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Intresting Engine

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beel@network.com Howard Beel

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Aug 14, 2016, 11:44:50 PM8/14/16
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Jon Elson

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Aug 15, 2016, 4:52:37 PM8/15/16
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Hmm, my 2009 Honda Civic hybrid has variable intake valve timing, which
seems to pretty much accomplish the same thing. They've been doing this for
some time, probably dates back to at least 2006 on that model.

By reducing the charge drawn into the cylinders, it reduces the peak
pressure, so that seems to be varying the compression, too.
A pretty low-tech way to accomplish it, it doesn't make any chages to the
lower end. This Infiniti scheme seems to add a LOT more complexity to the
lower end. I wonder if this is some way to get around a Honda patent?

Jon

Jim Wilkins

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Aug 15, 2016, 5:34:09 PM8/15/16
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"Jon Elson" <jme...@wustl.edu> wrote in message
news:I8idnR-4OaITti_K...@giganews.com...
Or a Peugeot patent?
http://www.motortrend.com/news/mce5-to-debut-220hp-15l-engine-with-variable-compression-ratio-at-geneva-3891/
--jsw


Ed Huntress

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Aug 15, 2016, 5:48:22 PM8/15/16
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On Mon, 15 Aug 2016 15:53:20 -0500, Jon Elson <jme...@wustl.edu>
wrote:
I think you're misreading it, Jon. This engine is truly revolutionary.
Varying valve timing as you describe just produces a pseudo-Atkinson
cycle, used on today's hybrids:

https://en.wikipedia.org/wiki/Atkinson_cycle

What this new Nissan engine does is to actually change the compression
ratio of the engine.

The nominal compression ratio of an ordinary engine (say, 10:1) is
only achieved at full-throttle operation. At any other condition, the
actual compression ratio is less, because less air-gas is let in. This
is the chief reason that gasoline engines can't achieve the efficiency
of diesels, which are always running at their nominal compression
ratio.

If you can vary the compression ratio, you can approach the nominal
ratio even at part-throttle operation. To achieve it, you actually
have to increase the ratio *above* the nominal amount (say, to 14:1).
When you do that, the part-throttle operation, which lets in less
air-gas, causes the *actual* compression ratio, or effective
compression ratio, to be returned to the optimum 10:1. (These values
are just examples.)

You wind up with diesel-like efficiency. Then, the Atkinson cycle
extracts more, by effectively extending the expansion stroke.

The Atikinson-cycle part of the operation is incidental to the
variable compression ratio. It's the variable compression ratio that's
the big deal. A true Atkinson cycle is quite efficient, but the pseudo
Atkinson cycle of today's hybrids is less so.

--
Ed Huntress

Carl Ijames

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Aug 15, 2016, 10:27:12 PM8/15/16
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"Ed Huntress" wrote in message
news:k8d4rb9pi9hen9du0...@4ax.com...
Ed Huntress
===================================================================

Saab demonstrated a running variable compression supercharged 5 cylinder in
2000, see https://en.wikipedia.org/wiki/Saab_Variable_Compression_engine for
example. Naturally GM killed it sometime after they acquired Saab, citing
cost. This was an inline engine with the block split horizontally between
crankshaft and cylinders, with a hinge down one side and a mechanism to lift
the other side to control the compression.

-----
Regards,
Carl Ijames


Jon Elson

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Aug 16, 2016, 4:04:52 PM8/16/16
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Ed Huntress wrote:

> On Mon, 15 Aug 2016 15:53:20 -0500, Jon Elson <jme...@wustl.edu>
> wrote:
>

> I think you're misreading it, Jon. This engine is truly revolutionary.
> Varying valve timing as you describe just produces a pseudo-Atkinson
> cycle, used on today's hybrids:
>
Right.

>
> What this new Nissan engine does is to actually change the compression
> ratio of the engine.
>
> The nominal compression ratio of an ordinary engine (say, 10:1) is
> only achieved at full-throttle operation. At any other condition, the
> actual compression ratio is less, because less air-gas is let in. This
> is the chief reason that gasoline engines can't achieve the efficiency
> of diesels, which are always running at their nominal compression
> ratio.
>
Well, getting rid of pumping loss is a really good thing, so maybe this
accomplishes the variable output without a throttle, at least under the
driving range of operation (might still be needed for idle).
> If you can vary the compression ratio, you can approach the nominal
> ratio even at part-throttle operation. To achieve it, you actually
> have to increase the ratio *above* the nominal amount (say, to 14:1).
> When you do that, the part-throttle operation, which lets in less
> air-gas, causes the *actual* compression ratio, or effective
> compression ratio, to be returned to the optimum 10:1. (These values
> are just examples.)
>
> You wind up with diesel-like efficiency. Then, the Atkinson cycle
> extracts more, by effectively extending the expansion stroke.
>
> The Atikinson-cycle part of the operation is incidental to the
> variable compression ratio. It's the variable compression ratio that's
> the big deal. A true Atkinson cycle is quite efficient, but the pseudo
> Atkinson cycle of today's hybrids is less so.
>
OK, that probably requires a degree in thermodynamics to understand.

Jon

Cydrome Leader

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Aug 16, 2016, 4:29:45 PM8/16/16
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Ed Huntress <hunt...@optonline.net> wrote:
> On Mon, 15 Aug 2016 15:53:20 -0500, Jon Elson <jme...@wustl.edu>
> wrote:
>
>>Howard Beel wrote:
>>
>>> New engine to hit the market in 2017.
>>>
>>>
>>>
>>> http://www.autoblog.com/2016/08/14/infiniti-vc-t-engine-variable-
>>compression-official/
>>>
>>>
>>> Best Regards
>>> Tom.
>>Hmm, my 2009 Honda Civic hybrid has variable intake valve timing, which
>>seems to pretty much accomplish the same thing. They've been doing this for
>>some time, probably dates back to at least 2006 on that model.
>>
>>By reducing the charge drawn into the cylinders, it reduces the peak
>>pressure, so that seems to be varying the compression, too.
>>A pretty low-tech way to accomplish it, it doesn't make any chages to the
>>lower end. This Infiniti scheme seems to add a LOT more complexity to the
>>lower end. I wonder if this is some way to get around a Honda patent?
>>
>>Jon
>
> I think you're misreading it, Jon. This engine is truly revolutionary.
> Varying valve timing as you describe just produces a pseudo-Atkinson
> cycle, used on today's hybrids:
>
> https://en.wikipedia.org/wiki/Atkinson_cycle

I like the old-timey bizarre mechanical linkages used to acheive the weird
motions folks used to really get excited over.

Lloyd E. Sponenburgh

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Aug 16, 2016, 4:50:49 PM8/16/16
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Cydrome Leader <pres...@MUNGEpanix.com> fired this volley in
news:novt3m$7u2$1...@reader2.panix.com:

> I like the old-timey bizarre mechanical linkages used to acheive the
> weird motions folks used to really get excited over.

They're hardly "bizarr". I use such linkages on my machines to make
explosive materials. Those 'bizarre' linkages are really a basic part of
mechanics.

Look at some of the OLD (say, pre-1960s), purely-mechanical manuals on how
to achieve various motions -- it's all in there!

Lloyd

Ed Huntress

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Aug 16, 2016, 4:53:51 PM8/16/16
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On Tue, 16 Aug 2016 15:05:36 -0500, Jon Elson <jme...@wustl.edu>
Let me try the simple version and see if I can be clear: It is a
thermodynamics issue. The higher the compression ratio, the greater is
the Carnot efficiency of an engine. You don't need a thermodynamics
background to get the idea of the Carnot cycle and efficiency.
Wikipedia probably does it.

This is the main reason why diesels are so efficient: they always run
at full, nominal compression. There is no throttle on the air. It's
only the fuel that's varied as you advance from idle to full throttle.

On a spark-ignition engine, you keep the fuel/air mix as close to
uniform as you can, and you vary the amount of the mix that gets into
the cylinder, with the throttle. If you vary the fuel/air ratio by
much (the ideal is 14.7 pounds of air for a pound of gasoline), the
mixture won't ignite with a spark. So at full throttle, the engine
will be running at a high compression ratio, the nominal ratio --
maybe 10:1 for example. At part throttle, the lesser amount of
fuel/air mix produces a much lower effective compression ratio --
maybe 5:1 at some throttle settings. The Carnot efficiency goes to
hell.

So you can see why having a variable compession ratio is such a big
deal. Manufacturers have been trying to produce a variable compression
ratio system that works well and that doesn't cost an arm and a leg,
for close to a century.

The Atkinson cycle is something completely different, but it's another
thermodynamics issue. I'll give it a try:

The true, original Atkinson cycle involved a short intake and
compression stroke, and a long expansion stroke and exhaust stroke. A
true Atkinson did it by means of a complex crank mechanism. The
"pseudo Atkinsons," like the engines in today's hybrids, have the
same-length stroke for all four parts of the cycle. But they open the
intake valve late so the cylinder is less-filled. The expansion
stroke, therefore, is *relatively* long for the amount of fuel being
burned. You get more efficiency because the charge expands to a
greater degree than normal. The nominal compression ratio is very
high, but the *actual* compression is normal, because of the lesser
cylinder-filling.

This Nissan engine combines both, but it's the compression ratio
that's the big deal.

Tell me if this is as clear as mud. <g>

--
Ed Huntress

Ed Huntress

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Aug 16, 2016, 4:56:17 PM8/16/16
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Some of those are still around. This engine's crank is pretty wild.
And some high-performance Stirlings use a rhombic-drive crank.

--
Ed Huntress

Jim Wilkins

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Aug 16, 2016, 6:25:19 PM8/16/16
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"Jon Elson" <jme...@wustl.edu> wrote in message
news:4smdnVQQu5pB7C7K...@giganews.com...
Engine efficiency increases with higher combustion ratio, limited by
preignition and Knock.
https://en.wikipedia.org/wiki/Engine_knocking

Knock varies with combustion conditions and can be sensed with a
microphone sharply tuned to the block's resonant frequency (thus
filtering out other sounds) and controlled by backing off the spark
advance until it nearly disappears. The old vacuum advance did this
open-loop, advancing the spark further at light throttle when intake
vacuum is high and releasing it back to the RPM-controlled centrifugal
advance position when you floor the pedal. However this is the easy
but not the best way.

SAAB's conceptually simple system moves the cylinder block up or down
relative to the crankshaft and piston to vary the combustion chamber's
size to maintain maximum allowable pressure and the best efficiency at
any power demand.
http://www.autozine.org/technical_school/engine/tech_engine_4.htm
Look at the positions of the orange eccentric shaft to the right of
the connecting rod, and the red combustion chamber.

--jsw


Cydrome Leader

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Aug 16, 2016, 6:33:47 PM8/16/16
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It also turns out lots of those motions just aren't necessary. On another
group there was chat about VHS tape recorders. Granted most machines now
have some level of computer in them and mechanical timing stuff isn't
needed anymore. The bottom line is cheap, not let's make elegant
mechanisms anymore.

Back to VCRs, the original ones had like a half dozen motors. Recent ones,
say made in the past 15-20 years were down to like 2 motors.

They designed all the complex mechanical nonsense out of the product. As
it turns out, none of that complexity was really needed in the first
place.




Lloyd E. Sponenburgh

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Aug 16, 2016, 8:16:27 PM8/16/16
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Cydrome Leader <pres...@MUNGEpanix.com> fired this volley in news:np04c9
$rtk$1...@reader2.panix.com:

> They designed all the complex mechanical nonsense out of the product. As
> it turns out, none of that complexity was really needed in the first
> place.
>

But, "complexity" is not a part of an elegant mechanical design! Folks
design stuff based on their "art" at the time. Elegance in mechanics
peaked about 1930... It has gone down-hill ever since.<urk!>

Lloyd

Larry Jaques

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Aug 16, 2016, 8:46:12 PM8/16/16
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Here's a lovely tome into which one can get themself nicely lost:
http://tinyurl.com/hh2sdge 1800 Mechanical Movements...

--
I believe there are more instances of the abridgment of the
freedom of the people by gradual and silent encroachment of
those in power than by violent and sudden usurpations.
--James Madison

Lloyd E. Sponenburgh

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Aug 16, 2016, 10:16:00 PM8/16/16
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Larry Jaques <lja...@invalid.diversifycomm.com> fired this volley in
news:boc7rb9cq3aafq4ia...@4ax.com:

> Here's a lovely tome into which one can get themself nicely lost:
> http://tinyurl.com/hh2sdge 1800 Mechanical Movements...
>

I have the four-volume set of "Ingenious mechanisms for designers and
inventors". It's just FULL of good stuff, some (small amount) of which
I've employed on my machines for the miltary.

Lloyd

Larry Jaques

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Aug 16, 2016, 11:17:24 PM8/16/16
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I just saw one copy of the set on Amazon for $750, while individual
volumes start at $0.54 used. <g> They sound like fun. I recently
picked up Practical Electronics for Inventors but haven't gotten to it
yet. At the end of this month (I'm retiring earlier) I'll have more
time to finish my hefty 'unread' bookshelf. Maybe even turn off
Kindle Unlimited again for awhile...


The use of ancient mechanisms in new military machinery is wildly
amusing to me. Physics doesn't change (much), and being able to use
old inventor's mechanisms in new ways is a great idea. Kudos.

I've also been buying and using vintage machinery all my life because
the old stuff is well designed and much cheaper than the new, while
being perfectly good for my uses. Granted, a $12k sliding table saw
makes a slightly better cut (0.1 RCH)than an old 10" cast iron jobber
(followed me home from Gunner's) but it also costs $12k more and would
take up over half my shop.

(Yeah, I know I got off-thread here with "vintage", but, just sayin'.)

--
The great thing about getting older is that
you don't lose all the other ages you've been.
-- Madeleine L'Engle

Cydrome Leader

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Aug 16, 2016, 11:50:15 PM8/16/16
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Lloyd E. Sponenburgh <lloydspinsidemindspring.com> wrote:
I'm sure lost of this knowledge has been lost. For a long time now I've
wondered how much effort it would take to design and built one of those
giant mechanical calculators like banks used to have. Those things were
absulutely insane in how complex they were and how many parts were crammed
inside.

Even typewritters are works of art in how the actions feel nice in
operation.

a $50 VCR is pretty amazing as well, when compared to an old one side by
side. If you consider them black boxes, the new throw away ones do still
work better. It's amazing how the the advancements in electronics rendered
all the other mechanical parts useless.

Gunner Asch

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Aug 17, 2016, 12:23:26 AM8/17/16
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On Tue, 16 Aug 2016 20:17:29 -0700, Larry Jaques
<lja...@invalid.diversifycomm.com> wrote:

>Granted, a $12k sliding table saw
>makes a slightly better cut (0.1 RCH)than an old 10" cast iron jobber
>(followed me home from Gunner's) but it also costs $12k more and would
>take up over half my shop.

Does the saw do what you want it to do? If not..bring it back.

(Grin)

Gunner

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

Steve W.

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Aug 17, 2016, 6:17:45 AM8/17/16
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You visit VintageMachinery.org.....
lot of kindred spirits who use "vintage" machines...

Oh for a .pdf of the 1800 movements book...
http://www.pdfarchive.info/pdf/H/Hi/Hiscox_Gardner_Dexter_-_1800_Mechanical_movements.pdf

--
Steve W.

Howard Beal

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Aug 17, 2016, 8:03:35 AM8/17/16
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"Steve W." <csr...@NOTyahoo.com> wrote in message
news:np1dk6$fcl$1...@dont-email.me...

> You visit VintageMachinery.org.....
> lot of kindred spirits who use "vintage" machines...
>
> Oh for a .pdf of the 1800 movements book...
> http://www.pdfarchive.info/pdf/H/Hi/Hiscox_Gardner_Dexter_-_1800_Mechanical_movements.pdf
>
> --
> Steve W.

This vintage 1909 engine stood the test of time. Love all cams and levers.
Still fires up today.

https://www.youtube.com/watch?v=WXzSZVgQwts

Best Regards
Tom.


Jim Wilkins

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Aug 17, 2016, 8:10:12 AM8/17/16
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"Cydrome Leader" <pres...@MUNGEpanix.com> wrote in message
news:np0mtl$q6i$1...@reader2.panix.com...
More specifically the advance in cheap computing power obsoleted both
mechanical control mechanisms and bulky discrete electronics such as
in older televisions. When I was learning communications electronics
in the Army in 1970 a phone line modem was the size of a 2-drawer file
cabinet. Each circuit card held two discrete transistor NAND gates.
The frequency shift modulator and demodulator were cleverly tuned
transformer / filter circuits that the instructor didn't understand.
They showed us evaluation samples of integrated circuit electronics
but we learned to repair the 1960's gear that was in wide use.

In the early 80's I built a similar frequency-shift modem the size of
a portable cassette recorder with parts from Radio Shack. The modem
and recorder were the mass storage for my home-brew computer.

As soon as fast enough analog to digital converters became affordable,
around 1990, a microcomputer could replace the remaining analog
circuitry. That enabled the digital radios I prototyped at Mitre, and
pocket-sized cell phones. The best A/Ds we could get back then were
for the new Tektronix and HP digital oscilloscopes.

On the other hand, when I was working on the color ink jet printer in
the mid 80's I halved the complexity of the electronics by a simple
mechanical rearrangement of the print head geometry.

The Army had the technology for encrypted voice and data cell phones
by 1970. The field-deployable electronics at the "cell tower" filled
six interconnected trailer trucks plus a van for the microwave radio
link, with a large Diesel generator on a trailer and at least two
dozen men and a field kitchen to support it all. We would have been a
tempting and easy target for Spetsnaz desantniki (paratroop
commandos).

--jsw


Jim Wilkins

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Aug 17, 2016, 8:49:16 AM8/17/16
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"Steve W." <csr...@NOTyahoo.com> wrote in message
news:np1dk6$fcl$1...@dont-email.me...
This is the tricky mechanism to learn:
https://en.wikipedia.org/wiki/Four-bar_linkage

I used it on my hydraulic loader to allow the bucket to drop to 30
degrees from vertical when fully raised, to dump sticky wet snow.
http://www.tractorbynet.com/forums/attachments/87123-fel-bucket-attachment.html

--jsw


Lloyd E. Sponenburgh

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Aug 17, 2016, 10:54:26 AM8/17/16
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"Jim Wilkins" <murat...@gmail.com> fired this volley in news:np1k70$4lj$1
@dont-email.me:

> The Army had the technology for encrypted voice and data cell phones
> by 1970.

We were running crypto'd voice in 1968 on Navy River Boats, over in 'Nam;
and I think they'd been using them for several years by the time I got
there.

The unit was about the size of a medium-sized benchtop oscilloscope (like a
Tek 525). We changed the 'Cac' code every day, as part of our pre-mission
checkouts.

Lloyd

Jim Wilkins

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Aug 17, 2016, 1:18:54 PM8/17/16
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message
news:XnsA6676EF1333E2ll...@216.168.4.170...
http://cryptomuseum.com/crypto/usa/index.htm

Tactical crypto machines were smaller, lighter and less secure, since
your comms about your mission became 'stale' and useless to ambush you
once you returned to base. The good stuff, the KG-13 and KY-3, weighed
several hundred pounds.

We were safeguarding Army payroll data, which sounds silly until you
realize that -where- troops were paid was important, not how much they
made. For example Putin would really like to know if US tank
commanders started receiving their pay in Ukraine.

The Navy had a very serious leak back then:
https://news.usni.org/2014/09/02/john-walker-spy-ring-u-s-navys-biggest-betrayal

--ave52G


Lloyd E. Sponenburgh

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Aug 17, 2016, 1:29:41 PM8/17/16
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"Jim Wilkins" <murat...@gmail.com> fired this volley in news:np269q$3h8$1
@dont-email.me:

> http://cryptomuseum.com/crypto/usa/index.htm

The KW-7 looks darned familiar! I think that was the one we had on the
boats.

Lloyd

Jim Wilkins

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Aug 17, 2016, 1:51:47 PM8/17/16
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message
news:XnsA6678943E73F5ll...@216.168.4.170...
It was meant to be used with a Teletype.



Jon Elson

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Aug 17, 2016, 3:03:42 PM8/17/16
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Ed Huntress wrote:

The
> "pseudo Atkinsons," like the engines in today's hybrids, have the
> same-length stroke for all four parts of the cycle. But they open the
> intake valve late so the cylinder is less-filled.
My only quibble is that the trick, at least on the Honda, is this also means
the intake valve CLOSES late, allowing some of the charge to be pushed back
into the intake manifold. So, the compression stroke starts with the piston
part way up the cylinder. This ends up with pretty low compression (or
cylinder pressure, if you prefer) at ignition.

I'm guessing the trick in the Nissan engine is they effectively reduce
displacement while still achieving a good cylinder pressure at low
horsepower settings. That ought to improve efficiency.

Jon

Ed Huntress

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Aug 17, 2016, 3:11:37 PM8/17/16
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On Wed, 17 Aug 2016 14:04:28 -0500, Jon Elson <jme...@wustl.edu>
wrote:
I've never paid much attention to Atkinson engines, so I don't know
what Honda is doing. BTW, the reason usually stated for *not* using
the Atkinson cycle in regular engines is that they're not very
tractable. I have read that they're slow to respond to the throttle,
but beyond that, I don't have a clue.

There must be a lot going on with the Nissan engine, combining the
turbocharger, the variable compression, and the Arkinson cycle. They
may have published a paper on it with SAE. That's where you get the
details.

--
Ed Huntress

Lloyd E. Sponenburgh

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Aug 17, 2016, 3:11:39 PM8/17/16
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"Jim Wilkins" <murat...@gmail.com> fired this volley in news:np287g$a6q$1
@dont-email.me:

> It was meant to be used with a Teletype.

Well, then, that wasn't the one <grin>. Ours was voice.

Lloyd

Larry Jaques

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Aug 17, 2016, 3:20:48 PM8/17/16
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On Tue, 16 Aug 2016 21:18:14 -0700, Gunner Asch <gunne...@gmail.com>
wrote:

>
>On Tue, 16 Aug 2016 20:17:29 -0700, Larry Jaques
><lja...@invalid.diversifycomm.com> wrote:
>
>>Granted, a $12k sliding table saw
>>makes a slightly better cut (0.1 RCH)than an old 10" cast iron jobber
>>(followed me home from Gunner's) but it also costs $12k more and would
>>take up over half my shop.
>
>Does the saw do what you want it to do? If not..bring it back.
>
>(Grin)

A $12k more expensive saw makes a "slightly better cut" and you think
I want to get rid of my new used saw which I haven't yet assembled?
OK, I'll go out back and lob it in your direction. It might miss
your yard by 623 miles, but...

I wish I had it together right now. I have to build a cabinet door
for a client. A local cabinetmaker wanted $400 to do one for me. I
asked him why he thought $25 worth of wood and an hour of his time
would be worth that. It'll take me considerably longer because I
don't have his shapers and spray booth, but I'll do a hand rubbed oil
finish instead. In the interim, I'll rip with the Makita SP6000J and
route with the rail and stile set from HF. Both make very decent
cuts. http://tinyurl.com/hacsqwe and http://tinyurl.com/hlg4sto

In 2 weeks, when I retire, I'm going to start getting a usable shop
back together and add a few dozen feet more shelf space. Then maybe
I'll be able to see floor in there again. <sigh>

I can't wait!

Jon Elson

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Aug 17, 2016, 5:43:01 PM8/17/16
to
Ed Huntress wrote:


> I've never paid much attention to Atkinson engines, so I don't know
> what Honda is doing. BTW, the reason usually stated for *not* using
> the Atkinson cycle in regular engines is that they're not very
> tractable. I have read that they're slow to respond to the throttle,
> but beyond that, I don't have a clue.
>
The only reason they'd be slow to respond is if the mechanism that changes
the valve timing is slow. I'm sure this is true in the Honda hybrid engine.
They put a rotary hydraulic cylinder in the intake cam sprocket, and I'm
guessing the control valve on that has a small orifice so that the computer
can keep up with the change in valve timing. I assume it has some sensor on
the cam so it can measure the valve timing every cam revolution. So, it
probably takes a dozen cam revolutions to make a large change in timing.

I can't imagine any other reason why it would be all that slow to respond.
If there was some kind of immediate angle sensor in the sprocket so the
computer had instant feedback of the valve timing, it could probably respond
a lot faster. The hybrid system masks this, you can even see it on the
battery gauge. Any time you push down on the gas pedal, the hybrid system
applies power until the ICE ramps power up, the revers if you ease up on the
pedal. it only takes 1/4 to 1/2 second to respond.
> There must be a lot going on with the Nissan engine, combining the
> turbocharger, the variable compression, and the Arkinson cycle. They
> may have published a paper on it with SAE. That's where you get the
> details.
>
Yup, sounds like a lot to manage.

Jon

Jon Elson

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Aug 17, 2016, 5:44:02 PM8/17/16
to
wrote:
Yes, KW is ciphered teleprinter, KY is ciphered voice.

Jon

Ed Huntress

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Aug 17, 2016, 5:48:27 PM8/17/16
to
On Wed, 17 Aug 2016 16:43:46 -0500, Jon Elson <jme...@wustl.edu>
wrote:
I see that Nissan published several papers on the development of this
engine, but the last one I saw was from 2006. I just read the
abstract.

--
Ed Huntress

Garrett Fulton

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Aug 17, 2016, 10:04:26 PM8/17/16
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Is this similar to the control head? http://ciphermachines.com/Gallery/index.php/voice/US-KY-28-Voice-Scrambler
That was the only voice scrambler I saw used on Marine aircraft in Vietnam. I figured the Navy used the same one but maybe the river boats were different? Had to change the codes at midnight every night. Code books were locked in a safe with two thermite grenades inside. If we got overrun, were supposed to set the grenades on top of the safe and set them off.

Garrett

Lloyd E. Sponenburgh

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Aug 18, 2016, 6:55:40 AM8/18/16
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Garrett Fulton <lbfu...@windstream.net> fired this volley in
news:94e546b6-87de-4d13...@googlegroups.com:

> Is this similar to the control head?
> http://ciphermachines.com/Gallery/index.php/voice/US-KY-28-Voice-Scramb
> ler That was the only voice scrambler I saw used on Marine aircraft in
> Vietnam. I figured the Navy used the same one but maybe the river
> boats were different? Had to change the codes at midnight every night.
> Code books were locked in a safe with two thermite grenades inside. If
> we got overrun, were supposed to set the grenades on top of the safe
> and set them off.
>

That doesn't ring any bells, mentally. I don't know. It was a long time
ago in a land far, far away! I thought I remembered it being about half
as big as the radar head.

I remember that we had TWO forms of encryption. First was the box
itself. Then, when we had to convey specific coordinates (say, for a
strike, but NOT while under fire), we used a paper code-scrambler wheel,
which they changed-out every week.

They weren't taking any chances that Charlie could figure us out from our
radio comms.

Lloyd

Jim Wilkins

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Aug 18, 2016, 10:12:01 AM8/18/16
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"Lloyd E. Sponenburgh" <lloydspinsidemindspring.com> wrote in message
news:XnsA6684675A3B1ll...@216.168.4.170...
Radio Intercept was a very important weapon in the fight against
U-boots, which were required to frequently report their position so
they could be vectored toward Allied shipping.

https://en.wikipedia.org/wiki/High-frequency_direction_finding
Although the position report was strongly encrypted, the direction
they transmitted it from told the anti-sub forces all they needed to
hunt it down. The Germans were well aware they could be located the
same way they tracked down spy transmitters in France, but they didn't
realize the British system could find them instantaneously using a
method they had dismissed as inaccurate. It -was- inaccurate from
distant land bases, but good enough when the HF/DF direction finder
was on a destroyer trailing the sub.

I heard about Spread Spectrum in 1970, though not if we used it in
small tactical radios. It makes a radio transmission indistinguishable
from static.

--jsw


Garrett Fulton

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Aug 18, 2016, 1:22:35 PM8/18/16
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One thing the KY-28 units would do was to make a single "boop" sound in the headsets when you keyed the transmitter. Let you know it was ready to encrypt audio. Never saw the paper wheel units. Yeah, long time ago but it was interesting equipment.

Garrett

Lloyd E. Sponenburgh

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Aug 18, 2016, 2:15:11 PM8/18/16
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Garrett Fulton <lbfu...@windstream.net> fired this volley in
news:cca6c97f-e145-4fe2...@googlegroups.com:

> One thing the KY-28 units would do was to make a single "boop" sound
> in the headsets when you keyed the transmitter. Let you know it was
> ready to encrypt audio.

Yep. That was it!

Lloyd

Garrett Fulton

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Aug 18, 2016, 8:49:37 PM8/18/16
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Well, anyhow, a belated welcome home Sailor. Thank you for your service. :)

Lloyd E. Sponenburgh

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Aug 19, 2016, 6:39:35 AM8/19/16
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Garrett Fulton <lbfu...@windstream.net> fired this volley in
news:3e448f21-8a6d-4457...@googlegroups.com:

> Well, anyhow, a belated welcome home Sailor.

Thank you, sir!
L
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