Using shielded wires for input and output

[yeeshkul]

It just time for me to start using shielded wires to suppress one of the factors that may possibly cause oscillations   

As i have never used this before i would like to ask you how exactly to connect the shield to the ground.

Lets say i have a pair of wire (in/out) coming from a circuit board to 3PDT switch and another pair from the switch to jacks:
CIRCUIT => IN/OUT wire => 3PDT => IN/OUT wire => JACKS

Shall i ground the wires coming from the board on the board and the other ones on jacks? Shall i connect the grounded shields of the both pairs?

thank you

[plankspank]

You connect only one side of the shield to ground (i.e. at the input jack) and leave the other side to the circuit input floating. I normally just use shielded wire on the input side only.

[yeeshkul]

thanks man, are you shielding the both parts - before and after the DPDT switch (input)? I mean in case the input wire goes first from input jack to DPDT and then to circuit ...

[rpjones]

http://www.mrdwab.com/john/Shieldedwire.html

[yeeshkul]

brilliant! that's what i needed

[railhead]

Okay, let me make sure I'm getting this straight:

1. Strip the outer insulation off both ends (duh).

2. Unbraid both ends of the braided ground, twisting them together, and bending them along the length of the wire.

3. Solder a bit of wire to the braid at one end, for use as the ground. Shrink wrap/tape the connection.

4. Heat shrink/tape the other end of the wire so that the bent back braid won't come into contact with anything.

5. Connect the "new" ground to the jack ground, switch ground, or pot ground.


If that's right, here are my questions:

1. Why don't you just snip off the braids at the one end, and just shrink that portion of insulation?

2. Does it matter where the ground is connected? For input, it seems it would be easier to connect the ground to the jack and then hook to the switch as normal -- but does it matter? Could just tap the ground tot he switch ground and accomplish the same thing?

[yeeshkul]

"Unbraid both ends of the braided ground, ..." i am not sure if i understand here - just bend all the shielding around the edge.

"Does it matter where the ground is connected?" .. there is just one ground

[rhdwave]

Sorry to bring up an old thread, but i have the same question as i think railhead asked re: the shield at on of the ends:

Instead of shrink wrapping the shield at the one end where you're not connecting it to avoid any shorts, is there any disadvantage to just cutting the braided shield off completely on that end and just leaving the hotwire to connect? It seems this will ensure there is no shorts.

[John Lyons]

(In my article) I cut the braided shield off at the end and left the hot wire only.
I usually put srink tubing on it anyway because you still have a small amount of braided wires poking
out that will possibly touch something else and cause a short. If there isn't anything it will touch
nearby them you don't need the shrink tubing. Just a precaution...

John

[rhdwave]

Thanks John! I did the same thing last night...seemed to work just fine.  Thanks again for all the info.

[MartyMart]

For the end that does NOT get connected, I carefully gather the braid together, twist and "tin" it with solder
then bend back against the outside cable jacket, cut it down to maybe 1cm and put heat-shrink over that and
including the start of the other wires, so sealing the whole thing off.
Works well and looks neat.

[yeeshkul]

That's what i do too, bend the braid and fix it by heat-shring  .