Question about terminating UTP with Baluns

[lbtech 0]

I am using some passive baluns for a short cable run where cat5 has already been installed.

The baluns I have use a BNC conector on one end and two terminal screws on the other - labled with a + (plus sign) and - (minus sign).

 

The diagram included with the baluns show only one pair of wires being used from the cat5 cable.

 

My question is, for people here that have run cat5 and baluns for video (no power), do you strip and terminate the cat5 using all 4 pairs? (running 4 wires to one terminal and 4 wires to the other terminal) or just one pair? (one wire to one terminal and one wire to the other terminal)

 

The run is only 50' or less and the cameras are powered locally.

[securitymonster 0]

Just install as the instructions say, using one wire per terminal. Just make sure you hook up both ends the same way!

[lbtech 0]

Thought I would pass this along -

 

I tested the baluns using a single wire to each lead like the directions show.

(Brown/white to the positive and Brown to the negative)

This worked great.

 

Then I tested by running two wires to one terminal and two wires to the other terminal.

(Brown/white and Brown to the positive terminal; Orange/white and Orange to the negative)

This seemed to work great too.

 

The theory was that by having more copper, you should have gotten a better signal.

 

However I saved a still image from each of the configurations and compared them afterward.

 

Surprisingly - the single wire connections showed a brighter picture.

 

I ran this test a few times and double checked the connections. Every time, the signal was better on the single cable.

As a side test, I captured an image using a pre-molded coax cable of the same length. The image was indistinguishable from the single wire configuration.

 

My speculation is that the doubled up copper pairs are creating some kind of interference and a loss of quality is being seen.

 

In hindsight, I probably should have tried mixing the wire pairs to see if that would make a difference, but I dont really have the time.

(Brown/white + Orange/white to one terminal and Brown + Orange to the other terminal)

Maybe another time.

[rory 0]

yeah they tell you only use 1 pair for twisted pair transmitters/Baluns or you can have issues.

[Doug 0]

Baluns are designed to be used with a single twisted pair, doubling up or using split pairs will cause problems. The longer the wire, the more acute the problems will become.

 

Doug

 

 

Thought I would pass this along -

 

I tested the baluns using a single wire to each lead like the directions show.

(Brown/white to the positive and Brown to the negative)

This worked great.

 

Then I tested by running two wires to one terminal and two wires to the other terminal.

(Brown/white and Brown to the positive terminal; Orange/white and Orange to the negative)

This seemed to work great too.

 

The theory was that by having more copper, you should have gotten a better signal.

 

However I saved a still image from each of the configurations and compared them afterward.

 

Surprisingly - the single wire connections showed a brighter picture.

 

I ran this test a few times and double checked the connections. Every time, the signal was better on the single cable.

As a side test, I captured an image using a pre-molded coax cable of the same length. The image was indistinguishable from the single wire configuration.

 

My speculation is that the doubled up copper pairs are creating some kind of interference and a loss of quality is being seen.

 

In hindsight, I probably should have tried mixing the wire pairs to see if that would make a difference, but I dont really have the time.

(Brown/white + Orange/white to one terminal and Brown + Orange to the other terminal)

Maybe another time.