Some people like copper clad steel wire for its pull strength. For HF coax where the steel core won't harm much, the extra pull strength and cost savings would be popular.
Now I wonder but apparently some like to pull their audio wires?! 🙂
Seriously, till now the experiences with iron in parts has only been so so. It does not seem a material chosen because of optimal performance to say the least. That many if not almost all manufacturers use it does not make it best choice. Probably best profit.
Seriously, till now the experiences with iron in parts has only been so so. It does not seem a material chosen because of optimal performance to say the least. That many if not almost all manufacturers use it does not make it best choice. Probably best profit.
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If you run cables inside of existing walls and building structures, they don't crawl to the destination on their own power. You have to feed in a spring steel fish tape to the remote end, attach the cable to the fish tape, and then pull the cable through the wall. If the cable can't handle it, then you get a break somewhere inside of the wall - no fun at all.
Therefor we use cheap piping to pull cables through as an adequate solution for decades now. Makes the job and renovations/pulling extra cables in the future easier.
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Digressing a little, and please correct me if I’m wrong.
I’m wondering how many tin plated steel lead components end up in the signal path of audio gear? I am guessing that manufacturers of high end equipment are a little more pedantic about quality components and solder used as well, but I doubt that the ‘High Street’ HiFi store gear does?
It appears that steel and the tin plating only having about a fifteenth conductivity that of copper, probably the solder isn’t much better either…
I’m wondering how many tin plated steel lead components end up in the signal path of audio gear? I am guessing that manufacturers of high end equipment are a little more pedantic about quality components and solder used as well, but I doubt that the ‘High Street’ HiFi store gear does?
It appears that steel and the tin plating only having about a fifteenth conductivity that of copper, probably the solder isn’t much better either…
You realize for most signal level audio circuits steel leads are a non-issue - the currents, fields and inductive impedances are too tiny to matter.
A steel speaker terminal post on the other hand, with amps of signal current and forming a divider with a few ohms of the speaker is a different story.
BTW how much conductivity do you need in the lead of a 1k resistor? 3cm of 0.6mm copper wire is 1.8 milliohms, so a steel wire of same dimensions is about 27 milliohms, compared to 1000000 milliohms of the resistor itself - supremely irrelevant!! Also the much larger cross-sectional area of a component lead compared to standard PCB traces is being ignored - 2mm wide trace in 1oz pcb has cross-section of 0.07mm^2, whereas a 0.6mm diameter wire has 0.28 mm^2 - PCB trace resistance is likely to be dominant in most circuit even if all the leads are steel. You really need to do that back-of-the-envelope calculation before leaping to conclusions.
Typical signal current of a few mA can only generate a few milliteslas of field in/around the component wires, way below the start of ferromagnetic non-linearity, and the inductive reactance itself is typically orders of magnitude below the component impedance anyway, so any residual non-linearity is diluted hugely. So does anyone have any measurements of linearity differences between a copper and steel leaded 1k resistor at say 10Vrms? This isn't a hard test to perform for those with good audio analyzers - it would be illuminating to repeat for lower resistor values until the currents involved are large enough for an effect to become measureable - that's a datapoint I think we need.
Given that steel (unless annealed) isn't magnetically super-soft, it may not actually be activated at all at these low MMFs. Rolled steel needs about 100A/m current density to start responding from what I can see, and many annealed irons and steels seem to only start at 10A/m - permalloy being a notable exception: https://www.femm.info/wiki/SoftMagneticMaterials
So go calculate the current needed in a 0.6mm wire before H becomes 100A/m....
What you might have to worry about is power dissipation - similar sized resistors with steel leads cannot conduct as much heat down the leads as copper leaded versions. But again - at solid-state signal levels, high power dissipation is rare for signal stuff.
So basically this is an issue for high power circuitry only, perhaps especially the feedback resistors in a power amp and the wiring from output transistors to the terminal.
A steel speaker terminal post on the other hand, with amps of signal current and forming a divider with a few ohms of the speaker is a different story.
BTW how much conductivity do you need in the lead of a 1k resistor? 3cm of 0.6mm copper wire is 1.8 milliohms, so a steel wire of same dimensions is about 27 milliohms, compared to 1000000 milliohms of the resistor itself - supremely irrelevant!! Also the much larger cross-sectional area of a component lead compared to standard PCB traces is being ignored - 2mm wide trace in 1oz pcb has cross-section of 0.07mm^2, whereas a 0.6mm diameter wire has 0.28 mm^2 - PCB trace resistance is likely to be dominant in most circuit even if all the leads are steel. You really need to do that back-of-the-envelope calculation before leaping to conclusions.
Typical signal current of a few mA can only generate a few milliteslas of field in/around the component wires, way below the start of ferromagnetic non-linearity, and the inductive reactance itself is typically orders of magnitude below the component impedance anyway, so any residual non-linearity is diluted hugely. So does anyone have any measurements of linearity differences between a copper and steel leaded 1k resistor at say 10Vrms? This isn't a hard test to perform for those with good audio analyzers - it would be illuminating to repeat for lower resistor values until the currents involved are large enough for an effect to become measureable - that's a datapoint I think we need.
Given that steel (unless annealed) isn't magnetically super-soft, it may not actually be activated at all at these low MMFs. Rolled steel needs about 100A/m current density to start responding from what I can see, and many annealed irons and steels seem to only start at 10A/m - permalloy being a notable exception: https://www.femm.info/wiki/SoftMagneticMaterials
So go calculate the current needed in a 0.6mm wire before H becomes 100A/m....
What you might have to worry about is power dissipation - similar sized resistors with steel leads cannot conduct as much heat down the leads as copper leaded versions. But again - at solid-state signal levels, high power dissipation is rare for signal stuff.
So basically this is an issue for high power circuitry only, perhaps especially the feedback resistors in a power amp and the wiring from output transistors to the terminal.
What I see as a challenge is the "solderability" of those plated iron/steel/"anymetal" lead wired components and certainly when lead free solder is used. What will happen with the connections over time? Secondly the corrosion in moist environments is an issue.
Be it manufacturers of high end equipment or producers ‘High Street’ HiFi store gear, neither need to care about longevity as the EU thinks 2 years is a long time for warranty. In other words: one needs to replace consumer graded stuff every 2 years. This is the harsh reality, sorry.
Be it manufacturers of high end equipment or producers ‘High Street’ HiFi store gear, neither need to care about longevity as the EU thinks 2 years is a long time for warranty. In other words: one needs to replace consumer graded stuff every 2 years. This is the harsh reality, sorry.
Only a tiny fraction of the high end manufacturers pay any attention. Normally it is the usual scam operation run by marketeers and meter heads, masquerading as high end and centered around a very expensive case.
One does need to be careful about ferrous metals if it's used near something sensitive to magnetic fields.
I made that mistake while building a reasonably sensitive hall probe for a project. I wasted something like four hours trying to figure out why my measurements looked so screwy. The problem turned out to be an indicator LED on my test jig with ferrous leads. Ridiculous waste of time.
I made that mistake while building a reasonably sensitive hall probe for a project. I wasted something like four hours trying to figure out why my measurements looked so screwy. The problem turned out to be an indicator LED on my test jig with ferrous leads. Ridiculous waste of time.
Most factories are in China, and price gouging from purchasers side to suppliers is common.
And the Chinese have taken over many European brands, they can sell a device which ordinarily sells for $20 for $150, just because of the brand and perceived quality.
In either case, the sellers down the chain will try for maximum profit.
Never mind quality, they do not give life long warranty.
You want quality?
Buy Japanese and European sets made no later than 1995.
Rugged, and trouble free for the most part.
New stuff is mostly made in China, and if it sells in low volumes, or at cut price, it is bad stuff inside, only the big makers like Apple can insist on a particular quality level.
And you will not break the seals during warranty, and come to know what it was only after expiry.
Then you have no recourse.
And the Chinese have taken over many European brands, they can sell a device which ordinarily sells for $20 for $150, just because of the brand and perceived quality.
In either case, the sellers down the chain will try for maximum profit.
Never mind quality, they do not give life long warranty.
You want quality?
Buy Japanese and European sets made no later than 1995.
Rugged, and trouble free for the most part.
New stuff is mostly made in China, and if it sells in low volumes, or at cut price, it is bad stuff inside, only the big makers like Apple can insist on a particular quality level.
And you will not break the seals during warranty, and come to know what it was only after expiry.
Then you have no recourse.
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Ferrous leads are common in LEDs, unless they are top brand like HP.
Try and find those if you need such quality.
Easier, put a car bulb.
The leads are normally tin plated iron, and if used within 6 months or so, the corrosion does not have much issue.
After that, handle as if iron, use abrasion and strong flux to get a good joint.
Try and find those if you need such quality.
Easier, put a car bulb.
The leads are normally tin plated iron, and if used within 6 months or so, the corrosion does not have much issue.
After that, handle as if iron, use abrasion and strong flux to get a good joint.
One must break the seals to know how crappy stuff is made and take measures against short longevity straight away 🙂 It comes with buying low cost stuff.
Recently I noticed that even a 25 Euro MA12070 based amplifier had various seals warning not to open the device because of warranty reasons. Do they really expect that one sends the device back when it malfunctions?
Recently I noticed that even a 25 Euro MA12070 based amplifier had various seals warning not to open the device because of warranty reasons. Do they really expect that one sends the device back when it malfunctions?
Well, plated iron leads are cheaper, so manufacturers will use those.
As devices move to surface mount (at greater inconvenience to the home constructor in the main) you may find that SMD suits your requirement, even if you have to build a small carrier board for it?