[time-nuts] LF power supply noise

[Mike Monett]

  >> 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