Designing a Multi Room Video Distribution System For Your DVR
I have too many rooms in my house where we sometimes need to watch TV and not enough satellite receivers to go around. Plus I did not want to pay for services I did not use often. I also have a Replay TV DVR (similar to a TIVO) that I want to be able to watch from any room in the house. I also want to continue to watch off the air HDTV in most rooms.
My budget was $500.00 for the project to provide coverage to a minimum of 4 rooms but up to 6 if possible.
Most of my rooms have an existing single cable connection and a cat-5 connection that is used for phone but could be setup for a network connection.
Being a computer geek and engineer by trade, my first idea was to go all digital. Why not send all my video and audio signals over the network. I quickly came to the conclusion such systems were very immature and expensive. Given I had to work under a $500.00 budget this was not going to work.
During this research I did end up adding a Sling Box to my setup for watching TV over the network and Internet. Without another special box at the TV it requires the use of a PC. This is a great product. Its more for use outside the house since now I can watch my replay while traveling and will discuss more on this later. This was not in my original plans or budget.
Since a full digital system was out of my budget, my next idea was to utilize the existing cable and multiplex several signals on this line. There are many products on the market for this technology typically called modulators. They basically allow you to add extra channels to your cable. A great source for this type of product is Parts Express where I got my parts for this project (they also have a store on amazon and ebay).
Again, I ran into budget problems. My original plan was to have all my receivers in the basement and be able to tune any one. I quickly realized my HDTV satellite receiver would need to stay in the main living room since the technology to modulate HDTV signals over the cable was only available in professional equipment (i.e. way too expensive).
I scaled back my plans to allow my family to watch local channels over the air, one separate satellite receiver, and my Replay TV. All this equipment is analog except for the local HDTV broadcasts over the antenna. My HDTV setup in my living room would also have a dedicated HDTV satellite receiver and our Blue Ray player (plus some other toys like my Apple TV and Replay box).
Based on the above limits I found a great little modulator from parts-express that allows you to add two new TV channels to your cable which allows me to add my DVR and a separate device, right now a second satellite receiver.
As I would find out it was a little more complicated solution to make this work as you'll read in the next section.
Parts Used in Project
The Master Plan (Part 1)
I joke with my wife that this system is called my "Master Plan" and every time I discuss it it grows and grows and since I started this has expanded to include a great new Sony Bravia 46" LCD TV for my living room and a 37" Vizio for the bedroom :-). These pieces were beyond the scope of my initial project and not included in my budget.
The plan was based on the modulator from parts express (see link to right). It looked like it had the answers to all my problems. It had the following features
- 2 A/V inputs via RCA plugs
- 5 Analog Cable outputs with three long range (extra amplification for longer cable runs)
- Support use of remote control receivers that send the I/R signal back through the cable! Very simple wiring.
- Modulate on Channels 14-64 (plenty of channels I figured)
- Less than $100.00
Though the modulator was inexpensive, I need 4 I/R targets that were $47.00 each. So for about $300.00 I thought I had my solution in the bag!
Parts Express is in Ohio (and they have a store on amazon.com - see links to parts used on right) and it only took a few days to get my parts. I brought my equipment into the basement and hooked up my Replay TV and Satellite Receiver to the box. I set the channels to Antenna (UHF) channels 65 and 77 (at first I did not hook up my antenna). I connect my four TV's cable connections to the box. At each TV it was simple to connect the I/R target to the coax cable and run a short jumper to the TV.
It worked! I could watch my Replay TV on channel 65 and my spare Satelitte reciever on channel 77 and use my remote control in any room. I have two Logitech Harmony universal remotes that work great and the original remotes in other rooms.
Now excited to have an all in one solution and still watch local channels (which I don't pay for over DirecTV) I installed the external antenna to the box. Now things started to break down and all my signals were noisy and not watchable.
Ok, so I had my system about 50% working and for awhile I lived without over-the-air TV until my wife suggested we get our new Sony Bravia TV for the living room. I now had this great HDTV and needed my antenna signal.
I spent several days to try several configurations with trying different channels but to no avail, the over the air signals seemed to always overload the modulator. So my next step was to run a separate cable to the living room... Not the ideal solution but it worked for awhile...
The Master Plan (Part 2)
Ok, so I left off with my 70% solution. I had my antenna run to my living room TV on a separate cable and could watch my ReplayTV in any of my 4 rooms. That worked well till we added the Vizio HDTV to the bedroom...
Determined not to run another cable I went back to my research mode to find a workable solution. I went back to Google and started my phase two research. I found most professional systems use separate modulators for each new channel and use external combiners and amplifiers to combine the signals. Looking for other modulator solutions was not an option having already invested $300.00 (I am pretty frugal, just don't ask my wife). I figured I could use the existing two channel modulator and use external multiplexers to combine an antenna signal to each TV run.
My solution was to use a 4-way splitter to split the antenna signal and then combine the antenna signal and my modulator signal through a 2-way splitter/combiner (see block diagram at top of the page). Make sure your combiner has a dc pass through for the modulator side so the I/R signal can pass through! I found mine at Lowe's but can find these online. My first attempt I used some older splitters I had laying around and blocked the I/R signal to the modulator. The 2-way combiners like the Channel Plus 2512 pass dc signals and would work fine. After creating a new distribution panel (see pictures below) and hooking everything up I was excited to have my 100% solution. I hooked everything up but still had problems on my added channels! After some trial and error I found some channels that were marginal but there was still too much interference from the outside world. Looks my antenna works too well. OK, so I am at 85% but not quite there yet.
So I had two problems to overcome, the 1st was to get the my over the air signal to my TV's without overloading the modulator which my new distribution panel solved. The second was to pick modulator channels that would work! Once the analog transition is over this will be easier but right now with both analog and HDTV broadcast, the UHF band is pretty crowded. On top of that the modulator needs to actually have an open channel below and above the selected frequency. That means a block of three frequencies for each modulator channel (or five if they are right next to each other with on channel between them).
In order to find free channels you can do several things. You can scan your TV channels to see which stations are on (need to check both analog and digital and convert digital station to actual UHF channel) or look them up for your area on http://antennaweb.org. This site is really great to help select the right off air antenna for those great HDTV local broadcasts (PBS actually runs 3-4 channels and my local NBC channel has a 24 hr local weather channel). It also lists all the analog and digital stations with the actual channel information. I created an Excel sheet with all the channels (see picture above) to try to find a free block. In my case I had some options in the 30's and 50's but when I went to try my modulator there always seemed to be some distant channels that were causing some interference.
More research found that you can use special filters called Notch Filters. The filters allow you to block the over the air channels and free up space for my modulator. The pieces were starting to come together. I found three bands of notch filters readily available online. Listed all the channels I did not want to block (see yellow rows in table) and chose to block out my analog PBS channel (get 4 channels on the HDTV broadcast so didn't need the analog station which will be gone in June anyway). The model that worked for me was a Channel Plus NF-470 that notched out channels 19-23. This was not available at parts express but did find it at Amazon.com. Another solution was to use a low pass filter and block out the higher channels but as you seen in my spreadsheet the Rochester, NY channels are all over the UHF band and would have lost my digital CBS station. One thing to note, after the HDTV transistion several of the local digital channels will move from their current channels back to their old analog channels. You should be able to find this info on antenna web or you local broadcaster's website.
Allowing for spare channels in between (see table with green rows), I was able to set my ReplayTV to channel 22 and my spare satellite to channel 20. After adding the notch filter to my antenna input and changing my modulator frequencies .... It Worked!
I now have my 100% solution allowing my to watch over the air channels plus my ReplayTV and Satelite on 4 rooms with just one single Coax cable going to each TV. It allows full control on each device from any of the rooms. The additional pieces to complete my systems was about $100.00 ($30.00 for notch filter, $24 combiners (about $6 ea), $10 for 4-way splitter, plus some misc connectors and cables).
Overall I am very happy with my system and met my budget of $500.00, actually finishing at about $400.00. I think the system's features are comparable with systems costing much more. My wife is also happy since the system works smoothly and once I programmed my Harmony remotes its like I have a ReplayTV and Satellite receiver in every room!
I hope you found this article interesting and useful. See some of my project pictures below.