In recent correspondence we have been regaled with the possibilities,
the probabilities, the certainties that some fastidious, and
well-heeled Ham "could" achieve the determination of RF power to
within 0.1dB of its actual value.

This gives me considerable pause as to how that actual value was
determined itself, but the explanation of that drifted into the fog of
vague generalization and the dismiss of standards. I characterized
this as delusional at worst, and simply fantasy short of being
fantastically rich.

So, given the swings of claims that seem to hinge on access to exotic
equipment, I was offered:

On Sat, 3 Jan 2009 , wrote:
A ham seriously interested in 0.1 dB measurements will probably be
able to scrounge up something to use as a transfer standard
....
The how to do it is all out there. What was "state of the art" for a
national laboratory in 1970 is fairly straightforward garage work
these days, and, a heck of a lot easier because you've got inexpensive
automation for making the measurements and inexpensive computer power
for doing the calibration calculations and uncertainty analysis.

None of these suggestions attended any actual real application beyond
the thread's discussion of measuring power from an antenna in a high
power RF field from a nearby (10s of wavelengths distant, perhaps)
transmitter.

The quote above fairly encompass the solution in Jim's own words.
There were certainly more words, and they can be appended to this
thread or those above amended as Jim sees fit to force the outcome to
match the claim. However, I would like to see something a little more
real than fanciful.

This would include a real METHOD and BUDGET for the claim:
On Tue, 23 Dec 2008 10:29:05 -0800, Jim Lux
wrote:
At HF and VHF, you should be able to do power measurements to a tenth of
a dB, with moderate care.

1. That budget (with an ironic eye towards the language's claim of
"moderate") is a generous $1000 - with that budget being invested
solely towards the measurement (and not in the capital equipment of
transmitter and antenna) through the costs of ancillary equipment
acquisition and of guarantees of absolute accuracy as further
described below.

2. That frequency is 14.1MHz.

3. That power is 10mW.

4. That application is measuring the full power applied from a 100W
rated Ham grade transmitter/transceiver directly (or through a
directional coupler) to
a. an unloaded quarterwave thin antenna sited over 120 half-wave
radials placed slightly above, upon, or slightly below the ground
(slightly being defined as that recommended by an NEC modeling tool
for ground radial modeling); or
b. an unloaded halfwave thin antenna sited in free space.

5. That fully expressed tolerances for all components, capital and
ancillary equipment involved where the budget also absorbs their cost
of determination of their contribution to error.

6. That fully expressed tolerances for sources of system error.

7. That outcome of accuracy of power determination being applied to
the nominal 100W of power at the load and not the nominal 10mW of
power to the sensor.

* * * * * * * *

This will be a very short thread devoid of conclusion when the
poster(s) suddenly become aware of the expense exceeding the budget.
For those who challenge this artificial budgetary limitation, try
asking Congress for a bailout.

73's
Richard Clark, KB7QHC

Measuring power to 0.1 dB? Jim, this is still January, April 1 is four months
away. Aren't you a little early for April Fool's Day?

Walt, W2DU

On Jan 4, 2:12*pm, "Walter Maxwell" wrote:
Measuring power to 0.1 dB? *Jim, this is still January, April 1 is four months
away. Aren't you a little early for April Fool's Day?

Walt, W2DU

Wow
Walter Maxwell has joined Richard Clark in an effort to label Jim in
front of everybody
as a fool. Thats right, these two bozoes have decided to gang up on
Jim trying to discrace him
because there is a difference of opinion. Jim was drawn into the
subject because he was not aware
of Richard's background and Walt joined in in an effort to cover up
Richards critisicm of his new aproach to make money i.e. his book
called reflections which is just a bunch of BS with respect what
happen s at the end of a fractional wave antenna.
He will get some money from unsuspecting hams to this group and maybe
roars of joy from some in the nasty stabbing of the poster named Jim.
Walter and Richard deserve each other in this personal attack on a
poster. Both of you need to join the kb9....poster who is intent
of disrupting this group by injecting rudeness and injury to its
members.
Art Unwin KB9MZ....xg (uk)

Richard, Art says we're bozos. Did you know that? I didn't. When did this come
about? I don't believe I was born that way. Yeah, and when was it we decided to
gang up on Jim? And what kind of a stabbing device did we plan to use on him? I
can't remember.

And please, Art, did you have to put us in the same class as that kb9? I don't
think Jim is the fool here.

Walt, W2DU

On Jan 4, 2:55*pm, "Walter Maxwell" wrote:
Richard, Art says we're bozos. Did you know that? I didn't. When did this come
about? I don't believe I was born that way. Yeah, and when was it we decided to
gang up on Jim? And what kind of a stabbing device did we plan to use on him? I
can't remember.

And please, Art, did you have to put us in the same class as that kb9? I don't
think Jim is the fool here.

Walt, W2DU

Walter both you and Richard take a delight in hurting people as your
histories shows.
I suppose you can call anybody who opposes you in a discussion
personal insults,
names or anything else to achieve your aim to harm those who do not
provide an
alliance with you and what you say. Both of you have done it many
times before
and will probably do it again to unsuspecting posters. I just want to
ensure that
newcomers recognise both of you for what manner of men ( should I use
that term?)
you actually are. Forewarned means fore armed and that goes for your
crappy book also
that you hawk for money with hams on the pretence you are supplying
scientific hams
and not the unsuspoecting :"
ordinary "hams.
And YES I put you in the same class as KB9......
since your intention of destruction to this newsgroup is the same as
his
as you have just shown by this ugly attack with intent to hurt.
You and Richard deserve his companionship as you are like people in
what you do
Art Unwin KB9MZ

Art wrote:
"And YES I put you in the same class as KB9...."

Art is overheated.

0.1 dB could be a power gain of 1.02 or 0.977.

If the power were 100, and the power read 102 or 98 that would be about
0.1 dB (from Terman`s Handbook).

My Bird Model 43 has a specified accuracy of +5% or -5% of the
full-scale meter reading. It is a reasonably accurate meter for field
use. If the scale was 100 and it should be reading 50, it could read 55
or 45 and be within specification.

My usual hope when making commercial measurements was within 1.0 dB.

Best regards, Richard Harrison, KB5WZI

Art Unwin wrote:
On Jan 4, 2:12 pm, "Walter Maxwell" wrote:
Measuring power to 0.1 dB? Jim, this is still January, April 1 is four months
away. Aren't you a little early for April Fool's Day?

Walt, W2DU

Wow
Walter Maxwell has joined Richard Clark in an effort to label Jim in
front of everybody
as a fool. Thats right, these two bozoes have decided to gang up on
Jim trying to discrace him
because there is a difference of opinion. Jim was drawn into the
subject because he was not aware
of Richard's background and Walt joined in in an effort to cover up
Richards critisicm of his new aproach to make money i.e. his book
called reflections which is just a bunch of BS with respect what
happen s at the end of a fractional wave antenna.
He will get some money from unsuspecting hams to this group and maybe
roars of joy from some in the nasty stabbing of the poster named Jim.
Walter and Richard deserve each other in this personal attack on a
poster. Both of you need to join the kb9....poster who is intent
of disrupting this group by injecting rudeness and injury to its
members.
Art Unwin KB9MZ....xg (uk)

Calm down, Art, it's a disagreement, not an assassination. If you'll
just wait a day or two, you'll most likely learn something.
73,
Tom Donaly, KA6RUH

On Jan 4, 5:36*pm, "Tom Donaly" wrote:
Art Unwin wrote:
On Jan 4, 2:12 pm, "Walter Maxwell" wrote:
Measuring power to 0.1 dB? *Jim, this is still January, April 1 is four months
away. Aren't you a little early for April Fool's Day?

Walt, W2DU

Wow
Walter Maxwell has joined Richard Clark in an effort to label *Jim in
front of everybody
as a fool. Thats right, these two bozoes have decided to gang up on
Jim trying to discrace him
because there is a difference of opinion. Jim was drawn into the
subject because he was not aware
of Richard's background and Walt joined in in an effort to cover up
Richards critisicm of his new aproach to make money i.e. his book
called reflections which is just a bunch of BS with respect what
happen s at the end of a fractional wave antenna.
He will get some money from unsuspecting hams *to this group and maybe
roars of joy from some in the nasty stabbing of the poster named Jim.
Walter and Richard deserve each other in this personal attack on a
poster. Both of you need to join the kb9....poster who is intent
of disrupting this group by injecting rudeness and injury to its
members.
Art Unwin KB9MZ....xg (uk)

Calm down, Art, it's a disagreement, not an assassination. If you'll
just wait a day or two, you'll most likely learn something.
73,
Tom Donaly, KA6RUH

You are probably correct but he called him a fool not that he was
mistaken
\so he meant to hurt. I am not willing to stand by for a day and do
nothing
for his defence. I have my faults I suppose
Best regards
Art

Art, I may be a bozo in your mind, but apparently you lack a sense of humor. My
jibe at Jim was in fun, and I'm sure he took it that way. I'm also sure he
wasn't in any way hurt by my humor, which in your own mind seems to think he
was.

Walt

Art wrote:
"-----i.e. his book called "Reflections" which is just a bunch of BS
with respect to what happens at the end of a fractional wave antenna."

Everyone should have access to the 3rd. edition of "Antennas" by Kraus,
Marthelka, and associates. It is a true treasure. On page 177 is found
Figure 6-7, Approximate natural-current distribution for thin, linear,
center-fed antennas of various lengths.`

In each case, at the open-circuit end current drops to near zero. No
surprise, as Terman says on page 866 of his 1955 opus:
"Under most circumstances the losses are sufficiently low and the ratio
of wire length to diameter sufficiently great so that to a first
approximation the current distribution can be taken as that for a line
with zero losses; it then has the characteristics discussed in Sec.
4-5."

Section 4-5 is titled: "The Effect of Attenuation on Voltage and Current
Distribution".

Point is that antennas share current distribution characteristics with
transmission lines, and Sec. 4-5 is in Terman`s Chapter 4 (Transmission
Lines). This chapter starts on page 82 of "Electronic And Radio
Engineering" from that wonderful year 1955. The transmission line
chapter shows in excellent detail how incident and reflected waves
combine, and the energy patterns produced on antennas as well as on
lines.

Walter Maxwell is in-step with Terman and Kraus.

Best regards, Richard Harrison, KB5WZI