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Tricks to unraveling the braided shield?


Coytee

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I've got some Canare wire, http://www.canare.com/ProductItemDisplay.aspx?productItemID=53

It has the braided shield on the outside (something that makes me want to buy more Mogami next time since it has a wrapped shield)

Anyways... any tricks on how to un-braid this into strands?

Compared to the Mogami, I almost regret buying this stuff, specifically because of the braided shield!!

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I always used a hand scribe, which is a machinist's tool used for marking metal. The best ones have a removable tip that reverses and stores in the handle. It's just the right size to slip between the strands and allow you to pull them apart without breaking wires. Still a job that takes time. Pushing the shield down away from the end helps decompress and loosen it.

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I've been using the tip of a blade.

What a pain.

Ok, let me ask this...

Any benefit of using the braid as my ground and one pair as the hot (leaving the other pair unattached)

Or, should I use blue/hot, white ground leaving the braid unattached

Or, should I use blue/hot, white/ground, attaching the white to the braid so both (white and braid) are grounded on both ends

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The braiding is woven just like a Chinese Finger Grip. After stripping the outer sheathing back the required length (Longer is better), use a pick like above or a deburring tool. Something that has a point but not sharp. Close to where you trimmed the outer sheathing, make a hole by pulling the braiding to either side of the wires it surrounds. Keep doing this uintil the "hole" is large enough to take the tool and slid it through betwen the braiding and the wires and work the wires out through this hole. After they are seperated, just straighten the braiding back out and you are good to go. Very quick and it maintains the braiding to the end of the cut. This is one of the first things you learn when working with Coax. I will post a picture in a bit.....

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I would have never thought about pulling it through a hole, very clever!

I still have an issue if I do it that way (and use the braid for the ground) as the braid will then be too thick to pull through the tiny eyelet of the Neutrik Profi. I would need to cut an estimated 75% of the bulk away to get the wire small enough to feed through the hole.

Perhaps I'm better off using the other pair of wires in there and leaving the braid unattached on both ends? (going into an unbalanced RCA wire)

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Richard,

As a minimum, the braid needs to be grounded on the source end, or it will have a "Slight" affect on the signal. The ungrounded braid will creat a field, if not grounded. It is perfectly OK to leave it unattached on the "Receiving" end. You can reduce the number of starands to make the connection as it is only a shield for the other conductors. I am sure there will be some argument to this...and that is OK.....

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Don't know about audio but with RF (RG-58) if the strands are not perfectly placed around the ground part of the jack you

will get humpy-dumpties all over the place when you put a sweep generator on it with a resistive load.

Humpty-Dumpties---------------peaks and dips and holes over the entire rated frequency range.

JJK

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The wavelengths at 20kHz are long enough that it's not possible to have any phase shift given the typical length of cable - that means no squiggles in the frequency response. Also, it's not uncommon to see HF loss from the cable capacitance.

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Terminate the amplifier input with a low value resistor and any roll-off from capacitance will become moot.

I use 2.2K, most preamps can drive that with ease.

This will also reduce 1/F noise on long cable runs, as much as 10dB.

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Coytee,

What are you wiring? Unbalanced equipment? If so you should always use the shield for the ground connection, otherwise why call it a shield? Whether you also use the white conductors is a try it both ways and see. Adding the white conductors will lower the resistance of the ground connection (good) but also increase the capacitance the signal on the blue conductors see to ground (bad).How long are the wire runs? Remember both resistance and capacitance go up the longer the wire runs.

babadono

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"Wow!, 2.2K is a lot IMHO."

For many tube preamps it might be, for solid state it shouldn't be an issue.

Most SS will drive 600Ω, but they sound better into 2,2K (determined by ear for improvements in noise and bandwidth vs loss of dymanics, I have driven in excess of 100' unbalanced).

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What are you wiring? Unbalanced equipment? If so you should always use the shield for the ground connection, otherwise why call it a shield? Whether you also use the white conductors is a try it both ways and see. Adding the white conductors will lower the resistance of the ground connection (good) but also increase the capacitance the signal on the blue conductors see to ground (bad).How long are the wire runs? Remember both resistance and capacitance go up the longer the wire runs.

These will be about 2' in length, sole intended purpose will be to put toys into the tape loop of my preamp (preamp currently in use is a Peach)

This way I can play around and put my subharmonic synthesizer (and/or 3bx) into the system for kicks & grins when I get the two subs & see if anything outrageous happens.

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I've been using the tip of a blade.

What a pain.

Ok, let me ask this...

Any benefit of using the braid as my ground and one pair as the hot (leaving the other pair unattached)

Or, should I use blue/hot, white ground leaving the braid unattached

Or, should I use blue/hot, white/ground, attaching the white to the braid so both (white and braid) are grounded on both ends

Don't use the shield (braid) as a ground. Use your internal wires for ground and signal. There's no reason why you have to use all of them but using extra conductors in parallel can decrease internal resistance. The shield should be connected to the shell ground at either end, but if you experience hum, you can eliminate ground loops by disconnecting the shield at one end. With balanced line connections, it's critical to use twisted pair internal conductors for the signal. Some balanced cables have a separate ground wire and some use the shield, but using the wrong cable with balanced connections can destroy their ability to reject noise.

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