> -----Original Message-----
> Some of Shannon's better known known theorems include
> the Sampling Theorem, which indicates that a bandwidth-limited
> signal can be reconstructed only if sampled at least at twice
> the frequency of the highest-frequency spectral content.
>
Take a 1 Vpp@40Hz Sinewave, highest-frequency spectral content is 40Hz,
sample it at twice this frequency, 80Hz, sample at 0 and 180 degrees (0Vpp
Amplitude), the reconstructed sinewave will be 0Vpp at 0 Hz. Oh well, guess
Shannon's theorem is incorrect...
steve
Owen,
I've got the original IBM system install disks and RPG subsystem on 8"
floppies. Unfortunately, that's the only software I have for the /36.
Wouldn't mind finding COBOL or some other more interesting software for it.
If you don't have RPG already installed, I'll loan you the disks (I guess
it's safe to loan software to a fellow Robertson).
Send your address and I'll try to get it out next week.
Steve Robertson
>
>Sure. I'll have to check to see if it's on there already or not, but if it
>isn't, I'm interested. Is it on 8" diskettes?
>
>Thanks,
>Owen
>
>on 2/27/01 2:36 PM, Steve Robertson at steven_j_robertson(a)hotmail.com
>wrote:
>
> > I've got RPG for the /36. Don't know if that interests you or not?
>
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com
VAX g00r00s!
This question was posed to me:
Did VMS have a built in utility that allowed to 1) time how long a given
user was logged in, and/or 2) track what directories on the VAX the user
entered?
Answers appreciated. Thanks!
Sellam Ismail Vintage Computer Festival
------------------------------------------------------------------------------
International Man of Intrigue and Danger http://www.vintage.org
Hi,
Can someone provide me with the contents overview of the following book
if you have it:
Transputer Applications Notebook - Systems & Performance
It is basically a collection of technical notes from INMOS. I need to
know if there are any technical notes that are in this book that are NOT
in the following two books:
Inmos Technical Notes
Inmos Communicating Sequential Processes
Thanks,
Ram
Anyone using or hacking a Wang VS-100 system for anything these days? I
ran across a very complete looking one in a storage building but as it's
reasonably huge I've left it for the time being. O/S is unique to Wang
is it not? Too proprietary to be of any use?
Thanks, Craig
My thoughts and prayers go to all of us on the List who have been
affected in any way by the recent siesmicity in Seattle. I hope sincerely
that your families, yourselves, and your Stuff is okay.
Here in India, as you might know, there was a huge quake which levelled
a whole region, though I live 1250 miles from it, it was felt here (In
Madras)
Also, there has been El Salvador, and recently in the Afghanistan
region, some activity which affected lives.
I hope to hear good nes from some of the regular members who post from
the Pacific Northwest.
Cheers
John
Does anyone know where I can find an Apollo
workstation? I am looking for the vintage that
runs the Domain OS. I would also prefer a
source somewhere in Europe, although I could
make special arrangements for the US if
necessary.
Bill
Amsterdam, NL
On Dec 19, 23:18, Sellam Ismail wrote:
> On Tue, 19 Dec 2000, John Foust wrote:
>
> > Some .ram files merely reference an .rm file via http://,
> > such as a .ram that contains:
> >
> > http://streams2.vortex.com/rmf/daisy.rm
> >
> > which would allow you to just enter that URL directly,
> > or save-as, and then you'd have the .rm file.
>
> Sheer genius. But it didn't work :(
I used the audio hardware on one of my SGI machines to snarf the stream as
it played and uploaded it to
http://www.dunnington.u-net.com/temp/daisy.wav for you (about 3MB).
I was intrigued by the recording, and I knew I'd seen a reference somewhere
else, so I spent a while hunting for more information. Interestingly, the
first reference I found was in the classiccmp archives, from two years ago!
But the following may be of interest:
http://www.spectrum.ieee.org/INST/mar98/histquiz.html
(a little background)
http://neil.franklin.ch/Usenet/alt.folklore.computers/20001109_Musical_main…
(several recent informative Usenet posts)
http://korova.com/kmr98/kmr8002.htm
(near the bottom, explains that "Daisy" was useful because it contains
all the notes in an octave)
http://www.mindspring.com/~dmaxey/ssshp/ss_btl1.htm
(relevant published papers and archive tapes at BTL, including the one
from which "Daisy" is taken)
--
Pete Peter Turnbull
Network Manager
Dept. of Computer Science
University of York
For those who may not have caught a news report lately, our area was hit
with a pretty good-sized shaker today -- 6.8 on the Richter, to be exact,
with the epicenter about 30 miles southwest of Seattle.
The vast majority of the damage was in the older sections of the state
capitol in Olympia, and in parts of downtown Seattle. The local news had
some footage of a twisted pile of metal, buried under (literally) a ton of
bricks from an older building. Said pile had once been an SUV in the Ford
Bronco (full-size) class.
The building I work in at Boeing's Renton plant appears to have sustained
minimal damage, though it is still closed at this hour. It is expected to
reopen tomorrow unless major structural problems are found.
Thanks be to God, the sum total of our "damage" here at home was a stuffed
animal fallen from its shelf, and my mate's closet door jarred out of
alignment with its track guide.
I have yet to check on the level of damage at the local used-computer
places. The only fatality I know of, and I'm not even certain it can be
directly attributed to the quake, is that a heart-attack victim died.
And that's the Way it Is from southeast of Seattle, Kent's East Hill. At
least Peter Jennings wasn't on the air to say "Earthquack" like he did with
the Bay Area's 'Quake of '89.' ;-)
Keep the peace(es).
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Bruce Lane, Owner and head honcho, Blue Feather Technologies
http://www.bluefeathertech.com // E-mail: kyrrin(a)bluefeathertech.com
Amateur Radio: WD6EOS since Dec. '77 (Extra class as of June-2K)
"I'll get a life when someone demonstrates to me that it would be
superior to what I have now..." (Gym Z. Quirk, aka Taki Kogoma).
Hi,
This message replies to several in the thread about NeXT MO disks.
On Mon, 26 Feb 2001 Jerome Fine wrote:
>> A question about MO disks and the Canon MO drive installed in some NeXT
>> cube computers.
>> I know NeXT MO disks are single-sided, commonly quoted as having a capacity
>> of 256MB.
>
> I have some rather old MO disks as well, but they are made by Sony and are
> for a 5 1/4" Magneto Optical Disk drive - an S501. They are very close to
> 290 MBytes on each side and are formatted for 512 bytes per sector.
The sector layout is stamped into the disk at the factory; it is not possible
to change. That's why there are two variants, e.g. 600MB and 650MB for first-
generation drives. 600MB disks have 512-byte sectors, and 650MB disks have
1024-byte sectors. The extra capacity of 650MB disks is because less space is
wasted on sector headers. Without special driver software, some computers only
work with media with 512-byte sectors, which is why the lower-capacity disks
exist.
(On a kind-of-related note: I understand the sector layout or servo tracks of
e.g. Zip disks are written at the factory. Does that mean if you degauss a
Zip disk it is then useless, and cannot be reformatted?)
> I don't know anything about the NeXT hardware, but if the shoe fits, ....
>
>> ...
>
> Since 250 MBytes per side is close, they might be the same as the ones I
> have. Mine are 5 1/4" disks and formatted at 512 bytes per sector and hold
> about 295 MBytes on each side for a total of about 590 Mbytes per disk.
The Canon/NeXT disks are not the same as the ISO standard 600/650MB disks
which the Sony drive uses. They may be the same physical shape, but that is
all.
A page on the Sony web site indicates that NeXT drives can use 600/650MB
disks. I'm almost certain that is wrong. (The URL of the page is
http://www.sel.sony.com/SEL/rmeg/data/cg/table1mo.html - scroll down to the
Canon section.)
> In addition, a friend of mine has a large number of these disks which he no
> longer wants. For a nominal charge plus shipping and handling, I am sure
> that they can be made available. The shipping alone (these weigh about 1/2
> lb. EACH) will likely be more than the disks, so I do think it is a good
> deal. On eBay, they often try to get the suckers to pay over $ US 5.00 a
> disk just to start, although sometimes they start at a more reasonable $ US
> 2.00 each. I am in Toronto, so the shipping may be more than you want to
> pay!
Shipping may not be that expensive. A while ago I bought 50 5.25" MO disks,
and shipping within the USA by UPS cost $17 (from memory). The "media mail"
USPS rate is comparable to book rate, but for computer media.
Getting an older MO drive and disks is a really cheap way to get reliable
removable storage. The drives are so cheap (usually under $25 for a 650MB
drive, under $50 for 1.3GB) it is practical to get one for each computer.
Used disks cost $1 or $2 each. Way better than using a Zip drive, I think.
On Mon, 26 Feb 2001 Jeff Hellige wrote:
>> I have some rather old MO disks as well, but they are made by Sony and are
>> for a 5 1/4" Magneto Optical Disk drive - an S501. They are very close to
>> 290 MBytes on each side and are formatted for 512 bytes per sector.
>
> If I recall correctly, one of the problems with the MO drives
> was that there was little to no standardization of the formats or
> disks for the drives.
That's not really true any more. Well, since 1991 anyway.
Before the original ISO standard was finalised, there were some problems with
interchanging disks between drives from different companies. This was
around 1989-1990. I believe most manufacturers updated the firmware of their
drives to solve the problems.
The major standard 5.25" MO capacities are:
600/650MB "1x", ISO 10089 Format A
1.2/1.3GB "2x", ISO 13549
2.3/2.6GB "4x", ISO 14517
4.1/4.8/5.2GB "8x", ISO 15286
8.6/9.1GB "14x", new, no standard published yet
Newer drives can usually read all, and write to some or all previous
standards.
Currently 5.25" MO drives are manufactured by Maxoptix and Sony (HP and IBM
drives are manufactured by Sony). They are completely compatible; a Maxoptix
drive can read disks written in a Sony drive etc.
In the past, drives have also been made by at least Ricoh, MOST, NEC, Nikon,
Sharp, Pinnacle Micro, IBM, HP. Disks written on any of those should be
readable on modern drives.
There are some other less common capacities; Hitachi made a drive which used
1.7GB/2GB disks, Pinnacle Micro's Apex drive could use 4.2/4.6GB disks, and
Maxoptix made drives which could use 900MB/1GB disks. All those types of disk
are still available new incidentally, and current Maxoptix drives can read
and write the 900MB/1GB disks.
There are a few uncommon types which you will rarely come across:
- Pioneer make MO drives which are mainly used in medical imaging
applications; apparently some CT scanners use Pioneer drives. Drive and
media prices for these are quite high, as Pioneer are the only source.
There are three types of rewritable MO media for Pioneer drives: 654MB (ISO
10089 Format B), 1.7GB and 2.2GB.
- ... and of course the Canon 500MB disks.
On Tue, 27 Feb 2001 Jeff Hellige wrote:
>> Pinnacle called their drive the REO-650 and in a dual configuration it
>> was called an REO-1300. Since I also have an REO-650 and have
>> looked inside, I can verify that on the early models, this was the actual
>> hardware. Obviously, both the S501 and the REO-650 use the
>> identical media.
>
> I took a look at the Pinnacle drive today and it is a
> Pinnacle Micro Sierra Optical Hard Drive with a 1.3gig capacity on
> 5-1/4" removable media. Supposedly it is a double-sided cartridge
> capable of holding 650Mb per side. It appears to be a standard SCSI
> drive, but unfortunately I do not have any of the disks for it.
The Sierra is a very nice drive, at least going from the specs; I haven't used
one. Perhaps the fastest 1.3GB MO drive: spins at 4500rpm, average seek time
19ms, 4MB cache memory.
You can use any 1x (600MB, 650MB) or 2x (1.2GB, 1.3GB) MO disks with it. These
can often be found on eBay for a couple of dollars each. 1.2 or 1.3GB disks
will give faster data transfer than 600 or 650MB ones.
-- Mark
