Hello I am trying to find some Shielded wire like some builders use in the tone bender mk1's. I found some grey pvc stuff but has foil shielding vs braided so basically grey braided single conductor but i'd take 2 conductor probably 20-22 awg in a grey jacket. Ive searched with no luck. Any sources?
I use the free stuff that used to come with CD players and stereo stuff. It's usually very flexible. Some folks but RG174 I believe.
small bear has it. RG174, 178.
Bought Teflon/Kapton coax from here years ago and still using it when needed, great to work with.
http://www.ebaystores.ca/Johns-Silver-Plated-PTFE-Wire-Shop/Shielded-Wire-Coax-/_i.html?_fsub=3966787&_sid=155009&_trksid=p4634.c0.m322
dave
I thought he was talking about 2-core screened/shielded cable,
https://www.altronics.com.au/p/w3021-2-core-white-twin-audio-shielded-cable/
(They used to have the grey but it didn't come up on their crappy web pages.)
Two or more with shielding from the same seller as linked earlier, loads of other wires as well.
http://www.ebaystores.ca/Johns-Silver-Plated-PTFE-Wire-Shop/Shielded-Wire-2-or-more-cond-/_i.html?_fsub=3966788&_sid=155009&_trksid=p4634.c0.m322
dave
Quote from: Jasonz on August 10, 2020, 05:43:33 PM...Shielded wire .... Ive searched with no luck....
You might say where you are, and where you have looked. Back in 1990s New Jersey I could buy shielded about anywhere, any thickness. Today here in far-out Maine I might only find stiff TV Coax locally, but can order anything online. But there are places where online ordering is hard.
Twin-core is mike cable, 22ga is thin/cheap mike cable. Go to a band's sound-guy or a sound store, beg a "bad cable". A 25 foot cable which "cuts out" is 20+ short lengths for in-pedal wiring. (Unless there is a nail-wound in the cable, the bad part is always at the ends.)
Thanks for the suggestions. I think blackie hit it with the RCA cables and mic cable would make a good 2 conductor. The coax works but usually not very flexible and i'm trying to somewhat replicate the old stuff in the mk1.
ive been using the rca cables too, no probs.....and have loads of them lying around... 8)
Inside an enclosure, tightly twisted pair can be as good as screening. Works to keep tube heater hum out and your telephone and CAT5 wires totally rely on twist. Hand drill your own twisted (power drill is only for the brave).
And yes, if you have 3 wires for a pot and you're worried they might pick up feedback, you can twist all 3 together and get some protection and a neater look.
So I need to, or have been advised to ( by Jimi ) to use shielded wire from the switch.....
Looked at some coax, have miles of that, then after reading this topic RCA is mentioned.
Have many of those cables for my stereo ( not compatible with earbuds, lol)
Question:
The rca cable has an insulated center wire surrounded with strands of fine wire, I assume is ground.
Should these ground wires be connected to ground on both ends ?
Or is it "shielded" by just having those fine outer wires wrapped around it ?
Thanks in advance
Connect the shield (surrounding the center conductor) to a ground at one end, but clip it off and leave it unterminated at the other end. Center conductor connects at both ends as usual.
https://www.emcstandards.co.uk/cable-shield-grounded-at-one-end-only (https://www.emcstandards.co.uk/cable-shield-grounded-at-one-end-only)
https://incompliancemag.com/article/things-you-may-not-have-heard-about-shielding/ (https://incompliancemag.com/article/things-you-may-not-have-heard-about-shielding/)
(The Effect of Shield Termination near the end of article..)
https://www.nutsvolts.com/magazine/article/November2016_HamsWirelessWorkbench-Shielding-Cables (https://www.nutsvolts.com/magazine/article/November2016_HamsWirelessWorkbench-Shielding-Cables)
And, of course, this article...
https://incompliancemag.com/article/things-you-may-not-have-heard-about-shielding/
... concludes with...
QuoteThe decision to terminate or not terminate depends on the application. Unfortunately, there is no rule that applies to all situations, and an experiment is often required to determine the best way to terminate the shield.
Remember this suff ? Flat 2 wire. For use with 75 and 300 ohm antennas.
(https://i.postimg.cc/gnSpS9yV/20221023-080534.jpg) (https://postimg.cc/gnSpS9yV)
300 ohm, that's balanced wire. Transformer will convert that to 75. We used to slide tin foil on it to help bring in the picture.
I think your wire disagrees with its label. The wire is 300r twin, the box says 75r coax.
The twinlead is so strongly optimized for whipping in the wind with 400MHz 300 Ohm signals that it is awkward or crappy for almost anything else. (I have seen 8 inches inside an oscilloscope to carry the push-pull deflection signals to the CRT electrodes..... not really a 300r circuit but not long enough to hurt.)
The other, 75 Ohm coax is NOT good for short audio. Too fat, too stiff, nasty to strip and solder.
Audio box coax-- GoodWill has a bin of RCA-RCA shielded cables, mostly small and limber. Just watch for the inside insulation melting and letting the center touch the shield.
Some of those RCA audio interlinks are pretty cheapie though, quite often a really thick PVC outer jacket, tiny center conductor and very little shielding copper, so a lot of care is needed when stripping these.
I have a roll of RG174 from work, which was going to be thrown away. thin, but good amount of copper, it is just that the jacket and internal isolation material are quite tough.
QuoteI think your wire disagrees with its label. The wire is 300r twin, the box says 75r coax.
Agree, flat antenna cable might have been rolled up and put into that coax sleeve. 25 years ago. I like to keep my wire stash organized.
(https://i.postimg.cc/ygPtM3zv/20221024-081234.jpg) (https://postimg.cc/ygPtM3zv)
Could you wrap any old 24awg wire in copper tape, then heatshrink it, to make a shielded wire?
With a drain wire, yes. Very stiff though
I'm cheap. I use old RCA cables from TVs, home theaters, etc. The ones with left+right+video.