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Using Cat5 Cable for Audio/Video, Security and HDTV Applications

With electronics in the home getting more and more sophisticated, needs for sending audio and video signals over considerable distances of cable throughout the home, are becoming increasingly common.

Common occurrences of this need:

  • Connecting the DVD player, located in a wall cabinet, to the projector mounted to the ceiling in the middle of the room
  • Feeding audio from the computer in the den to the sound system in the great room to allow MP3's from the hard drive to be played while entertaining
  • Connecting that surveillance camera located on the far corner of the house to the DVR in the utility room

Typically, connections of this type involve large, expensive cable that is difficult to run, has distance limitations and has no flexibility for future upgrades.

Until now.

MCM Custom Audio offers a complete line of A/V to Cat5 baluns which allow you to run common audio and video signal formats over compact, inexpensive Cat5 data cable. Composite video, RGB component video, S-video and line level and digital audio can easily be sent over UTP cable distances up to 1000'. In retrofit applications, utilize existing unused pairs of Cat5 data cable already in place. In new construction, take advantage of the smaller size and lower cost of Cat5 cable when distributing signals throughout the structure. Housed in compact ABS enclosures, each balun accepts standard RJ45 male connectors. Completely passive design, these units require no power.

The added beauty of this arrangement is future flexibility in that changes in signal format no longer cabling changes. Simply leave the Cat5 cable intact, and change only the baluns at each end. Take a look at each scenario below to see how using baluns can help you.

Solution 1

Your Home Theater room is quite large, and the components are in a cabinet on the side of the room. Your high definition plasma monitor is mounted to the wall, above the fireplace. The room is on a slab, the ceilings are vaulted and quite high, so the total distance of component video cable needed (to get through walls and across the attic) is 100'.

You will need

(2)MCM Custom Audio Component Video Baluns#50-7722
(1)100' length of preassembled Cat5 Cable#831-1705

What to do

Simply use the included hook-loop fastener to attach one balun to the rear of the plasma display, and plug in the attached red/blue/green cables. Connect the second balun to the DVD player, in the same manner, route the cable and plug it in. It is that simple!

This installation will provide substantial cost savings when compared to 100' of Component Video Cable, with smaller size that will make running the cable much easier.

Solution 2

You would like to install a video camera under the roof overhang in order to see when someone is at the front door. You don't need an expensive security video monitor, you would simply like to see this on the video input of your television.

You will need

(2)MCM Custom Audio Video Baluns#50-7745
(1)100' length of preassembled Cat5 Cable#831-1705
(1)Defender Color day night camera#82-11484
(1)DC power adaptor#82-3950
(1)RCA male to BNC female adaptor#33-510

What to do

  1. Install the #82-11484 camera outside, making sure it is out of direct weather, preferably under the roof overhang.
  2. Connect one #50-7745 balun to the BNC video output of the camera.
  3. Remove the barrel plug from the AC adaptor, leaving approximately 6/u201D of wire attached to the barrel plug. Using a voltmeter, determine which lead is + and which is - on the AC adaptor.
  4. Attach the proper leads to the + and - screws on the camera and plug the barrel plug into the power connection on the camera.
  5. Plug the #831-1705 Cat5 cable assembly into the balun and rout inside the house (likely through the attic) to the destination television.
  6. Select an unused video input on the television and insert the #33-510 RCA to BNC adaptor.
  7. Take the AC adaptor, with its output plug removed, and connect the bare leads to the + and - screws on the second #50-7745 balun. It is critical that the + and - connections on both baluns are correct.
  8. Attach the balun to the female BNC connector on the installed #33-510 RCA to BNC adaptor.
  9. Plug the #831-1705 Cat5 cable assembly into the balun.
  10. Plug the AC adaptor into an AC outlet.
  11. You are now ready to view the outdoor camera from the video input on the television.

Solution 3

You have hundreds of music tracks on your computer in the den, and you would like to be able to play them on a sound system that is nowhere near your den. Running new cable between the two areas is not practical.

You will need

(2)MCM Keystone Mount Baluns (red audio)#50-7760
(2)MCM Keystone Mount Baluns (white audio)#50-7761
(2)MCM Adaptiplate Keystone Mount RJ11 Jack#50-10795
(2)MCM Adaptiplate Keystone 3-port Decora Insert#50-10160
(2)MCM Adaptiplate Decora Covers#50-10100
(1)Stellar Labs 6' Audio Patch Cable#24-9512
(1)Stellar Labs 12' Audio Patch Cable#24-9493

This solution will work only if there is telephone jacks located in each area, near the sound system and computer.

Residences built within the last 30 years are typically pre-wired for up to four telephone lines. If you have only one telephone line, you likely have three wire pairs that are unused. Remove the telephone jack from the wall in one room and determine if this is the case. Even if you have an older home with twisted pair wire that does not meet Cat5 specs, these baluns will work OK as they are effective with Cat3 rated UTP wire up to 200'.

Note: It is critical that these unused pairs are not connected to any telephone equipment or to a telephone line. It is also critical that unused pairs are connected together. In daisy chain installations, this is already done. In home run installations, you will need to go to the central point to make sure unused pairs are connected to each other.

What to do

  1. Locate the first telephone jack to be used. Remove the jack from the wall and note which pair it is connected to. Disconnect this jack and connect the new #50-10795 keystone mount jack. Plug in a telephone to this jack to make sure it functions properly.
  2. Now select a second unused pair within the wall. Connect the #50-7760 red keystone mount audio balun to this pair. Be sure to note which wire is connected to the tip and ring connections on this balun.
  3. Select a third unused pair within the wall. Connect the #50-7761 white keystone mount audio balun to this pair. Again, be sure to note which wire is connected to the tip and ring connections on this balun. When connecting the baluns at the other jack location, it is important that the same polarity is used.
  4. Snap the telephone jack and two audio baluns into the #50-10160 three port decora insert. Reinstall the decora insert into the wall in place of the original telephone jack, and then install the #50-10100 decora cover.
  5. Repeat these steps at the location of the second telephone jack.
  6. You now have L/R audio jacks in each room that are connected.
  7. Use the Stellar Labs audio cables to connect to the baluns and you are ready to go.