I needed to replace a 1/8" stereo plug on a cord. I found on ebay a pack
of three 1/8" stereo plugs from China, for about $2. I dont normally
order from China, but for the price and since I was in no hurry for
them, I bought them.

That was a mistake. They are NOT stereo, they are THREE CHANNEL. The tip
of the plug has THREE contacts, (plus the grounded base). What the heck
are they for? I have never seen any 3 prong 1/8" jacks on anything.

Yea, I could just ground the uppermost terminal so it acts as a stereo
plug, but it gets worse. Under the shell, I found a solder on ground
contact. But none of the three conductors have any contacts attached to
them. There are just three pieces of "rod" sticking out the back, with
the insulation in between. I would have to wrap the wires around them,
and solder them and by the time I manage to do all that in that tiny
space, I'd probably melt the insulation between the sections and unless
they wires were hair thin, they would short against the ground terminal.

For the small price, I am not gonna make a big deal out of it. I'll just
have to order some properly made plugs from an American manufacturer,
and use these worthless plugs for a conversation piece.

On Saturday, July 1, 2017 at 5:08:38 AM UTC-4, wrote:
I needed to replace a 1/8" stereo plug on a cord. I found on ebay a pack
of three 1/8" stereo plugs from China, for about $2. I dont normally
order from China, but for the price and since I was in no hurry for
them, I bought them.

That was a mistake. They are NOT stereo, they are THREE CHANNEL. The tip
of the plug has THREE contacts, (plus the grounded base). What the heck
are they for? I have never seen any 3 prong 1/8" jacks on anything.

Yea, I could just ground the uppermost terminal so it acts as a stereo
plug, but it gets worse. Under the shell, I found a solder on ground
contact. But none of the three conductors have any contacts attached to
them. There are just three pieces of "rod" sticking out the back, with
the insulation in between. I would have to wrap the wires around them,
and solder them and by the time I manage to do all that in that tiny
space, I'd probably melt the insulation between the sections and unless
they wires were hair thin, they would short against the ground terminal.

For the small price, I am not gonna make a big deal out of it. I'll just
have to order some properly made plugs from an American manufacturer,
and use these worthless plugs for a conversation piece.



A link would be nice, but I've seen plugs like what you're describing used for plug in keyboards, controllers, and even small power supplies - anything that needs a quick disconnect.

On Sat, 01 Jul 2017 04:04:35 -0400, wrote:

I needed to replace a 1/8" stereo plug on a cord. I found on ebay a pack
of three 1/8" stereo plugs from China, for about $2. I dont normally
order from China, but for the price and since I was in no hurry for
them, I bought them.

That was a mistake. They are NOT stereo, they are THREE CHANNEL. The tip
of the plug has THREE contacts, (plus the grounded base). What the heck
are they for? I have never seen any 3 prong 1/8" jacks on anything.

Yea, I could just ground the uppermost terminal so it acts as a stereo
plug, but it gets worse. Under the shell, I found a solder on ground
contact. But none of the three conductors have any contacts attached to
them. There are just three pieces of "rod" sticking out the back, with
the insulation in between. I would have to wrap the wires around them,
and solder them and by the time I manage to do all that in that tiny
space, I'd probably melt the insulation between the sections and unless
they wires were hair thin, they would short against the ground terminal.

For the small price, I am not gonna make a big deal out of it. I'll just
have to order some properly made plugs from an American manufacturer,
and use these worthless plugs for a conversation piece.

My Samsung photo mobile has a plug like that for earphone and
microphone made before USB became standard.

Steve

--
Neural Network Software for Windows http://www.npsnn.com

On 1/07/2017 6:04 PM, wrote:
I needed to replace a 1/8" stereo plug on a cord. I found on ebay a pack
of three 1/8" stereo plugs from China, for about $2. I dont normally
order from China, but for the price and since I was in no hurry for
them, I bought them.

That was a mistake. They are NOT stereo, they are THREE CHANNEL. The tip
of the plug has THREE contacts, (plus the grounded base). What the heck
are they for? I have never seen any 3 prong 1/8" jacks on anything.

**They are used for a wide variety of things. One is for two stereo
channels and one video.


Yea, I could just ground the uppermost terminal so it acts as a stereo
plug, but it gets worse. Under the shell, I found a solder on ground
contact. But none of the three conductors have any contacts attached to
them. There are just three pieces of "rod" sticking out the back, with
the insulation in between. I would have to wrap the wires around them,
and solder them and by the time I manage to do all that in that tiny
space, I'd probably melt the insulation between the sections and unless
they wires were hair thin, they would short against the ground terminal.

For the small price, I am not gonna make a big deal out of it. I'll just
have to order some properly made plugs from an American manufacturer,
and use these worthless plugs for a conversation piece.

**"American manufacturer"? Don't tell me you've swallowed the Trump
Kool-Aide? I doubt that 3.5mm jack plugs were ever manufactured in the
US. If they were, it was likely before the early 1960s. If want REAL
quality, then look at Neutrik. Best 3.5mm jack plugs in the business.
You guys really have to get over this 'inch' bull****. Everyone on the
planet, save a tiny 5% of the planetary population has embraced the
Metric system. Hell, engineers and scientists in the US use it.



--
Trevor Wilson
www.rageaudio.com.au

wrote:

I needed to replace a 1/8" stereo plug on a cord. I found on ebay a pack
of three 1/8" stereo plugs from China, for about $2. I dont normally
order from China, but for the price and since I was in no hurry for
them, I bought them.

That was a mistake. They are NOT stereo, they are THREE CHANNEL. The tip
of the plug has THREE contacts, (plus the grounded base). What the heck
are they for? I have never seen any 3 prong 1/8" jacks on anything.

You seem to have bought TRRS rather than TRS plugs, mobile phones often
use them for stereo headsets with mic (and sometimes answer/end call
buttons, or FF/REW buttons)

On Saturday, July 1, 2017 at 5:08:38 AM UTC-4, wrote:
I needed to replace a 1/8" stereo plug on a cord. I found on ebay a pack
of three 1/8" stereo plugs from China, for about $2. I dont normally
order from China, but for the price and since I was in no hurry for
them, I bought them.

That was a mistake. They are NOT stereo, they are THREE CHANNEL. The tip
of the plug has THREE contacts, (plus the grounded base). What the heck
are they for? I have never seen any 3 prong 1/8" jacks on anything.

Yea, I could just ground the uppermost terminal so it acts as a stereo
plug, but it gets worse. Under the shell, I found a solder on ground
contact. But none of the three conductors have any contacts attached to
them. There are just three pieces of "rod" sticking out the back, with
the insulation in between. I would have to wrap the wires around them,
and solder them and by the time I manage to do all that in that tiny
space, I'd probably melt the insulation between the sections and unless
they wires were hair thin, they would short against the ground terminal.

For the small price, I am not gonna make a big deal out of it. I'll just
have to order some properly made plugs from an American manufacturer,
and use these worthless plugs for a conversation piece.



I've also seen them on X-Box headsets now that I think about it.

On Saturday, July 1, 2017 at 6:31:22 AM UTC-4, Trevor Wilson wrote:


**"American manufacturer"? Don't tell me you've swallowed the Trump
Kool-Aide?

Trump is NOT talking about replacing every imported item with a domestic one. That's the leftist media's binary spin on this: If Trump talks about reducing the trade deficit, then it means he wants to stop *all* imports and make everything domestically. Not happening - not his plan.

Americans don't have any problem buying German, British, Canadian, Swiss etc. imports as we know they aren't built strictly for price. While the Chinese are not genetically predisposed to making junk, a very large portion of Chinese sourced pieces/parts are indeed crap. There are however many good parts sourced from China, it's just not the norm from what I've seen. Japan had the same (deserved) reputation until they started making better quality stuff. Americans no longer have any problem buying a Japanese sourced component as we perceive them to be of higher quality that Chinese stuff.


You guys really have to get over this 'inch' bull****. Everyone on the
planet, save a tiny 5% of the planetary population has embraced the
Metric system. Hell, engineers and scientists in the US use it.

Americans (and I'm guessing the Brits) are "bilingual" when it comes to measurements (except the old guys like !). We use both interchangeably and seamlessly. It's not an issue here.

OTOH, we call the plug in question 3.5mm as well. I didn't realize they're also referred to as 1/8 inch.

John-Del wrote on 7/1/2017 1:51 PM:
On Saturday, July 1, 2017 at 6:31:22 AM UTC-4, Trevor Wilson wrote:


**"American manufacturer"? Don't tell me you've swallowed the Trump
Kool-Aide?

Trump is NOT talking about replacing every imported item with a domestic one. That's the leftist media's binary spin on this: If Trump talks about reducing the trade deficit, then it means he wants to stop *all* imports and make everything domestically. Not happening - not his plan.

Americans don't have any problem buying German, British, Canadian, Swiss etc. imports as we know they aren't built strictly for price. While the Chinese are not genetically predisposed to making junk, a very large portion of Chinese sourced pieces/parts are indeed crap. There are however many good parts sourced from China, it's just not the norm from what I've seen.

I'll share with you a secret. If we didn't buy "crap" from China, they
wouldn't keep sending it!!! They only make what people buy, nothing more,
nothing less.


Japan had the same (deserved) reputation until they started making better quality stuff. Americans no longer have any problem buying a Japanese sourced component as we perceive them to be of higher quality that Chinese stuff.

Many times we perceive Japanese goods to be superior to US made goods. I
seem to recall they nearly (or maybe did) bankrupt the US automakers at one
point, not to mention many other goods they seem to excel at making.


You guys really have to get over this 'inch' bull****. Everyone on the
planet, save a tiny 5% of the planetary population has embraced the
Metric system. Hell, engineers and scientists in the US use it.

Americans (and I'm guessing the Brits) are "bilingual" when it comes to measurements (except the old guys like !). We use both interchangeably and seamlessly. It's not an issue here.

Hardly. *Some* engineers use both systems. I recall all of the mechanical
designs at a company I worked for were in inches. I asked about that one
time and they made is clear they had no reason to change.

The average guy on the street has no idea how large a gram is or a ml or a
mm or a hectare, even though they are printed on the sides of the things we
buy (well, maybe not the hectare).


OTOH, we call the plug in question 3.5mm as well. I didn't realize they're also referred to as 1/8 inch.

They've been 1/8 inch since they appeared on the sides of Japanese
transistor radios in the 60's.

I'm actually surprised oldschool didn't spot the three way plug. They have
come in mono and stereo for a long time. I expect he can still use the
plugs he got as stereo plugs. He just needs to short together two sections.
I guess he'd have to figure out which two sections though.

--

Rick C

In article ,
says...

On Saturday, July 1, 2017 at 6:31:22 AM UTC-4, Trevor Wilson wrote:

Trump is NOT talking about replacing every imported item with a domestic
one. That's the leftist media's binary spin on this: If Trump talks
about reducing the trade deficit, then it means he wants to stop *all*
imports and make everything domestically. Not happening - not his plan.

Americans don't have any problem buying German, British, Canadian, Swiss etc. imports as we know they aren't built strictly for price. While the Chinese are not genetically predisposed to making junk, a very large portion of Chinese sourced pieces/parts are indeed crap. There are however many good parts sourced from China, it's just not the norm from what I've seen. Japan had the same (deserved) reputation
until they started making better quality stuff. Americans no longer have any problem buying a Japanese sourced component as we perceive them to be of higher quality that Chinese stuff.


I don't care where an item is made. I buy for quality, or at least what
I think is quality in my price range. Never could get an American car
to last. Started buying the Japan cars around 1980. Did buy a Ford in
1995 and it turned out that model was a piece of junk. Went back to the
Japan ones.

Around 1972 I took a tour of the local TV station. They had just gotten
in a few Japan Cameras about 6 months before and were bragging on them
and how they were going to get more as the money allowed for it.

China puts out lots of junk at junk prices. However I have found some
of their electronics to be every bit as good as the Japan ones that have
been highly rated for many years. Isn't China where many of the Apple
item are made ?

If the American companies would quit paying the higher ups in a company
large ammouts of money and put it into better quality I am sure lots of
jobs would come back to America. Really looks bad to go to a large
company and see a row of almost new high dollar cars for the wheels, and
the others old used cars for the workers.

On Saturday, July 1, 2017 at 3:31:22 AM UTC-7, Trevor Wilson wrote:
On 1/07/2017 6:04 PM, wrote:
For the small price, I am not gonna make a big deal out of it. I'll just
have to order some properly made plugs from an American manufacturer,
and use these worthless plugs for a conversation piece.

**"American manufacturer"? Don't tell me you've swallowed the Trump
Kool-Aide?
By their actions, Donald and Ivanka clearly believe in the superiority of things made in China, since that is where their ties, shoes, and other things are manufactured. The Donald may promote American manufacturing, but that is as credible as anything else that comes out of his mouth.

He has all the honor of someone who stole the family crest of someone else (only modified by removing the Latin word "Integritas" and replacing it with "Trump"), and who tried to convince people that his self-created Time magazine cover was genuine. It is reasonable to assert that all the Trumpettes are just as truthful, honorable and honest.

On Saturday, July 1, 2017 at 10:51:53 AM UTC-7, John-Del wrote:
Americans don't have any problem buying German, British, Canadian, Swiss etc.
imports as we know they aren't built strictly for price.
Despite NAFTA, Americans cannot easily purchase cheaper drugs from Canada because it would make it harder for the drug companies to raise their prices..

Americans (and I'm guessing the Brits) are "bilingual" when it comes to
measurements (except the old guys like !). We use both
interchangeably and seamlessly. It's not an issue here.
There are lots of stories about problems caused by confusion between metric and Imperial measures. Two that come to mind are the spy satellite that pointed up to the sky, and the Mars probe that crashed.

I think the UK is metricated. The older Imperial units appear when they are being deliberately nostalgic, like in historical dramas. The last I heard, Ireland (not a part of a UK) had an amusing mixture where speed limits were in mph and road distances were in km.

In article , says...

Americans (and I'm guessing the Brits) are "bilingual" when it comes
to measurements (except the old guys like !). We use
both interchangeably and seamlessly. It's not an issue here.

Hardly. *Some* engineers use both systems. I recall all of the mechanical
designs at a company I worked for were in inches. I asked about that one
time and they made is clear they had no reason to change.


My son had a Ford that those engineers must have designed. Some bolts
in inches and others were metric.

In article , says...



Japan had the same (deserved) reputation until they started making better quality stuff. Americans no longer have any problem buying a Japanese sourced component as we perceive them to be of higher quality that Chinese stuff.

Many times we perceive Japanese goods to be superior to US made goods. I
seem to recall they nearly (or maybe did) bankrupt the US automakers at one
point, not to mention many other goods they seem to excel at making.



Japan did not almost put the American cars out of business, they did it
to their selves by making high priced junk.

On Sat, 1 Jul 2017 14:37:41 -0400, Ralph Mowery
wrote:

In article ,
says...

On Saturday, July 1, 2017 at 6:31:22 AM UTC-4, Trevor Wilson wrote:

Trump is NOT talking about replacing every imported item with a domestic
one. That's the leftist media's binary spin on this: If Trump talks
about reducing the trade deficit, then it means he wants to stop *all*
imports and make everything domestically. Not happening - not his plan.

Americans don't have any problem buying German, British, Canadian, Swiss etc. imports as we know they aren't built strictly for price. While the Chinese are not genetically predisposed to making junk, a very large portion of Chinese sourced pieces/parts are indeed crap. There are however many good parts sourced from China, it's just not the norm from what I've seen. Japan had the same (deserved) reputation
until they started making better quality stuff. Americans no longer have any problem buying a Japanese sourced component as we perceive them to be of higher quality that Chinese stuff.


I don't care where an item is made. I buy for quality, or at least what
I think is quality in my price range. Never could get an American car
to last. Started buying the Japan cars around 1980. Did buy a Ford in
1995 and it turned out that model was a piece of junk. Went back to the
Japan ones.

Around 1972 I took a tour of the local TV station. They had just gotten
in a few Japan Cameras about 6 months before and were bragging on them
and how they were going to get more as the money allowed for it.

China puts out lots of junk at junk prices. However I have found some
of their electronics to be every bit as good as the Japan ones that have
been highly rated for many years. Isn't China where many of the Apple
item are made ?

If the American companies would quit paying the higher ups in a company
large ammouts of money and put it into better quality I am sure lots of
jobs would come back to America. Really looks bad to go to a large
company and see a row of almost new high dollar cars for the wheels, and
the others old used cars for the workers.
This whole business of imported goods being junk has been going on for
a long time. When the USA was still a British colony all sorts of
goods were made here and exported to Britain. They were considered to
be of lesser quality than British made goods. And they mostly were.
This is because for the most part the goods were made to order. And
the British folks ordering the goods were mostly (I seem to have the
word "most" stuck in my head) interested in low prices. After the USA
was formed the cheap goods were still produced to order and most
(Gawd! there's that word again!) production was still owned by the
British. After the USA started to become industrialized certain
technolgies were prohibited from being exported to the USA from
Britain. Eventually the USA became industrialized, we developed our
own machine tools, the British lost control of our manufacturing, we
marketed our own stuff, and produced goods for internal as well as
external consumption, and quality improved greatly. Fast forward to
the period just after WW2 and the Japanese were in a similar
situation. Their country was devasted and they needed money. Many USA
companies started having cheap goods produced in Japan. These goods
weren't supposed to be of high quality, the USA buyers just wanted
cheap and the quality specs of the goods were lower than domestically
produced goods. But just like people everywhere in the world the
Japanese have the same intrinsic smarts and abilities and when they
could they started to produce their own stuff to their own desired
quality. The same thing happened with Taiwan. And Korea (Korea doing
to Japan what Japan did to us). Now China. India will probably be
next, at least when it comes to heavy industry. Machine tools made in
India are starting to come on the export market. As of now they are
not so good. But they are cheap. Computer controlled machine tools
from India still mostly have Japanese controls. But this will change
soon.
Eric

wrote:

I needed to replace a 1/8" stereo plug on a cord. I found on ebay a pack
of three 1/8" stereo plugs from China, for about $2. I dont normally
order from China, but for the price and since I was in no hurry for
them, I bought them.

That was a mistake. They are NOT stereo, they are THREE CHANNEL. The tip
of the plug has THREE contacts, (plus the grounded base). What the heck
are they for? I have never seen any 3 prong 1/8" jacks on anything.
They are for cell phone headsets and other connections to a phone (like a
car). Left and right audio out, and microphone. Blame Apple.

Jon

On Sat, 1 Jul 2017 12:28:58 -0700 (PDT), "
wrote:

I think the UK is metricated. The older Imperial units appear when they are being deliberately nostalgic, like in historical dramas. The last I heard, Ireland (not a part of a UK) had an amusing mixture where speed limits were in mph and road distances were in km.

The UK started going over to metric measures about 50 years ago but
it's still not complete. Many oldish people, like me, still think in
Imperial units. I think of distances in miles and heights in feet. The
advantage of being an Imperial age is multiple arithmetic bases is not
a problem. Younger metric people are base 10 only!

Steve

--
Neural Network Software for Windows http://www.npsnn.com

On 7/2/2017 3:44 AM, Stephen Wolstenholme wrote:
The advantage of being an Imperial age is multiple arithmetic
bases is not a problem. Younger metric people are base 10 only!

Not hardly, people don't think of 10 inches as 0.833 feet nor do
they think of 10 feet as 3.333 yards.


--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com

---
This email has been checked for viruses by AVG.
http://www.avg.com

On Sun, 2 Jul 2017 04:31:24 -0500, Foxs Mercantile
wrote:

On 7/2/2017 3:44 AM, Stephen Wolstenholme wrote:
The advantage of being an Imperial age is multiple arithmetic
bases is not a problem. Younger metric people are base 10 only!

Not hardly, people don't think of 10 inches as 0.833 feet nor do
they think of 10 feet as 3.333 yards.

I can work in any arithmetic base without converting from one to
another. I'm 68 years old and I was bought up and taught using
Imperial measures.

Steve

--
Neural Network Software for Windows http://www.npsnn.com

Foxs Mercantile wrote on 7/2/2017 5:31 AM:
On 7/2/2017 3:44 AM, Stephen Wolstenholme wrote:
The advantage of being an Imperial age is multiple arithmetic
bases is not a problem. Younger metric people are base 10 only!

Not hardly, people don't think of 10 inches as 0.833 feet nor do
they think of 10 feet as 3.333 yards.

What do they think of feet and yards? To me a yard is *about* a meter and a
foot is 0.3 meters.

--

Rick C

On Sun, 2 Jul 2017 04:31:24 -0500, Foxs Mercantile
wrote:

On 7/2/2017 3:44 AM, Stephen Wolstenholme wrote:
The advantage of being an Imperial age is multiple arithmetic
bases is not a problem. Younger metric people are base 10 only!

Not hardly, people don't think of 10 inches as 0.833 feet nor do
they think of 10 feet as 3.333 yards.

Wrong. You're creating more digits than was originally intended by
adding spurious significant figures. 10 inches has only two
significant figures. Therefo
10 in = 0.83 ft = 0.00016 miles = 0.57 Roman cubits
and so on.

For domestic consumption, I use US units. For scientific, I use
metric units. For political discussions (i.e. AGW) or when I want to
confuse the reader, I use SI units. When dealing with government
agencies, I use the same as what they prefer, which are usually units
of measure that have been aged for at least 100 years. For Usenet
discussions, I use a wide mixture of these, to insure that my
assertions and guessing cannot be verified.


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

Jeff Liebermann wrote on 7/2/2017 1:19 PM:
On Sun, 2 Jul 2017 04:31:24 -0500, Foxs Mercantile
wrote:

On 7/2/2017 3:44 AM, Stephen Wolstenholme wrote:
The advantage of being an Imperial age is multiple arithmetic
bases is not a problem. Younger metric people are base 10 only!

Not hardly, people don't think of 10 inches as 0.833 feet nor do
they think of 10 feet as 3.333 yards.

Wrong. You're creating more digits than was originally intended by
adding spurious significant figures. 10 inches has only two
significant figures. Therefo
10 in = 0.83 ft = 0.00016 miles = 0.57 Roman cubits
and so on.

I see you attended the same school as my chemistry lab professor.
"Significant digits" is an idea that is very dated and was only useful when
performing the simplest calculations like the ones we did on a slide rule.
The real issue is accuracy. I can measure 10 feet with an accuracy better
than a sixteenth of an inch (yeah, I said sixteenth because that's how my
tapes are marked off) and I will still note it as 10 feet.

When I perform calculations I want to preserve the accuracy of the result,
so the calculations are done with a higher degree of accuracy than the
initial data. How much more accuracy should be used depends on the extent
and nature of the calculations. One subtraction of large numbers can result
in a small number which does not have nearly as much accuracy as the initial
data. Add to that lack of accuracy with limited precision intermediate
representation and you can end up with pointless data.

I would also point out that in both cases the final digits repeat. There is
no way to show a vinculum in ascii so seeing repeating digits at the end of
a fraction is a clue. There is nothing wrong with specifying the conversion
exactly. 10 inches is 0.833 (vinculum implied but not shown). Leave it off
and you *add* to the initial error.

--

Rick C

On Sun, 2 Jul 2017 14:12:59 -0400, rickman wrote:

Jeff Liebermann wrote on 7/2/2017 1:19 PM:
On Sun, 2 Jul 2017 04:31:24 -0500, Foxs Mercantile
wrote:

On 7/2/2017 3:44 AM, Stephen Wolstenholme wrote:
The advantage of being an Imperial age is multiple arithmetic
bases is not a problem. Younger metric people are base 10 only!

Not hardly, people don't think of 10 inches as 0.833 feet nor do
they think of 10 feet as 3.333 yards.

Wrong. You're creating more digits than was originally intended by
adding spurious significant figures. 10 inches has only two
significant figures. Therefo
10 in = 0.83 ft = 0.00016 miles = 0.57 Roman cubits
and so on.

I see you attended the same school as my chemistry lab professor.

Probably. The standard lecture was to pace off some distance ending
up a bit short. One then measures the remaining distance to a much
higher degree of precision. Take the number of paces, multiply by 1
yard/pace, add the precision measured distance, and the sum is a
fairly useless number.

How accurate can the average tape measure wielding reader measure 10
inches? My guess(tm) is no more than ±0.05 inch.

"Significant digits" is an idea that is very dated and was only useful when
performing the simplest calculations like the ones we did on a slide rule.
The real issue is accuracy. I can measure 10 feet with an accuracy better
than a sixteenth of an inch (yeah, I said sixteenth because that's how my
tapes are marked off) and I will still note it as 10 feet.

If you use a tape measure to an accuracy better than ±1/16th of an
inch or 0.0625 inches, your actual distance would land somewhere
between 9.9375 and 10.0625. This does not mean that your tape measure
is accurate to 1/10,000th of an inch. To be accurate, one needs to
specify the measurement tolerances, as is common on all mechanical
drawings and an amazing number of schematics that still display
tolerances.

Using a steel rule, if you're able to measure the required 10 inches
to perhaps ±0.1 inches, then the correct representation would be 10.0
inches. 10 inches implies an accuracy of ±1 inch as measured by the
number of spans of my index finger between the first two joints.

When I perform calculations I want to preserve the accuracy of the result,
so the calculations are done with a higher degree of accuracy than the
initial data.

Argh. I sometimes see that in parts drawings. Some newly minted
mechanical designer grinds out every dimension to whatever number of
digits he has his calculator configured, and then doesn't bother
providing a usable tolerance. The result is the machine shop doesn't
know if they need to cut metal to ±1/10,000th of an inch, or something
less. Such excess precision tends to dramatically raise parts costs.
If you want to preserve your accuracy on your own design notes, that's
fine. Just don't submit those numbers to anyone that has to make or
price the part.

How much more accuracy should be used depends on the extent
and nature of the calculations.
One subtraction of large numbers can result
in a small number which does not have nearly as much accuracy as the initial
data. Add to that lack of accuracy with limited precision intermediate
representation and you can end up with pointless data.

Yep. That's roughly what I've been mumbling about.

I would also point out that in both cases the final digits repeat. There is
no way to show a vinculum in ascii so seeing repeating digits at the end of
a fraction is a clue. There is nothing wrong with specifying the conversion
exactly. 10 inches is 0.833 (vinculum implied but not shown). Leave it off
and you *add* to the initial error.

Very true. The convention is to round off anything that ends in 5 to
the next higher digit. So,
0.8333333333 will round off to 0.833 or 0.83 or 0.8
and:
0.8666666666 will round off to 0.867 or 0.87 or 0.9
If you have a tolerance available, writing 8.6666666666666666 ±0.001
would not make much sense. It should be written: 8.666 ±0.001 .




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

On Sunday, 2 July 2017 18:19:23 UTC+1, Jeff Liebermann wrote:
On Sun, 2 Jul 2017 04:31:24 -0500, Foxs Mercantile
wrote:
On 7/2/2017 3:44 AM, Stephen Wolstenholme wrote:

The advantage of being an Imperial age is multiple arithmetic
bases is not a problem. Younger metric people are base 10 only!

Not hardly, people don't think of 10 inches as 0.833 feet nor do
they think of 10 feet as 3.333 yards.

Wrong. You're creating more digits than was originally intended by
adding spurious significant figures. 10 inches has only two
significant figures. Therefo
10 in = 0.83 ft = 0.00016 miles = 0.57 Roman cubits
and so on.

For domestic consumption, I use US units. For scientific, I use
metric units. For political discussions (i.e. AGW) or when I want to
confuse the reader, I use SI units. When dealing with government
agencies, I use the same as what they prefer, which are usually units
of measure that have been aged for at least 100 years. For Usenet
discussions, I use a wide mixture of these, to insure that my
assertions and guessing cannot be verified.

Lol. Reminds me when I got criticised for mixing metric & imperial in a technical drawing. Widget A was normally supplied in imperial units, widget B in mm, so it was the sensible way to go. But bigco bs ruled, causing extra work to be done.


NT

On Sun, 2 Jul 2017 16:12:57 -0700 (PDT), wrote:

On Sunday, 2 July 2017 18:19:23 UTC+1, Jeff Liebermann wrote:
On Sun, 2 Jul 2017 04:31:24 -0500, Foxs Mercantile
wrote:
On 7/2/2017 3:44 AM, Stephen Wolstenholme wrote:

The advantage of being an Imperial age is multiple arithmetic
bases is not a problem. Younger metric people are base 10 only!

Not hardly, people don't think of 10 inches as 0.833 feet nor do
they think of 10 feet as 3.333 yards.

Wrong. You're creating more digits than was originally intended by
adding spurious significant figures. 10 inches has only two
significant figures. Therefo
10 in = 0.83 ft = 0.00016 miles = 0.57 Roman cubits
and so on.

For domestic consumption, I use US units. For scientific, I use
metric units. For political discussions (i.e. AGW) or when I want to
confuse the reader, I use SI units. When dealing with government
agencies, I use the same as what they prefer, which are usually units
of measure that have been aged for at least 100 years. For Usenet
discussions, I use a wide mixture of these, to insure that my
assertions and guessing cannot be verified.

Lol. Reminds me when I got criticised for mixing metric & imperial in
a technical drawing. Widget A was normally supplied in imperial
units, widget B in mm, so it was the sensible way to go. But
bigco bs ruled, causing extra work to be done.
NT

Chuckle. Sounds very familiar. I haven't mixed dimensions on a
technical drawing yet, mostly because I usually have someone else do
the work. However, a few months ago, I gave an ill prepared and short
notice talk on radiation measurement, where I managed to mix the older
conventional units of measure (Curie, Rad, and Rem) with the new and
not so improved SI units (Becquerel, Sievert, and Gray).
https://emergency.cdc.gov/radiation/measurement.asp
Audience confusion was averted by me having a conversion program
running on my tablet, where I was able to rapidly supply numbers in
both measurement system. I'm fairly functional in both systems, as is
evident by being able to make the same mistakes in both systems, but
forgot that others have their personal preferences.

Actually, there's a 3rd system of radiation measurement that I
fortunately didn't mention. Health physics uses electron volts (eV)
or sometimes joules to measure radiation dosage.

In my area of expertise, the RF industry has resisted pressure to name
units of measure after notable dead scientists and instead uses
fundamental units and ratios. It sometimes gets a bit complexicated,
such as RF field power, density, intensity, etc. I have a handy cheat
sheet available to keep me sane:
http://802.11junk.com/jeffl/coverage/VZW-water-plant/Field%20Intensity%20and%20Power%20Density.pdf
That audio industry does much of the same with various dB over some
reference level measurements (dB, dBm, dBw, dBC, dBA, dBi, dBu, dBmV,
dBV, dB/uV, dBrn, dB-SPL, dBrnC, etc). Mo
https://en.wikipedia.org/wiki/Decibel#Suffixes_and_reference_values


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

On 7/1/2017 8:14 PM, Jon Elson wrote:
wrote:

I needed to replace a 1/8" stereo plug on a cord. I found on ebay a pack
of three 1/8" stereo plugs from China, for about $2. I dont normally
order from China, but for the price and since I was in no hurry for
them, I bought them.

That was a mistake. They are NOT stereo, they are THREE CHANNEL. The tip
of the plug has THREE contacts, (plus the grounded base). What the heck
are they for? I have never seen any 3 prong 1/8" jacks on anything.
They are for cell phone headsets and other connections to a phone (like a
car). Left and right audio out, and microphone. Blame Apple.

Jon

I could be wrong, but I think I read somewhere that the Brits used to
use similar plugs for their (landline) phones. Think they called it,
"plug-and-jack (or -socket)?"

On Thursday, July 6, 2017 at 9:20:24 AM UTC-4, Madness wrote:

I could be wrong, but I think I read somewhere that the Brits used to
use similar plugs for their (landline) phones. Think they called it,
"plug-and-jack (or -socket)?"

Back in the day, Bell System phones were 4-wire, and all 4 had some function. Most of the world (back then) used 4 wires - Poland, apparently, used 5.

Peter Wieck
Melrose Park, PA

wrote on 7/6/2017 10:14 AM:
On Thursday, July 6, 2017 at 9:20:24 AM UTC-4, Madness wrote:

I could be wrong, but I think I read somewhere that the Brits used to
use similar plugs for their (landline) phones. Think they called it,
"plug-and-jack (or -socket)?"

Back in the day, Bell System phones were 4-wire, and all 4 had some function. Most of the world (back then) used 4 wires - Poland, apparently, used 5.

The Bell System used two wires for the phone line and if you had a Princess
phone the other two were used to supply power for the lighted dial.
Otherwise the other two were for your second extension line. This has
nothing to do with the four way plugs and jacks the OP is talking about.

--

Rick C

On Thursday, July 6, 2017 at 10:30:43 AM UTC-4, rickman wrote:

The Bell System used two wires for the phone line and if you had a Princess
phone the other two were used to supply power for the lighted dial.
Otherwise the other two were for your second extension line. This has
nothing to do with the four way plugs and jacks the OP is talking about.

Bell System:

Up to 1930 - three active wires: Voice/Ringer/Ground
From 1930 well into the 1960s, up until touch-tone *in some regions* and with some providers: Four active wires: Voice/Ringer/Side-Tone Suppression/Ground

At some point, the side-tone suppression function was served by a small capacitor - this took a few years to become universal. A diode allowed all functions to be handled by only two wires. After which the additional wires could serve such niceties as lighting. BUT - those functions required a local wall-wart type power-supply feeding a jack for proper distribution.

Peter Wieck
Melrose Park, PA

Hello!

Â*Â*Â*Â* I know this is besides the point, but I've got a unit conversion app that I'm releasing a new version of, and I thought I'd see if people around here would like to test it.

Â*Â*Â*Â* You can convert units and ratios.

Â*Â*Â*Â* You can convert two units at a time.

Â*Â*Â*Â* You can use fractions.

Â*Â*Â*Â* You have more units than you can shake a stick at (but don't, it make them mad).

Â*Â*Â*Â* So, if anyone wants it's he https://play.google..com/apps/testin...nversion_A pp