Replace the cord on all radios, tvs and other electronics every five years.

Nov 27, 2017 44 Replies

That is obsolete, use CAT6A these days

The problem with CAT5/6 cables is that each pair has a different pitch (turns per meter) originally to reduce crosstalk. What happens if you connect such pairs in parallel, that must have some severe sonic effects.

UTP vs. FTP vs. STP ?

Some of the pair-shielded types (FFTP, SFTP, like that) don't have different twists; some do.

John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com

CAT3 has all pairs with the same twist.

CAT5 has different twists for each pair: I couldn't find any info for CAT6 and I don't have any CAT6 cable ends handy to check. My guess(tm) it's the same as CAT5.

Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

I've tested a lot (too many) of shielded-pair CAT6, for use in an application where pair skew matters, not Ethernet. Some had uniform twists, some didn't. The cable skew specs suggest which is which.

Cables without individual pair shields seem to always have different twists.

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John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com

Gordian knot[1].

My guess(tm) is that some enterprising researcher had already written a report on the inductance of various knots for an Ig Nobel Prize entry. I couldn't find anything, so that area of research is available for those with too much time on their hands. However, I did find some comments on tying knots in power cords allegedly preventing power surges caused by lightning strikes. Sorry, but no comparisons of the effectiveness of different types of knots. My guess(tm) is that something that resembles a coil will be the least disgusting. If one wants something that actually works, adding some ferrite cores like this would be better:

[1] Way back in college, I instigated the short lived fad of sending very difficult to open Christmas packages. Besides the Matryoshka doll style boxes and packing, the package was tied with a fair approximation of a Gordian knot. If we had Tyvex and Kevlar at the time, I would have used them.

We return now to what I should be doing.

Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

We should return to what you are doing???????????? No way brother. Go soak your head.

Make sure you get the twists the right direction or you'll cancel all the acoustic detail.

When color TV came out a guy in some local TV shop told customers they will have to re-fill the color after a year.

Reinhardt

Yes that's correct terminology.

I have some rubber cables here, 40+ years old and they seem as good as new. and some 10 year old PVC cables with cracked insulation.

This email has not been checked by half-arsed antivirus software

Reminds me of one of the cruder colour tv schemes. One placed a plastic film over the screen that was slightly tinted blue across the top, pink across the middle, green across the bottom.

NT

Yes, the PAT (portable appliance testing) sticky tags (that are requred now for health and safety) seem to leach a lot of placticizers out of the cable, turning the sticker into a very sticky mess each year, and presumably depriving the cable of whatever benefit (flexibility?) was due to the plasticizer in the first place. If it gets to the point where the insulation cracks and the wiring shorts out, there is usually a lot of kindling (PAT labels of all the other cords) nearby, which would presumably help to sustain the fire. I wonder whether they have done a risk assessment. Maybe if the labels were printed on asbestos paper...

In some places they were allowed to pass on the cost of such maintenence / upgrades to customers, plus a fixed percentage markup as profit. How do you maximise profit, when it is a fixed percentage of the repair/upgrade cost? Make sure the repairs/upgrades are as expensive and often as possible. If anyone complains about prices, blame renewable energy.

This would be a good choke.

Mikek

Not exactly what you are talking about, but Edward Witten is a particularly enterprising researcher in string theory, and I do like the idea of matter merely being knots in space-time - regular four-dimensional space-time app arently won't do, as you seem to need an odd number of dimensions to get kn ots (or knot-like structures) but since string theory seems to like 11-dime nsional space, it may eventually work out.

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With 10^500 possible universes for it work out in, this isn't a particularl y bold claim.

Bill Sloman, Sydney

hissss.

John Larkin Highland Technology, Inc picosecond timing precision measurement jlarkin att highlandtechnology dott com http://www.highlandtechnology.com

Ah, yes, see what happens when pot is legal and s*it-for-brains is president.

Cats, coffee, chocolate...vices to live by Please don't feed the trolls. Killfile and ignore them so they will go away.

Had you never found out that you have to replace the wings on a pig about every 5 years, else they cant fly either ?

Regards, Adrian Jansen

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