I see, Cambridge Dictionary Online is not good enough - let's try Oxford instead: measure: definition of measure in Oxford dictionary (British & World English)
Yet ENIG is one of if not the most common surface finish for both RoHS and lead based processes, and long as your processes are controlled you can get reliability, though for long term 7+ years you have to use tin/lead eutectic solders. Also you have to have the solder in your wave soldering system checked every few months to check for contamination, but as traditional wave solder machines are less common these days, being replaced by selective soldering, this is not such a hardships as these tend to have smaller reservoirs of solder.
The IPC has a wealth of info on soldering, solderbility etc (as well as NASA and the National physics lab), as 6 billion small surface mount components are placed a day it is and has been well studied over the years, so there is a shed load of info out there...
The IPC has a wealth of info on soldering, solderbility etc (as well as NASA and the National physics lab), as 6 billion small surface mount components are placed a day it is and has been well studied over the years, so there is a shed load of info out there...
I note you give definition 2. What was definition 1?fas42 said:
To a scientist/engineer 'measure' involves numbers. Arty people may use it in a weaker sense, derived from the full sense, but we should not copy them when talking about audio engineering. Should we copy their misuse of 'quantum leap' (a big leap) when quantum transitions are actually incredibly small? Should we copy them in using 'literally' to mean exactly the opposite of literally? Sadly, dictionaries seem to have given up the task of encouraging correct usage; now they merely record incorrect usage and so perpetuate what they should deprecate. If you want to hear something really silly said about English, just listen to almost any professor of English.
I refer to the main definition of measure...which comes from:
Online Etymology Dictionary
If you wanna get all etymological with me Frank bring it on
Online Etymology Dictionary
If you wanna get all etymological with me Frank bring it on
I have an old copy of the Cambridge English Dictionary. In the front it has a nice chart showing how all languages derived from the original Aryan! I am pretty sure they don't support that theory any more.
For the Peanut Gallery here as some PSSR curves for simple IC regulators. Input is DC with a sine wave added.
For the Peanut Gallery here as some PSSR curves for simple IC regulators. Input is DC with a sine wave added.
Attachments
Not at all, illuminating and fascinating
Sounds like we should have a soldering thread.Well the good professor has to write something and publish, or she or he doesn't keep the job.
Yes, the situation with the "living language" is disgraceful. A friend says I shouldn't be a grammar nazi if I can still understand what people are trying to express. I agreed with her that I could bear up under the onslaught of there their they're and it's its, but have a more difficult time with "linear" versus "constant", "nonlinear" versus "variable", and the wholesale application of "digital" wherever something is switching between roughly two discrete levels. And things get even worse when wholly non-technical writers think they understand linear and nonlinear, let alone quantum. Occasionally I will read book reviews where the critic will take these misuses on, but he or she is clearly viewed by most as churlish and just not possessed of the proper spirit.
What
Maybe they are youngsters without practice (reading theory mostly)..
It is soon 40 years since I got my military soldering certificate and I have practiced since (and some 10 years previous)..
The soldering expertise are really needed when soldering pure gold conductors..
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No, I'm afraid your wrong the top of that language tree was simply renamed proto-indo-european for mostly political reasons.
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Where do you solder pure gold conductors?What
Maybe they are youngsters without practice (reading theory mostly)..
It is soon 40 years since I got my military soldering certificate and I have practiced since (and some 10 years previous)..
The soldering expertise are really needed when soldering pure gold conductors..
My only experience with pure gold conductors was with military hybrids, where the wires were .0007 inch, .001 inch, and .002 inch. All we could do is T/C and U/S welding. Any solder whatsoever would just consume those in the melt.
Gold plated, different story. For the mil rated surface mount parts I made in a production line, we had to specify 50 microinches of matte gold finish over a nickel flash of 10 microinches over a molybdenum surface. The nickel prevented diffusion of the gold, and provided a surface that could be soldered to, as moly was not solderable. Same with alumina, it had a sintered moly/mag top layer with nickel flash and 50 micro gold.
After the hermetic surface mount part was finished through production, I had to dip in eutectic tin/lead to remove the gold and make the surfaces amenable to a 6 month shelf. They had to survive a bake and salt spray mil spec.
Now, as marce points out, there are better specs on finish for pcb's. Over the years, they learned what thickness of gold they had to stay below in order to prevent embrittlement, it just limits shelf life.
40 years...so, just lead/tin eutectic? Mil is exempt from lead free.
Takes getting used to frosty joints, no? I had to learn 50/50 lead/indium, 95/5 tin/lead, 95/5 lead/tin, 96/4 tin/silver, gold/germanium and gold/tin. None were covered by mil spec visual criteria, so we had to make it up as we went along..
jn
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I use only pure gold conductors -> inside amplifiers, DACs and cables (digital and analog).. Loudspeaker cables and mains cables are silver and gold due to cost.. PCBs are gold plated..
What you have experienced -> soldering pure gold results normally in the gold transforming to a gray substance and some millimeter of the gold have gone forever.. Thick gold conductors are the most easy, but 0.2 millimeter diameter witch I use for wire in turntable arms are quite tricky.
However it took only a day and 10 millimeter lost gold to find a working solution with the solder stations and solder tin of newer date. In the military we had PCBs where the traces was pure gold and components had a minimum of gold plating of the legs..
With gold plated items like my PCBs the gold are directly put on the copper with no other metals involved.
With this method there are no silk screen or solder stop on the PCBs.
Even PCBs that have been exposed to air for more than 10 years only need a cleaning before soldering.
Embrittlement have not been discovered or regarded as a issue
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No, the proto-indo-european tree is quite different than what is in my Cambridge dictionary. It is an attempt to trace language development. It does not claim to show all languages. There is a long scholarly history to it.
The one I mentioned claims all languages came from one source in a hierarchical structure. It has been widely discredited. The only exception of course seems to be from you!
The wires I worked with were 25 to 50 microns diameter. They were consumed pretty much instantly. It's like trying to dip a 1 inch by half inch copper braid made with .001 inch wires into a solder pot. After 4 or 5 seconds, half the braid is gone..
Your material design choices would never be useable for hi rel or mil parts. But if you're happy, good for you. In the end, that's all that counts.
jn
I know, but it is still doable without the gold get consumed.
I took the best from the military specced PCBs and parts and avoided the safety issues that would compromise... Inside equipment I use air as dielectricum as as I use gold conductors.
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