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Walter Maxwell September 6th 04 11:26 PM

On Mon, 06 Sep 2004 12:57:50 -0700, Wes Stewart wrote:

On Mon, 06 Sep 2004 18:41:37 GMT, Walter Maxwell wrote:

[snip]
|Thanks for the compliment, Reg, that you prefer to take my word for it. However,
|the reason we include the manufacturer is not as a gratuitutous advert, but to
|distinguish between the Cadillacs (Hewlett-Packard and General Radio, among a
|few others) and the non-descripts. The Cadillacs are professional, precision
|instruments, which, when used by knowledgeable people, provide data that can be
|relied upon.
|
|Without knowledge of the quality of the measuring device the reader is
|justifiably suspicious of the data.

Careful Walt. Reg is an Englishman, he doesn't know what at Cadillac
is, other than an American automobile, which makes it suspect.

You should use Jaguar for comparison. Uh oh, better not, that is an
American company (Ford).

Alright, how about Aston Martin. Darn, another Ford.

I've got it; Rolls-Royce! Nope, that's a German car (BMW).

Okay maybe a Bentley. Nooo. That's a Volkswagon.

Surely a Land Rover. Not again! Another Ford.

You're right. HP and GR were the Cadillacs of the industry. [g]


Man, Wes, I sure ran of the road and totalled the Caddie on this one, didn't I?

However, what happened to the Rolls-Royce? Did the Queen boot it out? As I
recall it from my pre-teen days, it was definitely a Brit. And how did it manage
to land in Deutchland? Or did Neville Chamberlin manipulate this one too?

Walt

Richard Harrison September 6th 04 11:49 PM

Walter, W2DU wrote:
"The internal resistance in Class B and C amps has two parts, 1) the
cathode-to-plate resistance, which is dissipative, and 2) the
non-dissipative resistance established by the V/I ratio within the
pi-network tank circuit -- a high resistance at the input and a low
resistance at the output."

It`s true that a parallel resonant circuit constructed of ideal
inductance and capacitance has high (infinite) impedance and no loss.
The configuration of the high impedance in series with the load limits
output. But, we use imperfect components and we seek a limiting
impedance equat to the 50-ohm load, not an infinite impedance.

My take on the non-dissipative impedance is that it comes from the
switched-off time of the Class B and C amps. During this time in each
cycle, no current flows through the amp to cause loss. Likewise, there
is no current from the amp (actually it is a switch operating on and off
at a radio frequency) to the load or tank circuit. The tank circuit
cleans up the pulse mess, filling gaps in the RF cycle.

Best regards, Richard Harrison, KB5WZI



Reg Edwards September 7th 04 12:49 AM


Thanks Stew for your valient attempt to clarify the meaning of Quality in
the electrical measuring instrument field in terms of the motor industry.
Unfortunately the motor industry, as is everything else, is now in the hands
of the International Corporations and is all mixed up.

We are left only with the remains of the confusion with the quality
description "Rolls Royce" which all nationalities understand. It remains
for the same reason that the English language remains. Rolls Royce appeared
at the end of the British era of engineering supremacy which began with the
Bimingham Wire Gauge around the time of the French revolution and continued
through the beautiful Boulton and Watt reciprocating, condensing steam
engines which ruled the Earth for 80 years, as did Britannia's
well-engineered battleships and 16-inch, 18-inch guns.

Our German friends took over at the battle of Jutland and the Bismark
incident. But the optical qualities of Zeiss rangefinders probably had
something to do with it.

But to avoid an international incident, it should be stated the ordinary
engineering educated Englishman quite understands the meaning of "Cadillac"
although he may not have the foggiest idea of where the name came from. Was
it named after a red-indian tribe such as Cincinatti or Detroit?

By the way, I sometimes think that mention or reference to a particular
measuring instrument or the name of a prominent author implies a lack of
self-confidence and conviction in what one is stating.

As for me, I rarely make such mentions if only to avoid the danger of
mis-quoting. The responsibity is then entirely mine.

Although I may jokingly profess ignorance of American electrical measuring
instruments, for several years I was the Government-approved Head of
Laboratory of a measurement standards laboratory of second echelon to the
British National Physical Laboratory. I was familiar with the excellent
qualities of HP, GR, Fluke and similar instruments. I played an original
part in the conversion of the assessment of National worst-case measurement
uncertainties to statistical uncertainty assssment. But I don't brag about
it.
----
Reg, G4FGQ

======================================

Thanks for the compliment, Reg, that you prefer to take my word for it.

However,
|the reason we include the manufacturer is not as a gratuitutous advert,

but to
|distinguish between the Cadillacs (Hewlett-Packard and General Radio,

among a
|few others) and the non-descripts. The Cadillacs are professional,

precision
|instruments, which, when used by knowledgeable people, provide data that

can be
|relied upon.
|
|Without knowledge of the quality of the measuring device the reader is
|justifiably suspicious of the data.

Careful Walt. Reg is an Englishman, he doesn't know what at Cadillac
is, other than an American automobile, which makes it suspect.

You should use Jaguar for comparison. Uh oh, better not, that is an
American company (Ford).

Alright, how about Aston Martin. Darn, another Ford.

I've got it; Rolls-Royce! Nope, that's a German car (BMW).

Okay maybe a Bentley. Nooo. That's a Volkswagon.

Surely a Land Rover. Not again! Another Ford.

You're right. HP and GR were the Cadillacs of the industry. [g]




Richard Clark September 7th 04 01:24 AM

On Mon, 6 Sep 2004 17:49:00 -0500, (Richard
Harrison) wrote:

It`s true that a parallel resonant circuit constructed of ideal
inductance and capacitance has high (infinite) impedance and no loss.


Actually, if it were isolated in museum glass case perhaps, but the
loaded Q, by design, is less than 20, often less than 10, and in the
case illustrated by Mendenhall's FM transmitter = 2. Loss comes to it
by nature as a practical necessity of moving power (transmitting) to
the æther.

The configuration of the high impedance in series with the load limits
output. But, we use imperfect components and we seek a limiting
impedance equat to the 50-ohm load, not an infinite impedance.


The impedance transform of coupling that changed from plate resistance
to load resistance is quite capable of reciprocal transformation (at
least in the rigs of transistor persuasion) to allow return power from
load Z to match towards the source Z. This is the natural progression
of linear design.

My take on the non-dissipative impedance is that it comes from the
switched-off time of the Class B and C amps. During this time in each
cycle, no current flows through the amp to cause loss. Likewise, there
is no current from the amp (actually it is a switch operating on and off
at a radio frequency) to the load or tank circuit. The tank circuit
cleans up the pulse mess, filling gaps in the RF cycle.


By the nature of reciprocity, loss must follow from reflected power
returning through it to a known dissipater, the cathode-plate. If
that cathode-plate is available only intermittently during cycles,
reciprocity is fully functioning through the same available flywheel
of this loaded Tank.

All should notice that if this scenario is NOT working as described,
the caloric demands of reflected power would resolve in a high energy
arc along the way (no one has ever experienced this?). This may
displace WHERE the dissipation occurs, but it does not render
reflected power an inert concept.

All such descriptions can be described in a bulk component model, it
is still the same heat (only the remote arcing becomes an enigma some
would sweep under the rug).

73's
Richard Clark, KB7QHC

Roy Lewallen September 7th 04 01:29 AM

For a story about one of the things that made Cadillac "The Cadillac" of
automobiles, see http://www.uh.edu/engines/epi133.htm.

Caddilac, incidentally, was named after Le Sieur Antoine de la Mothe
Cadillac, the Frenchman who in 1701 built a stockade, trading post, and
settlement called Ville d’Etroit, now known as Detroit. See
http://www.cadillacforums.com/cadillac-history.html.

Roy Lewallen, W7EL

Reg Edwards wrote:

. . .
But to avoid an international incident, it should be stated the ordinary
engineering educated Englishman quite understands the meaning of "Cadillac"
although he may not have the foggiest idea of where the name came from. Was
it named after a red-indian tribe such as Cincinatti or Detroit?
. . .


Richard Harrison September 7th 04 02:16 AM

Wes wrote:
"I`ve got it: Rolls-Royce! Nope, that`s a German car (BMW)."

Who makes the Rolls-Royce jet engines now?

Our company`s first jet airtcraft was a Vickers Viscount prop-jet. We
were in a long cue waiting for one when a wire from Vickers came saying
Cubana Airlines had defaulted on an executive outfitted Viscount for
Fidel Castro. Did anyone in the cue want the aircraft? Our chief pilot
asked the dhairman if he could buy it? The answer was yes. It was
already outfitted almost as we would have done anyway except our
labeling would have been in English instead of Spanish.

I remember landing in Antafagasto Chile right after we got the Viscount.
The Shell Oil tank truck charged out and the operator asked our pilot,
Charlie Walling, which grade of kerosene he wanted, JP-1,2,3,or 4, etc.
Charlie replied he would have to consult the owners manual, a really big
tome. The book said any grade is fine for the Rolls-Royce turbines.
Charlie told the Shell guy to fill it with whatever grade he was long
on. Sure enough, the engines lit right off and ran fine. Most remarkable
was after a flight from Houston, all the engines only required about a
teacup of oil. Our piston engined aircraft would have consumed gallons
of oil on the same flight.

Besty regards, Richard Harrison, KB5WZI


Richard Harrison September 7th 04 03:20 AM

Wes wrote:
"I`ve got it: Rolls-Royce! Nope, that`s a German car (BMW)."

Germans respect British motors. The Messerschmitt Bf 109 resulted from a
competition spurred by a request for proposal to build a new German
fighter aircraft. The Messerschmitt was one of 3 designs from competing
manufacturers who built prototypes for the competition. All 3 featured
British Merlin engines! The production Bf 109 had a 1475 hp Daimler-Benz
engine, but a Merlin powered it to victory in competition.

Hermann Goering declared in Berlin, "If the enemy bombs this place my
name is Mud." Later, as he arrived in a bomb shelter, he said,"Let me
introduce myself. My name is Mud."

A famous German fighter leaded once asked his commander for a squadron
of Spitfires!

Best regards, Richard Harrison, KB5WZI


David Ryeburn September 7th 04 04:24 AM

In article ,
"Reg Edwards" wrote:

But to avoid an international incident, it should be stated the ordinary
engineering educated Englishman quite understands the meaning of "Cadillac"
although he may not have the foggiest idea of where the name came from. Was
it named after a red-indian tribe such as Cincinatti or Detroit?


Debunking mode ON

Cincinnati, Ohio (not Cincinatti) was named not after what we in Canada
call a First Nation but instead after the Society of the Cincinnati, an
organization formed after the American War of Revolution (1776 and all
that). The organization was composed of former American Army officers.
The Society of Cincinnati, in turn, took its name from Lucius (Titus)
Quinctius Cincinnatus, a farmer and former consul who was asked to leave
his fields to become dictator to defend Rome against outsiders, in 458
BC. Under his command Rome's enemies were defeated, and 16 days later he
returned to his farm.

Cadillac, Michigan was named after Antoine Laumet de La Mothe Cadillac,
a Frenchman established a settlement near what is now Detroit, Michigan,
in 1701, and the automobile was named after either the city or the
French settler.

Debunking mode OFF

David
(1) born in Cincinnati, Ohio in 1935
(2) licenced as W8EZE in that city in 1949
(3) learned about Cincinnatus in grade school
(4) wishes that certain US politicians would just return to their
ranches where they could only harm rattlesnakes and cactus plants

--
David Ryeburn

To send e-mail, use "ca" instead of "caz".

Richard Harrison September 7th 04 04:45 AM

Roy Lewallen wrote:
"Cadillac, incidentally, was named after Le Sieur Antoine de la Mothe
Cadillac, the Frenchman who in 1701 built a stockade, trading post and
settlement called Ville d`Etroit now called Detroit."

Something the "Engines of Our Ingenuity" story doesn`t tell us is that
Cadillac was Henry Ford`s company which he sold to what was to become
General Motors

Best regards, Richard Harrison, KB5WZI


Richard Harrison September 7th 04 05:15 AM

Richard Clark wrote:
"This may displace WHERE the dissipation occurs, but it does not render
reflected power an inert concept."

No it doesn`t, but it doesn`t require its acceptance back in the
transmitter either.

I`ll repost my earlier posting as near as I can reconstruct it. It seems
to be lost in cyberspace.

Walter Maxwell, W2DU wrote:
"Consequently, the reflected power reaching the network output is not
absorbed, but instead adds to the power delivered by the generator."

My explanation for the above, which is my observation too, is that an
energy wave experiences a phase reversal between the volts and amps
which it will generate after reflection. That fact makes Bird`s
directional coupler in its wattmeter work.

The transmitter`s output isn`t receptive and won`t absorb a wave that
produces out-of-phase volts and amps, so the reflected wave is
re-reflected from the transmitter, placing its amps and volts back
in-phase.

The newly minted RF and the twice reflected RF are similar, both having
their volts and amps in-phase. So, the similar RF constituents merge to
have a go at the reflection point.

Best regards, Richard Harrison, KB5WZI



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