I am hoping that accuracies of +/- 1 to 2 dB might be achievable.
If you are satisfied with +/- 1 to 2 dB variation, the link I gave to
the Mar MMIC 35dB "calibrated" Noise generator should be
accurate enough.
That why I "forgot" the approximatly statement.

You can not compare noise power with a calibrated sine wave generator.
That's right, not directly.
You can calculate the RMS for a sine wave.
Also calculate the RMS for noise power, but its another formule.
Use the same impedances and frequency's.


If you know the amount of (milli) Ampere's through the noise diode and
know the impedance of the load, you can make power calculations like
we do with DC.
With the calculation method you don't need to have a calibrated noise head.
Someone else discussed the method, let me give the formule.
The formule is in Chris Bowick's book RF Circuit Design.
Its about Shot Noise. (Not thermal)
In^2 = 2qIdcB

In^2 = the mean square noise current
q = the electron charge (1.6 x 10e-19 coulombs)
Idc = the direct current in Ampere's
B = the bandwith in Hertz

Onces you have the mean square current, calculate the power in the load
resistor.
Did not made calculations with it, since I have the opportunity to measure
noise
right away. Will do it in future to check the formule.

The MMIC I used.... I was afraid there would come a question about it.
It's in a factory designed preamp of Japanese origin, has a forgotten
product
number, I mean National, not sure of that.
Searched hours for datasheets, because I was convinced the NF of the device
was less at 144Mhz, the manual stated approximatly 2dB 2Ghz.
EME use 144Mhz, with the knowledge of bipolar transistors that have an
increase of NF with frequency, 144Mhz would have a NF of about 1 - 1.5dB.
The manual said nothing about a lower NF at lower frequency's.
So bought it with the deal, not good money back.
Found the datasheets, the NF was 2.8dB flat from almost DC to 2Ghz.
From there comes the idea of flat NF respons of MMIC's.
I brought the device back to store and got money back. 150$.
More research learnt me that similar devices with less NF in order of 0.7dB
were avaiable for 20$, OK no box around it, no blinky leds.
I know only that the MMIC is obsolete today, forgot the type number.

A single mosfet, BF981 does 1.7dB at 100Mhz and cost about 1$.
I love homebrewing.
With that device you could also calibrate your noise generator.
It matched the input impedance of the 50 Ohm receiver.
Many EME amateurs use it in their preamps.
If they all use the same scheme it would be accurate within a variation
of say +/- 0.1dB ?

Since I can measure noise power, how to calibrate whitout a calibrated
noise head is not a hot item for me anymore.
Just practice.
Before that, I read several books, spent hours on the internet, collected
many
data.
Its only to share thoughts, nothing science, professional or years of
experience,
and yes I can be wrong.
The goal was maybe you can do something with it, for me, maybe there is a
clever
way to determine the NF without calibrated noise head, maybe even whitout
math.

The JT44 software program, I just finished the interface from receiver to
PC.
Details at the original PSK31 homepage.
Used a "Jensen" audio trafo, to prevent ground loops.
A lot to do... no practical data at this moment.

Have read Terry Ritter's stuff.
He said, no white noise at all. Just pink. See the graph's.
Read in some university books, noise is of pink behavior at the lowest
frequency's.
The graph showed the audio band.
White noise is flat (whitin 15 - 20Khz partitions) and at higher
frequency's, and random.
Whit respect to the measurements of course.

There is an increase of NF to higher frequency regions.
How came that MMIC to a flat respons ?