I'm trying to organize the antenna feeds at home. There are two separate antenna -- TV + FM. And, two CATV feeds (one acting as a spare). These will, in some combination, feed up to ~15 drops throughout the house through a set of splitters.
Of course, "what goes where" can change over time. So, I want to be able to "rewire"/replace the splitters as the need arises.
My current plans are to terminate the source feeds and one end of *each* drop in male F-connectors at a "patch panel" (of sorts) consisting of double threaded (female) F-connectors.
Then, connect the sources to splitters (i.e. for each source) using male-male "patch cords" and the splitters to the drops with similar patch cables.
It is unlikely that every drop will ever be driven from any single splitter. Worst case would probably be an 8-way. In practice, probably 3 or 4 -ways.
I'm using RG6 and the longest drop is probably ~70 feet. So, I figure roughly 5dB in the cable and ~10-12dB in the (8-way) splitter(s).
I figure I can insert a small wideband, in-line amplifier ahead of each splitter to compensate. And, a power injector
*immediately* downstream of that (no mains power available nearby).
Schematically (fixed width font), something like this:
_ V (antenna, CATV, etc) | | |
+-> >< >AMP< >INJ< >< >-S | : : : P |
--> >< >-L-< >< >-T
where "" are patch cords terminated in male connections and ">
This sounds like you need to designate a 'wiring closet' area where all the signals terminate. Don't put it near the electric power panel, or the furnace, or you'll have lots of routing problems.
...
The signal levels drop in the cable, of course, but SO DOES THE NOISE. So, you might easily need no amplification for this, and (depending on how your cable service works) simple amplifiers might bollix up the backchannel communications. In some cases, a trap (for nearby transmitters) or attenuator might be useful; get an attenuator, and if you can set it at -10dB and still get good signal, there's no need for that 10dB line amplifier...
Assuming the splitters don't have resistors in them, which very many types do, e.g. the Wilkinson hybrid. Your average TV antenna has an effective antenna temperature of something like 800 kelvins at 100 MHz, rising steeply at lower frequency. (See e.g.
formatting link
.)
So a front end with a noise figure of 10*log(1+800/300) ~ 5.6 dB will start to dominate the noise budget at 100 MHz. I sort of doubt that your average TV is going to have a front end whose noise is much less than this, so signal attenuation starts hurting you right away. The resistors will make this worse fairly fast.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
160 North State Road #203
Briarcliff Manor NY 10510
845-480-2058
hobbs at electrooptical dot net
http://electrooptical.net
No (*thankfully*!). There are actually ~twice that number of drops. Most rooms have more than one -- to allow kit to be relocated ("Let's put the TV in *this* corner! No, on second thought, how about *that* corner??") without cables trapsing along floorboards, etc.
Also, the four feeds effectively have four *drops* located in the equipment closet. I've been trying to move all media to distribution "over IP" (instead of wired antennae, cable, etc.). But, it will be a while before I hook up the DTV/CATV decoders (havent even *started* the design of the video clients until I sort out performance issues for the *audio* clients)
However, I haveno intention of leaving all that kit for any "future owner" of the house so I want, as a fallback, to just be able to point to "traditional" cable drops ("You can hook up your TV/HiFi here. Or here. Or...")
Not a big problem. So far I've spent $0 (had 1,000 ft of RG6 plus a collection of splitters, F connectors, etc.). Biggest issue is the "mechanical" one -- figuring out what needs to be mounted and how to arrange it in a serviceable manner.
Same here, but I see that differently. It hones my prototyping skills and I chalk it up as "continuing education". Besides, when I met my girlfriend who is now my wife she was always quite impressed that I could fix or build just about anything she threw at me. Got to keep up that reputation :-)
Yet an other reason is that when one sits on the keister in front of the computation machine all day long that will, over the years, foster a certain "rotundness" which ain't healthy.
Given my heart history, I try to walk 2-3 miles per day. ...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
THat's the problem. No attics or basements, here. And, the house floorplan is very "open" so few places to hide things. The *best* place for a wiring closet I have set aside for all of the networking/automation stuff alongside the servers. Unfortunately, making wiring accessible (for change) uses up a lot of space! E.g., my current network cabling design puts the cables in a
*drawer* so I only use ~3 inches of vertical space to support the full panel (48 points).
Since (aside from inline amplifiers) the antenna/CATV wiring doesn't need easy access and can tolerate harsher envirnments, I've tucked this in the "ceiling" (i.e., flat roof) where I can get to it if I *really* need to (e.g., to rewire which feeds go to which drops) -- but don't *expect* to need access.
I have four drops (for the four feeds) running to the equipment closet. One of the feeds is a spare (in case a problem develops with the CATV feed) and the corresponding *drop* is likewise.
E.g., assuming no wire failures, I can run the cable feed directly to the wiring closet (e.g., for a cable modem) and then *back* to the main wiring hub (on the spare drop).
Of course, that then reduces my ability to cope with future wire problems/needs :>
Easy fix: A (removable) bridge in the fist wall box and running a cable over to the next. And the third if there is one.
Yeah, keep it simple. That's what I tried to do. I ran four cables to each location which was overkill but not expensive. Just harder to pull. The phone runs are not used and might never be. The LAN is, because WLAN is iffy and slow. Then two coaxes each, one for back-feeding.
Hint: Leave a few feet of service loop for each. In case you screw up an F-connection later. Cheap insurance.
Ah, forget it. Even if you rip all this out when moving, afterwards it'll sit in the new garage and collect dust. BT. Still have the PBX from a previous residence. Guess where it lives? Right, in a garage cabinet.
Yeah, but to do it properly that's not going to suffice. You'll need buffer amps, splitters, filters and other additional hardware. Which either costs money or time if you roll your own.
That ChannelPlus unit has been in a garage hot-water-tank/softener closet for 15 years.... no A/C. ...Jim Thompson
--
| James E.Thompson, CTO | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Modern digital cable plants top out at somewhere between 850MHz and 1GHz. Most are at 850MHz. The tricky part is the cable is bi-directional; the set-tops transmit signals back to the headend for interactive services (video on demand, for example).
If you're with cable company such as Comcast, the return path is below
100MHz, maybe even below 54MHz (my memory is fuzzy). Cable modems use this same path for the upstream data.
If you're on FiOS, a technology called MoCA is used (Google it). MoCA essentially creates an Ethernet type LAN (or LANs) above 1GHz (1.1GHz isn't unusual, but it does change). It is used for communication between the set top boxes, the router, and the ONT. MoCA is able to pass through splitters - it can go in one "out" port and come out all the other ports. Of course, there is significant loss when it goes through splitters, but it is designed to work with typical home coax networks.
So, if you want the return path to work, make sure you use the right splitters and amplifiers that match your service provider. For cable companies, make sure any amps have a low loss upstream path. For FiOS, be careful with splitter and amp selection, as they shouldn't block the high frequency MoCA signals.
If you spend some time with Google and Wikipedia, you should be able to get a good idea of the frequencies and technologies in use by your particular service provider.
You're looking at the problem backwards. Use the TV as furniture anchors. Tell her to plan where the TVs go and that will anchor the rest of the furniture; no more rearranging parties ever few months. ;-)
"Yeah, the sofa would look good over there, but then we couldn't see the TeeVee. Besides, the big game is on. Get me a beer."
When I was framing the walls in the kitchen, I thought of that approach. But, figured it didn't buy me much in terms of savings. On the downside, it would have been "puzzling" for a future homeowner to sort out. And, would have made it difficult to cram all the cables in each box (even if you restrict yourself to daisy-chaining -- one "in", one "out") as I have network and phone drops in every box as well as "bits of electronics" in many cases.
As i is, I opted for *very* deep boxes and selected ones with built-in cable clamps (instead of the traditional ones) as that allows the "clamping screw" to be accessed from inside the box (contrast this with traditional clamps that locate the screws exterior to the box -- inaccessible for "new work" boxes once the walls are in place!). So, I could "push back" the extra service lop cable *outside* the box (into the wall cavity) instead of having to leave it coiled up inside the box (RG6 has a reasonably large bend radius).
Wire is cheap. If you are at a point where you *can* pull, the cost (effort) to pull several is nothing compared to the cost of having to pull a *replacement* (or additional) later!
I ran CAT3 for the phones - mainly because that was cheaper (free!) than buying a spool of "quad". But, that's there "for future owners" as the phones here are moving to VoIP -- like everything else!
[The goal here is to get rid of all the "kit" lying around the house as well as centralize its maintenance. Let the house know what you want -- on demand or algorithmically -- and then let *it* get it to you, wherever you might be.]
Yup. See above. I was even considerate of *how* each cable entered each Jbox to try to anticipate kinks, twists, etc.
I trashed the PBX ears ago. :> But, the multimedia and automation aspects of the system are reusable "as is" (forget the "wire" and other infrastructure aspects -- they're disposable). You wouldn't discard your hifi/tv/{cd,dvd collection} just because your address changed? :>
So far, it looks like the buffer amps are the missing ingredient. The bigger issue is making sure it doesn't have to be done over (or -- GASP -- *relocated*!)
That's why I took the time to add the terminators, etc. (though I much prefer your solution! more "resilient")
Not an option. The only available space is set aside for the media server and networking kit. I've already stolen damn near every conceivable "nook" for other things. E.g., the telco wiring sits in the furnace "closet"; automation system in a false ceiling in one of the closets; access points are currently fighting for spots in the skylight wells (I had wanted to put them *behind* these wells -- in the ceiling -- but fear the radios wouldn't tolerate the heat).
The annoying thing s the "wasted"volume in some of the HVAC soffits that can't be exploited (without adding a very VISIBLE "access panel").
We don't have cable service (there's nothing on TV that is worth the time that could be spent on something more interesting/productive). My efforts there are mainly intended as a courtesy to any future homeowner (or, if I ever become an old couch-potato-fart! :> )
Agreed. We have an *almost* perfect line-of-site to the towers atop the (nearby) mountain. But, a neighbor's tree wreaks havoc with things in high winds, rain, etc. (I could *probably* work around this -- just barely -- if I wanted to locate the antenna on the rooftop at the other end of the house... but, that makes it more visible, harder to cable, more prone to lightning, etc.)
Huh? You mean it didn't end as predicted LAST year??
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.