From: John Smith on Jul 29, 6:08 pm

Len:

10mhz?
My gawd man, I can walk that fast!

Heh heh heh...we'll just put you down on a bench with a good
scope, warm up the soldering iron, hand you a bunch of DIPs
and see if all your gate delays will allow you to get all of
the sequence states in order... :-)

Reset the time to about 1976 with conventional TTL DIPs, well
before the "HC" CMOS zilch-gate-delay technology was developed.
It was also well before the GIGAHertz-clock PCs appeared. At
best the PC clocks were struggling to keep up at 10 MHz (at
least the affordable ones) and microprocessors running at that
clock rate were "inconceivable."

I stand behind what I said, no perfect random number generators exist, if you
need a really good one--it can't be done with computer algorithms (but, the one
doing our lottery is a really **** poor one--probably worse than your "no
repeats for 913 year one @ 10mhz" even... grin

John, that's why they call it a PSEUDO-random sequence generator.
PSEUDO, "close enough" but not exact.

I gave up playing any Lotto years ago. I won all of $55 and
spent at least three times that in order to "win" that. It
was a cheap thrill while it lasted. :-)

Just because YOU didn't win anything is not a reason to be
accusatory. :-)

It most EXACTLY becomes a question of, "How good of a random number generator
do you need?"

Depends on the application. If you want to scramble (encrypt)
voice/data/video/whatever, you want one to SYNCHRONIZE the
unscrambler (decrypt) to enable restoration to the original.
That's where the PSEUDO-random thing comes in.

PRSGs are invaluable in certain kinds of measurements that
require "noise" added...and then that "noise" subtracted in
order to "see" whatever non-random stuff is there. One of
those is building stability (especially for robustness
during earthquakes). H-P Test and Measurement Div (Agilent)
had a good series of AppNotes on that with a high-power
shaker (low-power compared to quakes) "modulated" with a
PRSG and the sync off of the PRSG used to subtract the
deliberate shaking from vibration sensors in order to gain
the resonant modes of the building. Another series of App
Notes described a similar method to extract resonances in
electronic circuits, even do a pseuod-reconstruct of frequency
response. That was three decades ago.

If you get into any metrology at all, you WILL find that this
"artificial noise" is an accepted practice in many physical
analyses from mechanics of structures to electronics. It just
CANNOT be done any other way except by PSUEDO-random
techniques.

I grant you, most apps do not need that good of one, games of chance in
reno/las vegas are ran off damn poor ones...

Tsk. Sounds like you've been to Vegas and haven't won much?

:-)

No problem to me. Wife and I will be in Vegas along about
the beginning of October and try a few of those games...
along with the other R&R available.

We use electronic banking methods a lot now for personal
finances. Quick, easy, and COMFORTABLY SECURE coding that
we can depend on. Nobody has hacked our bank accounts
yet. The worst we can expect is some doofus courier
"losing" a back-up tape during physical transport.

Also, if you read about egg at princeton.edu, you will see that computer random
number generators are really a bad idea, the human mind can influence
results... on some quantum-metaphysical level it seems the mind has powers
which we have only guessed about in fairy tales... I leave that to your
further research however...

Yah, yah, yah. You are beginning to sound like a "small medium
at large," John. Or, you read the same series of science-
fiction stories in old ANALOG magazines as I did! :-)

"Egg?" Edgerton, Germehausen, and Grier, the company?
"The Cuckoo's Egg" by an astronomer-turned-hacker-catcher?
[that's a BOOK if anyone else is looking in and wondering
what the fork we are talking about...]

In THIS newsgrope we've got "state-of-the-art" radio amateurs
who insist and insist and insist that morse code comms are
WAY, WAY faster than any (hack, ptui) TTY and MUCH, MUCH
better (and "easier") than sending text messages over a cell
phone! Just ask them and they will issue Pronouncements to
that effect! [and they HAVE] Their spiritual metaphysics
will defeat ordinary physical laws three ways from Sunday!

Remember Len, we really do agree on most though... or, close enough...

Not really...but, carry on, auld chap... :-)


bit bat