[time-nuts] LF power supply noise
Mike Monett
xde-l2g3 at myamail.com
Sun Jun 21 13:37:31 UTC 2009
>> Again, you might try electronic goldmine's mu metal shielding.
>> Used to be used as a shield around CRTs, etc. Their version is
>> sticky on one side so might make a good trial wrap.
> I has issues with the big permanent magnet of one of my speakers
> made one of my screens going all strange in colours. I had some
> backsides from a pair of racks which I put inbetween, and the
> steel was doing a good job as finding a better path for the
> magnetic fields than through my screen.
> Maybe you should put a few slabs of steel around that HP543310A to
> at least guide most of the magnetic fields back into the core.
>Cheers,
>Magnus
Hi Magnus,
I was having the same problem with funny colors until I switched to
LCD monitors. The problem went away:)
I did try putting a large steel plate between the 543310A and the
2467B. The plate was 12"X12"X1/4" (30.48cm X 30.48cm X 0.635cm), and
I checked it with a magnet to verify it was magnetic, but it had
little effect.
One of the reasons I was attracted to the 543310A was it could
display 14 digits of frequency in one second. Sine then, I have
figured a way to resolve 16 digits in one second, so that part of
the spec is no longer interesting.
The 543310A can do a single-shot time measurement with a resolution
of 200ps, and gets down to 1ps with averaging. The HP5370B does 20ps
single-shot, and will resolve 100fs with averaging. But I have
figured a way to measure 2ps single-shot, and a bit better with
averaging. So that part of the spec is not so interesting any more.
The 543310A will display the phase and frequency changes in a PLL
step response. But you can get the frequency response just by
looking at the VCO DC error voltage. And if you look at the voltage
across the bottom capacitor in a type 3 loop, you get the phase
response. Here's a picture:
-------------------------> to VCO
|
--- C1
---
|
|----------O < - Phase Error
| |
--- C2 \
--- / R1
| \
| |
--- ---
- -
So about the only thing left of interest is histograms of the
jitter. Unfortunately, the 543310A cannot store enough samples to
really make an interesting graph. What I would like to be able to do
is similar to an invention I made for the disk industry long ago,
called Phase Margin Analysis. There is a brief description on my web
page at
http://pstca.com/patents.htm#phasemargin
There is a more detailed description in the paper, "Effect of
Bitshift Distribution on Error Rate in Magnetic Recording", by Eric
Katz and Tom Campbell, at
http://pstca.com/pdfs/katz.pdf
But it doesn't look like the 543310A will be able to do that.
Now that I can beat most of the performance specs of the 543310A, it
doesn't seem worthwhile to spend much time trying to solve the
problem of stray magnetic fields.
So it looks like that problem is not worth pursuing any more. But
this might be a good time to give you a progress report on what I
have been up to these past months.
Some time ago, I mentioned I had a way to measure time difference
with very high resolution. This is similar to what you are trying to
do with DMTD, but I'm confident I can get down to 1e-16 in one
second, and also provide continuous measurements for Allen Deviation
calculations. The technique uses Binary Sampling, and there is a
brief description on my web site at
http://pstca.com/
Since then, I have combined the other developments and came up with
a completely new way of locking a OXCO to the 1pps GPS signals. This
uses Binary Sampling to eliminate the noise due to granularity and
sawtooth error, and should give at least one order of magnitude or
more improvement in performance over anything else that is
available.
The improved performance means you have to start tracking the delays
in the GPS antenna amplifier and the coax to the receiver, and
incorporate them as offsets in the timing. I have figured a way to
measure the changes in electrical length of the coax due to
temperature to better than 1 ps resolution, and can either measure
the temperature of the preamplifier or control it by sending power
up the coax. All this is using one single coax.
Another project in the works is a system to do a three-corner hat
with 1e-16 resolution, with extensions for more channels. I think I
can fit 6 channels in a reasonable size box.
Another project is to measure amplitude and phase noise. The
quadrature method looks most useful, but getting a PLL to give
stable quadrature lock is problematic. Again, Binary Sampling comes
to the rescue, and I am confident I can make a phase noise
measurement equal to or better than anything on the market.
On a side issue, we all suffer from colds and flu infections. These
are usually caused by a virus, and the medical field has nothing
that can treat viral infections and kill the virus.
Just like we need trace amounts selenium and chromium, I believe the
immune system also needs trace amounts of silver to manufacture the
enzymes and proteins necessary to kill viruses. The problem is
unlike sodium, potassium, and calcium, silver compounds are either
poisonous, highly explosive, or completely insoluble. And the silver
must be in ionic form to be usable by the body.
I have been working on ways to generate high concentrations of
silver ions in solution for many years, and have just reached the
final breakthrough in solving the myriad problems. There is a brief
description on my web site at
http://www.pstca.com/silversol/index.htm
The new breakthrough is not described yet, but I am making a new
type of generator that solves all these problems and will start
selling it in eBay soon.
Finally, I have the misfortune to suffer from serious case of
mycotoxosis for many years. This is a devastating problem, and is
completely incapacitating. There is a brief description at
http://www.ibd.ab.ca/files/Mould-chap2.pdf
but it does not describe how serious the problem can be. Just for
example, the toxins on Amanita virosa produces one of the most
potent poisons known to pharmacologists. I read somewhere that a
couple of micrograms of some mold toxins will kill someone in less
than 24 hours, and the toxins are metabolized so they disappear.
This is apparently used by some countries for assassination, since
an autopsy will conclude the death was by natural causes.
Mycotoxosis is incurable, and the only solution is to completely
eliminate any kind of mold spores in the environment. This turns out
to be very difficult to do. The spores grow on most fabrics,
especially cotton, and they cannot be killed with bleach or any
other common household chemical. They require temperatures over 240F
to start having any effect, and it is difficult or impossible to
heat fabrics to these temperatures without melting them or starting
a fire.
Ozone can kill them by removing the outer protective shell, but it
is very difficult to generate high enough ozone concentrations.
Also, ozone generation requires very low humidity, which is
difficult to obtain in the summer when temperatures and humidity are
high. But I have found a very effective solution and am in the
process of making a system to sterilize fabrics. This will be of
great interest to hospitals, clinics, retirement homes, and to
anyone else who may be affected by mold toxins.
One way of reducing the spore concentration in the air is by
filtering. Unfortunately, the spores grow on most filter mediums so
the filter becomes a source of spores. I have developed a new type
of filter that has no organic or synthetic material, so there is no
place for the spores to grow.
These innovations will be of great benefit to others who suffer from
allergies, so I am in the process of developing several new
businesses to bring them to market.
As you can see, I have a lot of very interesting things to do to
keep me busy. I'll be sure to keep you updated on developments in
the time and frequency areas, and if anyone is interested in the
elimination of colds, flu, Shingles, dental cavities, peptic ulcers,
and the removal of moles and warts, you can contact me separately
via the address on my Silversol web site.
Thanks,
Mike
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