I swear the wires my youngin has run in his car has to be 2-0 just
feeding his ^&*%* darn boom box............me I use zip cord or
whatever else I sufficient quanities of, half deaf anyhow so it makes
no difference to me
WINDSONG......the ability to play musical tunes by farting!
This is worth repeating for benefit of al newbies!
Jo Ann asked Dr. Solo to remind people that while she has retired from selling
GF (and sold
the business to Ken Fischer http://dandyorandas.com /) she has NOT retired from
helping people with sick GF and koi FOR FREE. 251-649-4790 phoning is best for
diagnosis. but, can try email put "help sick fish" in subject. Get your fish at
Dandy Orandas
Dandy Orandas Dandy Orandas........you guys got that DANDY ORANDAS
You should check the "hi fi" that you will be using as some of the older
ones (that I used)
didn't like to see a long run to the speaker. It was some problem with
inductance or something
I don't remember the details. Otherwise you should have no problem.
Bill K7NOM
Even if you are, you won't know the difference. Time domain
reflectometry comparison between Monster Cable and #14 zip cord showed
no difference in signal quality in a band from 0 to 100MHz.
I don't know about _your_ ears, but mine don't go quite that high...
The point about solid wire looking like power wiring is valid, though.
As low voltage cable, it'd have to be in different junction boxes and so
on. Something to consider - if you run that blue flexible conduit ('Smurf
tubing' I've heard it called), then you can always pull new cables in as
technology and your needs change. That's the one thing I didn't do when
I built my house, that I regret not doing.
Dave Hinz
Heh...I've saved a ton of money over the decades by not being able to
hear that alleged last 5% of sound quality improvement that makes
something 10 times more expensive.
As soon as you can put "believability" into engineering terms I can
measure, I'll be happy to measure it. I used to work with a guy who
was an freak amongst audiophiles - granite turntable, magnapan speakers,
tube amps, cables the size of your arm, and all that. Yeah, sure, it
sounded good, but...the Bose system for a few hundred bucks sounds
pretty damn good too, y'know?
I missed the staff meeting but the minutes show Dave Hinz
rec.crafts.metalworking :
Umpty eleven years ago, I went with my Dad to buy a stereo. Went to
Japan, and I doubled his "duty free" amount. [Hmmm - half that stereo was
mine.] He'd been talking to the audiophiles, and they basically told him
"if you got a hundred dollar ear, buy the hundred dollar stereo. If you
have the fifty dollar year, buy the fifty dollar stereo." (Tells you hold
long ago this was).
His response was "I've got a ten dollar ear ..."
So I got a week in Japan with my Dad, as he shopped around. Lots of
fun for a twelve year old kid.
tschus
pyotr
--
pyotr filipivich.
as an explaination for the decline in the US's tech edge, James
Ah but Ted. You should know more than anyone that TDR
measurements won't show the real effect taht true audiophools
can hear. Their ears are so much more sensitive than those
instruments.
How else could they justify buying those gold-plated power
connectors?
Jim
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please reply to:
Jim,
Just goes to show ya how much you know. Ted probably knows how to build a
TDR that'll show minute differences in the gold plating.
Bob Swinney
Ted Edwards says...
I do know that all gold-plating is not the same. Trompeter
(the connector guys) understand that you cannot strike with
nickel first under the gold, like many folks do.
You actually can see the distortion from that.
Jim
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please reply to:
a
That's an interesting observation. If you don't know, the reason the
nickel is plated to begin with is to prevent migration of the gold to the
base metal. In my years of refining I discovered it was pretty much common
practice to find nickel under gold plating when stripping. Sir T.K. Rose
concluded long ago that gold and silver have an affinity for certain metals
and will migrate to them when in close proximity, and they need not be
molten or even hot. Ingots of pure silver and pure gold end up
transferring to one another when in contact, for example. Nickel prevents
the migration. If what you say is correct, unless gold is plated quite
thick (I have no idea what that may mean) , there is likely no benefit in
using it at all, because, over time, and it's not long, it simply vanishes.
One problem gets replaced with another. Comments?
Harold
Transition metals are commonly used as both diffusion barriers and
as adhesion layers. (Ti, Ni, Mo, W, etc)
The first prevents the plated, or deposited, layer from diffussing into
the the substrate. This is a real issue in semiconductor processing,
where it's important to keep layers of metal (wiring) on chips from
being contaminated by the layers adjacent. This is especially important
because some of the processing is carried out at elevated temperatures.
A layer of, say, Ti, that is about 200 atomic layers thick will
suffice to keep the layers of the cake from smearing out.
Adhesion layers are another issue. This is why nickel strikes are
used under gold plating as a rule.
Adhesion is a peculiar thing - what makes one thing 'stick' to another?
At atomic levels this question is a) of considerable practical interest
and b) not entirely well understood. There's a lot of research being
done on the fundamentals.
I can recall desperately trying to figure out some way to deposit
copper on sapphire stubstrates - but it would *not* stick. The
common trick is to put down a Ni adhesion layer, but nickel is magnetic
and for our work that was unacceptable.
That company I mentioned (trompeter) makes rf connectors for low
level, high freqency applications. All of the other connectors
I investigated were magnetic because of the ni strike in the plating
process. Because they build for the small-signal rf market - mostly
satallite communications gear - they understand that distortion of
the rf signal can occur from any magnetic materials in the connector,
so they use something they call a "pulse plating" process to
eliminate the Ni strike beforehand. This is specifically to
replace an *adhesion* layer, not a diffusion barrier.
Does the gold diffuse through into the brass metal underneath?
I honestly don't know. They may use some other kind of diffusion
barrier, but I've never seen them degrade over the 20 or so years
I've been using them. I will look up in their catalog at work
and find their spec for plating thickness.
Jim
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please reply to:
common
Rose
metals
prevents
vanishes.
Yeah, and I've seen a few examples of it through the years, but just a few,
obviously something that was done rarely. Almost everything I processed
with cyanide had nickel underneath. Without the nickel strike, the gold
layer would start oxidizing, but only because it had been absorbed by the
base metal. As you well know, it's not lost, but is no longer providing a
barriers because it has diffused too much, leaving the base metal
unprotected, and it's the base metal oxidizing, not the gold. The gold is
recovered in refining, assuming you dissolve the base metal, not strip it,
so long as nothing is discarded. I found that by filtering with a well
clogged filter, or allowing the solution to settle well before decanting, I
would end up with the gold, although it certainly didn't look like gold at
that point. When the base metal is dissolved, the gold, for all practical
purposes is down to what might be considered a colloid, (go easy on me here,
Jim, I'm not a chemist) perhaps? Very finely divided particles, clusters
of atoms, nothing you can really see, but you do see the affect, a purple
color. Various processes before dissolving the gold allow complete
recovery.
That varies according to need, and one pays accordingly. I supplied a
modified connector to Univac on several occasions, where four were made from
one, a Cinch wire wrap connector. This was prior to May of '83, when I
closed the doors on my shop permanently. I purchased them directly from
the mfg. and modified them to Univac's specs. They specified a given
depth of plating, under a tenth, 80 millionths as I recall, but one had
options as need required. At least that's the way I remember it. It was
interesting to see the pricing schedule and gold adder, considering I was
machining at the same time I was refining and by then had a firm
understanding of the amount of gold in question. Need I tell you the
price of the gold adder was quite lucrative for the manufacturer?
I did have one very interesting experience, the opportunity to strip some
micro-wave gear that hailed from what must have been WW II equipment. The
plating on it was so heavy that it was in thousandths, not millionths.
There was no barrier under it, which made stripping with cyanide very
difficult because there was nothing to prevent the base metal from
dissolving along with the gold (done electrolytically). Nickel does just
that. Some of this gear was one of the rare times I recall seeing gold
oxidize, but only one part in particular. It was a brass casting (wave
guide? dunno!) that was heavily plated, but still managed, some areas much
worse than others. The gold had obviously been absorbed. A sulfuric
process would have been far better suited to stripping that stuff. It
doesn't attack the copper base, but removes the gold quickly. I would have
to wonder if the diffused gold would have been recovered, though.
Harold
Trompeter makes a lot of their stuff on my machines.
So does Maury Microwave
http://www.maurymw.com/aboutus/planttour/machine/mach26.jpg
Gunner
It's better to be a red person in a blue state
than a blue person in a red state. As a red
person, if your blue neighbors turn into a mob
at least you have a gun to protect yourself.
As a blue person, your only hope is to appease
the red mob with herbal tea and marinated tofu.
(Phil Garding)
Jim, I sincerely hope that you don't seriously expect to see any
distortion at audio frequencies resulting from the plated layers found
in connectors.
Maybe at X-band but ...
Ted
Those were microwave connectors Ted. The distortion winds up
as intermodulation products, trompeter makes so many different
kinds of connectors I think they just decided to make their
plating standards for gold avoid nickel for *all* their connectors.
For me this was good because I had to obtain miniature triax
connectors with very low remanent magnetization.
They were the only folks I found who could do this.
Jim
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please reply to:
FYI this intermod effect was noticed with a 100 Watt 450 MHz transmitter
which
was connected to an antenna that was also used for receiving (with a
diplexer)
Replace the connectors with Silver and all was OK.
Bill K7NOM
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