with the 1-port amp/6-port split is the best choice. Agree/Disagree/doesn't matter much?


Additionally, when deciding on an amp, I was told by Comcast that I'll need to also amplify the return signal since the cable boxes need to send data back to Comcast for pay-per-view requests and such. Most of the amps have come across are passive returns which makes me wonder why this seems to be the norm with most amp. One would think if most people with cable boxes would use pay-per-view that most amps would be active return. Am I understanding the concept correctly?


Lastly, can you suggest a good drop amp/splitters as well as brands I should stay away from?


Thanks,
 

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Either amplification method would work. Whatever is cheapest i would say.


As for return path amplification. i have found in my experience that the return path is much more stable to being split. I have done hundreds of jobs splitting signals to anywhere from 8 to 40 tv locations and only needed a return path amplifier once and the cable guy told me that the signal from the tap was low and he added the amplifier instead of putting in a plant ticket to correct the tap for a quicker solution.
 

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I would go with option A, having each outlet homerun and utilizing a 1 out drop amp with the necessary splitter. If your needs were to change in a couple of years, it would be easy to change your system -- merely change out the splitter.


I also vote for the passive return path.
 

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Discussion Starter · #4 ·
That's for responding so quickly.

I think I need a little clarification on a few things.
Question: What do you mean by, "the return path is much more stable to being split"

I assume you mean that the return path doesn't suffer much by being split. I just assumed the signal coming from the source (IE: Comcast) suffered just as much as the return path (IE: Back to Comcast) by being split.


Question: What is a "plant ticket"?



As far as Comcast putting in an amp. They won't without charging me about $50.

With the 1-port amp/6-way splitter option is I could put in the splitter and if there was a need to amplify the signal, I'd just add in the 1-port amp.

If the signal is poor, I could first try asking Comcast to boost it. If that doesn't work, I'd just order a 1-port amp online (which will take a few days).

Question: If I only use 2 lines and terminate the rest off of a 6-way splitter, is there a chance I could get a decent signal while I wait for my amp to arrive OR does it even matter to the signal if I use every port or not.


I'm now enjoying running the cable through my attic. I just love the dust, tight spaces and that itchy feeling insulation gives me.
 

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It isn't that the return path is more stable than the forward path. It's that the attenuation through the coaxial cable is much lower than that of the forward path, and the output of the devices that transmit on the return path is very high. The loss through the passive devices is also a little bit less.


A splitter loses x amount of signal strength on all ports, regardless of how many of them are actually in use. For example, +15dBmV goes into an 8-way splitter. Each port will have ~3.5dBmV coming out of it. Doesn't matter if there is even anything connected to any of the ports or not.
 

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Discussion Starter · #6 ·
Ah. Good to know about the return path. I didn't know that.


OK. Thanks for the confirmation on that. Although I knew how much got split, I could never find anything that said if there was nothing drawing signal that the signal was still split. All I found about unused ports is make sure I terminate them.


Thanks again.
 

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Discussion Starter · #7 ·
Another quick question.


I started shopping online for a 6 way splitter. I noticed that most ran between 5 - 900/1000 mhz, which is ideal for cable but if I ever wanted to go to satellite, I understand that's higher up the frequency. If that's the case, if I do choose to go to satellite, I would assume I would need to replace that 6-way splitter.

I noticed there was a wide band splitter (Perfect Vision PV23-406) that went from 5 - 2300 mhz range but since I couldn't find much detailed info on this product, that really concerns me.

Are there any disadvantages from going with a wide band splitter when using cable?
 

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Quote:
Originally Posted by Justin Payne /forum/post/18325926


Another quick question.


I started shopping online for a 6 way splitter. I noticed that most ran between 5 - 900/1000 mhz, which is ideal for cable but if I ever wanted to go to satellite, I understand that's higher up the frequency. If that's the case, if I do choose to go to satellite, I would assume I would need to replace that 6-way splitter.

I noticed there was a wide band splitter (Perfect Vision PV23-406) that went from 5 - 2300 mhz range but since I couldn't find much detailed info on this product, that really concerns me.

Are there any disadvantages from going with a wide band splitter when using cable?

Not really any disadvantages, but no advantages, either. You can't use splitters with Dish Network, and the splitters for DirecTV have to go down to 2MHz, not 5 and must be DirecTV approved. If you ever do go satellite, your splitter would get replaced with the appropriate device.
 

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Discussion Starter · #9 ·
Thanks. That's good information. Bad for the pocket book but good for the info. :-D


I appreciate the sharing of knowledge.
 

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Discussion Starter · #10 ·
Might I request someone make a glossary so us layman's (or laypeople, if you prefer) can understand all of this.



I found two 1-port amps that I'm trying to decide on (but not hard set so if you have a better option, just let me know). It's between the Motorola 484095-001-00 and the PCT MA2-M.

The positives about the Motorola is that they have it available at my local Fry's for the same price as it is on Amazon so I can just drive down and pick it up. It also comes with cables, including power. I have plenty of coax so it's not a big deal but it's nice to have compression connection. It's also a Motorola product, which is a well known name, not that it's always a good thing.

The negatives about the Motorola is that the specs are light. In fact, their own web site is pathetic on the specs. I had to rely on what was provided by Fry's

The positives for the PCT is that it's a little cheaper ($29 to the Motorola's $36) and I have also found more detailed specs, which appear to be similar to Motorola's but slightly better in some areas

The negatives is that I will have to order it online and I'll have to make a power cable with my pathetic crimp tool.


The Motorola seems to be a better choice but I noticed that the return loss is only 18 db+/- on the PCT and 25 db +/1 on the Motorola.

Here is what I have for specs. Please let me know what you think.


MOTOROLA

Tech Specs * Forward Specifications (52-1000 MHz) - Nominal*

o Gain: 15dB

o Input Return Loss: 25dB

o Output Return Loss: 25dB

o Noise Figure: 2.5 dB maximum

o RFI Shielding: 100 dB minimum


* Return Specifications (5-40 MHz) - Nominal*

o Insertion Loss: 1 dB

o Input Return Loss: 25 dB

o Output Return Loss: 25 dB


* Other Specifications*

o AC Power Supply Input Voltage: 120VAC

o DC Amplifier Input: 12 VDC

o Power Consumption: 3W

o Surge Withstand: 6000V

o Operating Temperature: -40° to +140° F (-40° to 60° C)

o Housing Dimensions: 4.0H x 4.9W x 1.1D in. (10.2 x 12.4 x 2.8 cm)

o Weight: 1.7lb (0.8 kg)


* Specifications subject to change without notice Performance Features

* Improve signal strength up to 32 times (15 dB)

* Low noise figure of only 2.5 dB

* Supports Pay-per-view and Video on Demand (VOD) Services


Thanks,
 

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Yes, specs are quite similar. The return loss on the Motorola is listed as 25dB and the PCT lists greater than or equal to 18, which means that the return loss of the PCT could actually be higher than 25, but who knows. It's probably been awhile since that spec sheet was printed.


The power cable just carries D.C. voltage, so even pathetic crimp tools are just fine there.
 

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Discussion Starter · #12 ·
So, do you see any real reason why I shouldn't go with one over the other? If so, then I'm going to head down to fry's and pick up the amp.

Next, I just need to find a good 6-way splitter and I'm done. Well, there are the outlets but I think I can handle that purchase. :-D


Thanks for the info!
 

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The question I'd ask myself is if you really need an amplifier; are you using digital converters or dvrs on ALL of the outlets? If not, then an amp is probably uncalled for. If you are using one box, then use a three way splitter to feed the modem and box, the third port would feed a four way for the rest. Drop amps can cause as many problems as they solve, not the least of which is wrecking the return path.
 

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Discussion Starter · #16 ·
At this point, we plan to have 4 of the 5 outlets hooked up to TVs. 3 of them will have Comcast Digital cable boxes and 1 will have a DVR. The last outlet will be in my office. Eventually, we'll either put another digital cable box or just run the coax into a turner card into one of my computers.

The only things that would stop me from getting a digital cable box are...
  1. Don't need OnDemand or onscreen guides for those TVs
  2. Cost.

I don't think the cost of extra boxes is too much and I suspect the kids will want OnDemand and a guide.


From what I'm gathering, if I use set top boxes/DVRs, an amp is probably required.


I also wondered if I needed an amp but after all those splits, it appeared that dropping approx 14.5 db would need an amp, especially at the higher frequencies.

My plan is to hook up the 6 way splitter and if an amp is needed, I'll hook it up.

6-way splitters seem to range from $5ish to $20ish and the info on them isn't telling me which I should buy. Some say 9db drop but I noticed it usually is in the lower return frequencies so it appears most of the signal is around 11 db drop. I've heard from several people that gold is a gimmick so I'm staying away from those.

I can't seem to find much in a 6-way locally. I saw someone post about a the Steren 1GHz 130dB 6-Way Vertical Splitter which seems reasonably priced and locally obtained but when I went on the Streren web site, they also sold a digital one with slightly better specs and wasn't too much more but I haven't been able to find anyone in the Seattle area that carries this one. I guess I could just order the splitter online since I know I'm going to need one.
 

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If I could be so bold as to say, this is a lot of effort for 5 outputs especially since everything is accessible later. i.e. if Comcast does their job right - giving you +15ish dB at your demarc point with reasonable tilt compensation (they are supposed to provide flat to a "bit more signal" at higher frequencies to compensate for high freq dropoff within your home - this is adjustable at their tap), you have plenty to feed a cable modem tap plus a following 8 way splitter. That is the "standard" - of course it all depends on the dilligence of your Comcast installer - so before you spend money, what the heck - hook it up and try it - it is very likely to work without a lot of fuss.


As an RF engineer myself, I can say that retail specs are a good guideline but marketing folks always seem to have a way of putting a spin on things - better to go with a model or brand that pros say works reliably - most of the stuff on solidsignal.com for instance fits that category - pico/Maacom and others... Admittedly I didn't research your choices, but Frys is a dangerous place - they (almost uniquely) have both the good and the crappy sitting right next to each other on the shelf. (But dang if that isn't my favorite place in the world)...

DF
 

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Justin, thanks for the thread. I'm in the same boat, needing a new splitter. I have Comcast (which I refer to by other names). They also told just me $50 for them to come out and replace it.


In 8 years of dealing with Comcast, I finally could watch all the channels I'm forced to pay for, only because I started pulling my own new cables. It worked great for about 2 weeks then died. Last weekend an "expert" Haitian tech came out and deemed my bedroom cable, attic feed at the splitter, and outside main line all "good", said my new cable was "bad". He kept suggesting that I should fix it myself, but when I asked him what his job was, he finally offered to "fix" my new cable. He only wanted to start hacking ends off, so I asked him to leave. Either his meter just lights up "good" every time or he can't read. Their STB can't get any HBO channels in the bedroom, maybe 1 HD channel, yet he said it was "good", just like every other time they've come out. Some of them like to just change the STB box and run, some like to just hack off/replace ends and run, some don't even show up. Some of my cables can't have ends replaced any more because they've cut them so many times, no cable left.


I removed my keystone jack on the wallpalte and conected directly into my cable, found my attic splitter is bad. I get no signal out of one out port on the 4way, but it's perfect on all channels if I switch my cable to another output.


"If I could be so bold as to say, this is a lot of effort for 5 outputs especially since everything is accessible later. " Yup, it can be a lot of effort to deal with a few jacks when Comcast is envolved. I wish I had a Frys here, all I have is Best Buy, Compusa, and HD/Lowes.
There have been times when I needed a lot of stuff and wanted to "get outa town" so I actually drove 10hrs to Atlanta to shop at Frys and Microcenter for a mini vacation.
 

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Just for clarity, I'm not a Comcast (or any other cableinstaller) - just a CE guy. I'd bet there is a thread somewhere on the "joys" of Comcast.


There are some secret words, though - that I tend to use. The idea is to get a "real" comcast person out and NOT a subcontractor. Yes, yes there are some great subcons out there but so far, when I've had a real Comcast installer I've had good luck. If you tell them you have measured signal strength coming into your demarc point and either that it is low coming into the house or that the tilt is way off - more than 25dB down on the high end, it forces them to send someone who can deal with the neighborhood tap. Maybe don't share the little secret with a lot of people :0


The problem is that they are not responsible for anything beyond the demarc point - you can usually hire them to do in-home wiring for an extra fee, but if they can hook a box or test device up where it comes into your home and it is in spec - you are on your own for how to get it to the TV (again, unless you pay extra) - that is not such a bad thing since that means the cable inside your home is owned by you and can be used for a lot of other things like video distribution...


You should be using RG6 Quad Shield with compression connectors and "good" splitters (Much like Vegas, I you paid under $3 it will bite you)... Search Youtube for coax termination - there are some great closeup videos on compression connectors (HD sells a great setup for not much money)...


And I apologize if my "intro" sounded snotty- not intended


DF
 

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No apology needed sir, I was not hit by any flying snot at all!!


I have no idea how to tell a real Comcast person from a subcontractor here, they all look/think/act alike, and I can't speak their Haitian French Creole language!!



Is the "demarc point" considered the box on the side of my house or where the cable connects into the splitter in the attic? I need to know because I might pull new RG6 throughout the house, existing wire is all 1985 vintage RG59 likely. I already pulled 3 CAT6 to all rooms, so I have some experience. I need at least one more decent 50ft cable here into the computer room so I can try connecting my Comcast RNG150 STB --> Hauppauge HD-PVR --> SageTV server tomorrow night. I only need one working cable for this.


Sorry David, I'm gonna make you cringe, but I didn't have any crimping tools and just bought a 25ft quad shield RG6 copper coated cable at Wally World for my test cable, the connections looked ok, and I gave them a yank test before I shoved the sucker down the the wall. Please dear cable gods, forgive me as I have sinned.
 
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