Do you by chance refer to "The Man From U.N.C.L.E." and Ducky as Iliya Kuryakin?
I find the Captain Gallant with Buster Crabbe to be one of the most interesting shows. Filmed on location in Foreign Legion outposts in Morocco with real FFL members as extras.
BTY since JN has not posted, it was interesting a local youth helped on the project, very young Matty Matic. I think he has a real future in engineering.
BTY since JN has not posted, it was interesting a local youth helped on the project, very young Matty Matic. I think he has a real future in engineering.
Very un PC. When in doubt kill somebody! But a real period piece.
Did you pick up on the Matty Matic reference?
Measuring that level of inductance to any accuracy does require both care and the correct equipment. I'd be happy to do so if you ever wish.
1 milliohm per leg. Typical contact resistance errors can easily swamp that. Did you use a 4 wire dvm, or did you set up a constant current source and use a good dvm in millivolt range?
Contact resistance can easily compromise that level of measurements. Single wire, was it the heavily deformed one or one off the spool. Have you been able to repeatedly demonstrate that heavily work hardening the copper wire makes any significant difference?
jn
I suspect you can come up with your own twisted pair.
I did buy a "Surprise Package" from Electronic Goldmine, as every so often I get curious. Lately they all have been real junk, until this one. A few interesting semiconductors, many useful, bunches of thick film resistor networks, a decent assortment of Japanese electrolytic's, a real pile of 1 nF ceramics, a few hundred assorted Dale, IRC and Corning precision resistors and finally a bunch of molded inductors.Using my GR Digibridge I sorted the parts. The 22 uH labeled inductors measured 23.1. The 39 uH came in at 39.4. All the resistors came in within 1% of their marked values. So The parts all seemed to be good surplus and the bridge working as I expect.
The bridge is a 4 wire gizmo with a clever holder the grabs both sides of a part lead so it is invisible to the casual user. So yes all my measurements are Kelvin connections.
As to distortion measurements on wires. It seems when you have a contact problem it is around -145 or higher! It also changes when you swap directions. These days I am getting decent clean readings down to -160 for special test jigs.
Yes measuring the wire before and after abuse shows changes of 3-5 dB on half a dozen samples. But let's wait and see if anyone else can get similar results.
I do remember someone commenting they didn't see these problems in RF stuff, so I guess they didn't read Demian's cite. P.I.M. is a big issue in cell phone towers. So I don't think the issue is if there is an increase in distortion, just how much. Also the issues I think are diffusion (meaning that HF and LF propagate at different velocities) and distortion work differently in conductors. Small wires are more affected by defects and large cables may have more diffusion. So that leads me to the proposal that there is an optimum wire diameter for a given signal (Current and frequency issues.)
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I suspect you can come up with your own twisted pair.
Shouldn't need it, as I said simple rearrangement of what is a single loop of current in two wires and four terminating resistors will yield a measurement of voltage error across the wires alone. With identical currents the order of the conductors can't matter, or we are again talking about violation of first principles. They only need to be two workhardened wires, they could be twisted together but should not need to be. The voltage across the wires is so small that resolving the 2nd harmonic due to the wire ALONE should be easy the source residual now suppressed by 60 or more dB. A simple divider of the total source resistances and the wire at the same currents HAS to show the same answer.
BTW the original number of 100mV rms (assuming the AP is 600 Ohms) is not really a small current where this so called effect would not have shown up anywhere.
EDIT - Still have not seen presented any physical model of a process that could have these properties, at a quick glance only an abrupt discontinuity could have constantly increasing distortion, also f1-f2 is an even order product what are those implications?
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I'll remind you ADSL works over miles of the most convoluted and ancient infrastructure of twisted pairs you can imagine (sometimes literally 1000's of feet of 100yr. old wire). The signals at the end points often have huge attenuation and bitrate is directly effected by distortion.
Diffusion, a new process enters the fray, references?
The descriptions of R, L, G, and C are amusing.
Nothing here about distortion or variance with scale.
EDIT - Before you say "misunderstand" again, if that is what you want to call diffusion fine we have discussed transmission on lossy lines before no harmonic distortion there. I usually call it dispersion since a diffusion process is a limiting case, but in any case I find larger cables better, i.e. RG174 is pretty bad compared to RG58.
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My bad I meant dispersion and either I or auto correct got it to diffusion.
The distortion is one effect the dispersion is the other, both change the signal. So if you aim to minimize one effect the other pops up. Dispersion does not cause harmonic distortion. SY does.
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