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Belden 8451/9451-like STP wire that fits in an RJ11/RJ45?

S

spinjector

Does anyone know of a wire brand & model number with a single shielded pair with wires that fit all the way into an RJ11 or RJ45 plug?

The individual wires of Belden 8451 & 9451 are too thick to slide into the "crimp zone" of RJ11 & RJ45 connectors. They fit if the insulation is stripped off, but then you run the risk of cross-contact.

I thought perhaps it might be possible to dip them in that "liquid electrical tape" from Home Despot, but that's too much complication. It's just be easier & simpler to have the right wire.

...and now that I've typed all this, I've just thought to also ask if anyone's ever seen shielded CAT5 or CAT6 cable?
 
You can get shielded CAT-5 cable (probably CAT-6 too) from a variety of suppliers. There are also shielded RJ-45 connectors.
 
Does it need to be shielded? If you have a balance audio circuit (neither side grounded), Gepco 5100 (single pair) or 5200 (two pair) is a twisted cat-5 style cable that's great for audio (both analog and AES), that fits great in to a RJ-45 connector. We're currently building a network owned radio facility that uses almost nothing but that, and Cat-5/6 4-pair and 25-pair trunk. To prevent crosstalk, all circuits have to be balance; OK, you could probably get away with SHORT runs of unbalanced. For data circuits, RS-232 serial is unbalanced and needs a ground circuit, whereas RS-485 is balanced and can be run on a single pair such as the 5100.
 
It's for RS-485, so I reasonably certain it needs a shield; I've never seen RS-485 without one.

And it has to be a six-pin RJ11 connector. It's for the remote port on an Intraplex.
 
RS-485 is a balanced circuit and does not need a ground or shield to operate.
 
Hmmm I suppose you're correct. Ethernet is twisted pair, and those get high speeds over long distances without a shield.

All the documentation I've read on sites such as B & B Electronics babble about the importance of a shield, but perhaps that's to allow for RS-232 and RS-422 as well, which are unbalanced.

Also something I had in my head but didn't explain is 9451 is more durable that plain unjacketed blue & white telecom interconnect wire, which is something else I was looking for.
 
I second ORG. I am a Belden guy but the Gepco 5100 is the cat's meow. I was introduced to it on a turnkey install a few years ago. The installer used it as cross connect wire on a wall full of Krone blocks. Made for a very neat install...

Since then I have used it in a number of places for line level audio.

I have also used it as single pair phone cable using EZ RJ-11 connectors. Those EZ RJ connectors are the real deal. A little pricey but worth it as it saves time and waste.

Test123
 
At the encouragement of Steve Lampin, of Belden fame, I've used CAT-5 (with no shield) for balanced line-level audio for years. It works fine. I've had no problems with hum, cross-talk, or RF interference. In fact, leaving the shield out of the equation gets rid of a lot of ground loops as well. For fixed permanent wiring, it is very versatile.
 
Regarding the post about Steve Lampen (Belden Cable), I too saw him at a SBE meeting where he was telling us to use Cat5e for studio builds (low capacitance cable, perfect for balanced audio cable)

Those EZ RJ series connectors are great: make for a fast install and confirms proper pair sequence. If you haven't used them, I highly recommend that you try them.

http://www.platinumtools.com/products/100003.php?cat=5
 
Could someone please post a link to the Gepco 5100 or 5200? I'm on the site but can't find either :(( I must be searching wrong, but still no cigar.... Thanks!
 
I have not found it online either. The label on the spool says P/N: GEP-5100-0 Single Pair Cat5e Black.

You can call them at 800-966-0069 according to the label. Or call your favorite Gepco dealer. I think SCMS is a dealer. Mine spool came from Ram Systems.

I need some more. I may call around next week. I would like some of the two pair.

t123
 
I have had good success running balanced line level audio on Cat-3 phone cable. In the sports remote business it is not uncommon to have to use phone pairs to get audio around.

I have found a fair number of PA guys that have a hard time believing that audio will pass on anything but 'audio' cable.

My first trip to the Las Vegas Motor Speedway my assistant and I found that the PA booth was 2 booths away from the radio booth but there were mouse holes so it was no problem pulling a cable. When we were setting up the PA guy wasn't there. We pulled a regular old piece of two pair Cat-3 IW from the radio booth to the PA booth (about 40'), put two RJ-11 biscuits on both ends and plugged in XLR to modular adapters labeled TO PA and FROM PA on them and left. Next day we checked with the PA guy to see if he had hooked us up. He refused to saying there was no way audio would pass on that cable. We gave up arguing with him and pulled the cable back to the booth next door (TV Booth) put the biscuits back on and ran a couple of mic cables through the hole. At the end of the show my assistant had to go ask him how our feed sounded. He said great!

Ran into a similar situation at the Georgia Dome a number of years ago. We found out during the pre-game show the President was going to speak on the video board and the producer wanted to carry it. There is no PA feed in the visiting radio booth at the Dome. The only cable we had long enough was silver satin phone cable. I ran it down the hall to the video board control room, put a RJ-11 to XLR adapter on it and asked the PA guy where I could plug it in...He said 'that's a phone cable'. I said yep. He said you can't send audio over a phone cable. I asked him if he had ever talked on the phone? He said yes. I said isn't that audio? He thought a minute...Then he agreed to put the feed on the cable but told me I could not blame him when it wouldn't work. It did work fine.

t123
 
test123 said:
I have had good success running balanced line level audio on Cat-3 phone cable. In the sports remote business it is not uncommon to have to use phone pairs to get audio around.
Click to expand...

Indeed, I have seen many studio installations using the old 25 pair cable from an abandoned 1A2 key telephone system.
 
I would like amend my post on the 5th to say those PA guys were good guys. I have worked with a number of PA guys over the years that were very helpful but were not used to dealing with issues that broadcast engineers come across when outside the studio.

It is always a good idea to use sound engineering practices when possible. That includes using the proper cable. Sometimes situations dictate that you use cable that you normally would not use. Can't blame a PA guy for wanting to use sound engineering practices all the time and not having the knowledge that cable other than 'audio' cable can work just fine in certain situations...

I tried to delete my post the day after I posted it. I guess you can only edit a post within a certain period of time.

In other news...I contacted SCMS about the Gepco GEP-5100. They do sell it. I also asked for a sample of GEP-5200 and the 4 pair GEP-5500. They told me Gepco does not provide samples and apparently Gepco doesn't actually make GEP-5100.

I never actually looked at the printing on the cable but the company that apparently makes it is printed right on there. Quabbin Wire and Cable in Ware, MA makes it.

http://www.quabbin.com/index.html

Test123
 
So Quabbin cable, not Gepco, actually makes GEP-5100? I see how that could be confusing given the "Gep" in the title. I'll have to give that cable a look. Thanks for the additional info.

Also, for what it's worth, I did not interpret your post as being critical of PA guys.
 
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