Really?
Most cables I see in the Belden or Cannon CDT line cards at best are Polyethylene and I don't think the reason they use it is for it's lower dielectric losses vs. PVC.
I think the reason they use that stuff is for Plenum halogen ratings no?
Can you please provide me a link to a major manufactured industrial cable that can be ordered in a large put that has Teflon as it's insulator?
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Perhaps Richard Marsh can put in his opinion about Teflon in large labs, like LLL in Livermore, where he worked for decades.
My input comes from LBL, Berkeley. Trust me they have used lots of Teflon.
Teflon, however, does NOT necessarily make a great cable. I once ordered some Teflon cable for a laser control system that was recommended to me by an associate at LBL.
The wire was pure white, coax, small, flexible, reasonably priced, and had a 5,000V breakdown (this was important in my application).
I tried to make audio cables from it, just to try, and they wound up sounding LOUSY! I don't charge the Teflon as the problem, but we sure were disappointed. I decided, instead to use it for instrumentation hookup and some of this cable resides on my lab bench today for this use.
My input comes from LBL, Berkeley. Trust me they have used lots of Teflon.
Teflon, however, does NOT necessarily make a great cable. I once ordered some Teflon cable for a laser control system that was recommended to me by an associate at LBL.
The wire was pure white, coax, small, flexible, reasonably priced, and had a 5,000V breakdown (this was important in my application).
I tried to make audio cables from it, just to try, and they wound up sounding LOUSY! I don't charge the Teflon as the problem, but we sure were disappointed. I decided, instead to use it for instrumentation hookup and some of this cable resides on my lab bench today for this use.
Mechanical creep, compression related. If for example, you have a twisted pair of teflon wires, and put a weight on them, eventually the wire to wire crossover will short. If you take a single conductor and pull it around a metal corner in a chassis, the corner may eventually break through to the conductor.
If somebody made a line cord using teflon insulated wires and I found out, , I would beat them silly. I can do that through the web, you know...I have an app for it..
jn
Caused by quarter-wave transformers turning high impedance into low impedance. Standard trick of the RF fraternity.
There is a standard formula (I forget if it has a name) for calculating the input impedance of a line of a given length terminated in a given impedance. You could use a spreadsheet, provided it can handle complex numbers. This will show the behaviour you are seeing.
Is this due to cable geometry and the fact the return conductor has different impedance that the conductor?
What would be the best geometry to use for shielding less UTP?
Teflon coated wires are great for higher temperatures or for some specialized coax where the dielectric constant is appropriate or that might see high temps. Not much other use beyond that. Bob Pease (I think it was he) pointed out some pitfalls beyond the poor mechanical properties related to solder wicking and consequent stranded wire failure near joints.
I've had that exact problem for two reasons. All the mechanical flex of the wire will occur right where the solder wicking stopped, and this is a very bad thing if the insulation is stiff.
The other issue I've had is the flux wicking up in the stranded wire, and it cannot be adequately cleaned out afterwards.
jn
Mechanical properties combined with wettability of silver (which is needed for PTFE coextrusion). See jn's post above.
huh?
Hit it with an iron and the flux should turn to gasses/smoke out of the cable. Modern fluxes are not as corrosive as older ones so I don't think it's much of a concern even if some is at the insulator or past it under the jacket. I actually purposely strip long so I have a good 3 mil of bare conductor between the strands and the insulator due to this and I then use shrink tubing to where it terminates because this did occur to me.
For a bunch of insider famous "guru" EE designers you guys sure have a bunch of strange stuff to say that's rather unorthodox IMHO.
Especially John there...
I'm starting to wonder if this isn't a BS circle and some kinda inside circle jerk joke to weed out the morons or something.
I've always thought this when Boutique AV sellers offer expensive cables and magic power cords or they offer a piece that's BOM x 10+.
I can't help but find it insulting and I'm not an EE or work in the industry even.
I still wonder this from time to time when speaking to highly respected audio EE designers and in looking at their wares that all to often include SNAKE OIL items on their line cards.
I seriously wonder often in this hobby, "Are you f'ing with me?", "Your kidding right?"
RIGHT!?!
PS especially when I read the reviews of boutique gear!
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Oh you're talking silver conductors. I can see that.
I also know that any teflon conductors I've looked at the mechanical sinch with the strands isn't as good as other materials like PE, PVC etc.
I now understand I think what you guys are saying and the point being?
Don't fart around with expensive fancy teflon tubes and silver strands like an idiot?
LOL
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Now how would that be useful?
How would pyroelectric charge separation that will added to existing contact electrification be useful when it may oppose the existing contact polarity?
That would be detrimental not useful no?
PS I'm going to start using the Socratic Method and see what happens... LOL
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Where did you get that? If only that were the case. Alas, that is not so.
That will depend on the level of activation required with the flux, based on the surface metals that you wish to solder to. Anything with halides will leave a residue which is not nice, especially with high strandcount wires.
And it can be an extreme concern depending on the level of reliability you require....to wit, the cost of repairing a failure. Some projects, the cost of repair is roughly 10e6 dollars per day, with the minimum downtime of 7 days. Some projects, a simple solder joint failure can cost (and actually did) in excess of 150 million dollars.
If that's your idea of a meet and greet, then you have some interpersonal skills that need development.
For a labor intensive production line, that's actually not a bad ratio. My experience with military component production was typically at the level of 20X. Try working an environment where that ratio is a thousand.
I believe you will find a lot of very high falutin soldering experience here, perhaps you should ask pertinent questions instead of your current tact.
jn
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You make a key emphasis point about temperature here...
How does this play a role and why would you want to induce a triboelectric affect into an insulator like PTFE IF it's at high temp...
hmm...
Where is PTFE on the chart?
You guys are sneaky and his sneak point here is TEMP
Please explain to a dumbass like me!
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