LARTed with a tesla coil, right? So how do you propose using a pc in
a building without three-prong sockets?
>I do, and if I catch anyone removing safety earth connections in my
>workshop, they will be LARTed. I am serious. I've worked enough with
the
>mains to know how dangerous it can be.
>
I doubt 240 vs. 110 is much difference as far as heart muscle is
concerned
>(a) If I want to commit suicide I will do :-). But I don't want to set
>booby traps in my workshop. Perhaps I'm more careful becausewe've got
240V
>mains here.
>
So, why have I never felt anything touching a PC case? I've done it
many times, I've touched insides many times, and I've never felt so
much as a tingle. Would I be able to use a VOM to find this voltage?
>
>Right, an explanation. The 'Earth' wire goes to the metal PC case, and
>also to the thrid pin of the plug. 'Neutral' is connected to earth at
the
>main distribution board (US), last distribution transformer (UK), and
is
>effectively earth. And live is 110V (or 240V) above that.
>
>Now, the 2 capacitors on the left form a capacitive potential divider.
So
>if the earth wire is not bonded to ground, then the midpoint of that is
>going to be at half mains voltage - 55V (or 120V) wrt neutral, which is
>efectively local earth. That means the case of the PC - the external
metal
>case - is at that voltage wrt local earth. Now the capacitor values
>_should_ limit the available current, but I'd not bet on it. Also, the
>capacitors should be a special safety type which are unable to fail
>shorted (I forget the type - it's either class X or class Y), but I've
>seen plenty of cheap-n-nasty PSUs with just 600V capacitors in this
>position. If I spot them like that, they get replaced, BTW.
>
>And that's what I'm going on about. Not that the keyboard was live, but
>that the metal case of the PC had a significant voltage wrt local
earth.
>Normally you'd not notice it - the front panel is probably plastic, so
>are the floppy drives, etc. But reach round the back to plug in the
>keyboard cable, touch the back of the case, and zap!
>
>
>> like mine, it's very difficult to maintain wiring and even talk about
>
>> sometime...I'm very lax with safety precautions. There is no way the
>
>I am not fanatical about safety - I do plenty of things that can be
>considered dangerous. I use machine tools, I change CRTs, I work on
>30kV supplies, I work on mains, I repair SMPSUs, I even work on live
>equipment if necessary. And yes I defeat safety interlocks if there's a
>good reason for so doing, and I know what the consequences are. But
there's
>no way you'll catch me removing an earth connection without a _very_
good
>reason.
>
>
>> boy could have electrocuted himself with any modern keyboard I know
>> of, since it's mostly impossible to get to the components inside them
>> w/o taking the thing apart. An XT keyboard, OTOH, is metal which
>
>The backplate of an XT keyboard is connected to the body of the DIN
plug.
>If that's live for any reason, then there's something seriously wrong -
>see above.
>
>> could kill someone if the keyboard is damaged or plugged into the
>
>There is no voltage on a keyboard connector that can kill - at least
not
>if the rest of the PC is correctly wired. I'd touch any component in a
>working XT keyboard and I'd live to tell the tale.
>
>> wrong place. More likely is that he touched a bad power cable with
>> hand. If the PC got moved and the keyboard got unplugged, it could
>> undo any cables spliced together w/scotch tape (another of my bad
>
>Argh!!! I prefer to use proper cable joined with proper connectors -
with
>insulation and strain reliefs.
>
>-tony
>
>
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
In message "VC404 The Standard", lwalker(a)mail.interlog.com writes:
> One of my recent curbside finds is a machine put out by a Canadian company
>based in Waterloo Ont called Volker-Craig model vg-400. On the front it has a
>title VC404 The Standard.
I also have a 404, discarded from a university lab many years ago.
These terminals seem to have been popular in university student
terminal rooms because they were relatively cheap. I seem to recall
that the company founders were ex-University of Waterloo people.
I've seen 404s not just in Canada but also in Britain, where they were
the standard terminals on a university Vax system I once used. So I'm
not too surprised Tony has a tech manual. (Actually, I wouldn't be
surprised if Tony had a tech manual for Noah's Ark :)
>It has a k-b attached with ribbon cable
Unfortunately the keyboards were not that robust and after a few
generations of students pounding away on them, the keyboard or the
ribbon cable often became unreliable.
>In the back it
>has a 25 pin RS232 connector, a BNC labelled "composite video" ,2 switches :
>one 3-pos.to configure parity the other "Transparent on off"
That video connector on the back was useful for hooking into a big
classroom overhead monitor so a whole class could learn from observing a
terminal session.
These terminals are very helpful for debugging RS-232 communications.
The "transparent" switch on the back lets you choose to display all the
ASCII control codes (eg, instead of performing a "line feed" it displays
a little LF symbol).
Larry, I don't have any tech docs but I do have a thin user manual.
About all it tells you is what the special control codes are to clear
the screen, move the cursor, etc. Still, it's the information you need
to run Wordstar with it! E-mail me with your snail-mail address
and I'll run off a copy for you.
Regards,
Arlen
--
Arlen Michaels
Nortel
Ottawa, Canada (613) 763-2568 amichael(a)nortel.ca
I have never gotten real spam to my address, non-real spam being
unwanted jokes and chain letters from people who have my address.
It's amazing, every few weeks the "Bill Gates goes to heaven" joke
is rediscovered...
>I don't know, fact is that my SPAM statistc shows an increase
>of around 5% since I'm on this list - this might be just the
>usual SPAM inflation, but taking your guesses, it might also
>be list related. (My SPAM statistics are don by my self made
>SPAM killer bot - a vcollection of key word filters - the most
>usefull filter just triggering '$$$' :)
>
>Gruss
>H.
>
>--
>Ich denke, also bin ich, also gut
>HRK
>
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
Weird. Maybe there is damage to some ROM somewhere? If you have
another floppy drive, try plugging that in. I've never had any
problems with my Superdrive
>On Tue, 21 Jul 1998 19:45:51 -0700 (PDT), Tom Owad
<tomowad(a)earthlink.net>
>wrote:
>
>> 3. It will not accept an 800k disk formatted by an SE/30 which
>>contains System 6.0.1.
>> 4. It *will* accept an 800k installer disk, but it complains
that
>the
>>disk contains a "minimal" script file, and that I need a "full"
install
>>script. Arrrgh...
>
>>>So you actually get a happy Mac when you insert that disk? Have you
>>>tried a genuine System Tools disk?
>
> Yes, this is an *original* 6.0.1 installer disk from the
aforementioned
>SE/30. It boots, but complains about the script type. This is the
*only*
>disk that I've gotten to work so far.
>
>
>Rich Cini/WUGNET <nospam_rcini(a)msn.com>
> - ClubWin/CW6
> - MCP Windows 95/Windows Networking
> - Preserver of "classic" computers
><<<< ========== reply separator ========== >>>>>
>
>
>
>
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
I am sorry, but I really have to ask this before I do anything else.
THe keyboard ribbon cable on the thing had some chipped contacts at
the location of a bend near the socket. This prevented use of many
keys. So, I trimmed the cable. This lets the kb work fine, but is
barely long enough to get to the edge connector, and once there it
won't stay properly. And now the damn thing is becoming chipped
again. What should I do? I can't replace the ribbon because the whole
keyboard circuit board is one piece of plastic film (two layers).
______________________________________________________
Get Your Private, Free Email at http://www.hotmail.com
At 02:41 PM 7/22/98 -0700, you wrote:
>>I'm also planning obfuscation of e-mail addresses, to foil spammers. My
[...]
>That hardly seems worth it. Do that robots really browse web pages for
>email addresses (particularly pages like this)? And what if my email
Yep, they do. I've got a page stored on my pager that came from a spammer
trolling for e-mail addresses on web pages. (My pager can be reached at
<4152010273(a)alphapage.airtouch.com> and there is are links to said address
on my site.) I've gotten several such pages (but only keep the one to show
people.)
--------------------------------------------------------------------- O-
Uncle Roger "There is pleasure pure in being mad
roger(a)sinasohn.com that none but madmen know."
Roger Louis Sinasohn & Associates
San Francisco, California http://www.sinasohn.com/
I was corresponding with this fellow a while back. He indicated that some
or all of the gear listed -might- get shipped to a staging point in the US
of A.
I've had no further word on that, and I'm in no position to buy anything
right at the moment. However, that may not hold true for other
CLASSICCMP'ers. With that in mind, check out the site and, if interested,
contact Mr. Tey directly.
Attachment follows.
-=-=- <snip> -=-=-
>X-Sender: wmtey(a)post1.com
>X-Mailer: QUALCOMM Windows Eudora Light Version 3.0.5 (32)
>Date: Thu, 23 Jul 1998 17:41:11 +0800
>To: "Anuar Omar" <omara(a)tm.net.my>, joe(a)ar.co.th, sakchai(a)ar.co.th,
> Bruce Lane <kyrrin(a)jps.net>, chaiyut(a)irc.co.th,
<big snip of CC's>
>From: william tey <wmtey(a)post1.com>
>Subject: bargain hunting!
>
>pls visit our web page at:
>
>http://www.berkeley.com.sg/surplus.htm
>
>for best bargain in town!
>
>
>william tey
>berkeley electronics pte ltd
>135 joo seng road #05-03
>pm industrial building
>singapore 368363
>joo chiat p.o. box 0859
>singapore 914202
>tel: (65)382-5998, fax: (65)382-5982
>email: wmtey(a)post1.com
>
>
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Bruce Lane, Sysop, The Dragon's Cave BBS (Fidonet 1:343/272)
(Hamateur: WD6EOS) (E-mail: kyrrin(a)jps.net)
"Our science can only describe an object, event, or living thing in our own
human terms. It cannot, in any way, define any of them..."
> Unfortunatly anyone that posts to this list is suceptable to SPAM since
> these message are archived on the web.
> Then again, maybe I'm just starting to get overly paranoid, but I doubt it.
I don't know, fact is that my SPAM statistc shows an increase
of around 5% since I'm on this list - this might be just the
usual SPAM inflation, but taking your guesses, it might also
be list related. (My SPAM statistics are don by my self made
SPAM killer bot - a vcollection of key word filters - the most
usefull filter just triggering '$$$' :)
Gruss
H.
--
Ich denke, also bin ich, also gut
HRK
At 10:19 PM 7/22/98 -0400, you wrote:
>On Tue, 21 Jul 1998 20:56:30, Joe <rigdonj(a)intellistar.net> wrote:
>
>
>> Does anyone have a copy of the Tim Patterson (Seattle Computer
>Products)
>>article series from Byte? I belive that it talked about DOS (...or QDOS or
>>86/DOS...). Thanks.
>>
>>>I may have the original article. What issue was it in?
>
Does anyone know if there was an index published for BYTE? Don't remember
even annual ones in the Dec. issues. I always missed them.
I do have a short one which goes to the end of 1976. Some of my issues are
in boxes where I cannot get to very easily.
-Dave
On Tue, 21 Jul 1998 20:56:30, Joe <rigdonj(a)intellistar.net> wrote:
> Does anyone have a copy of the Tim Patterson (Seattle Computer
Products)
>article series from Byte? I belive that it talked about DOS (...or QDOS or
>86/DOS...). Thanks.
>
>>I may have the original article. What issue was it in?
I don't know. Tim Shoppa mentioned the article series last week, and
since I'm on a DOS 1.1 reverse engineering kick lately, I thought that the
article would be appropriate.
I would guess if Tim Patterson is talking about the predecessor of DOS,
it would be in the late-79 to mid-80 range (hedging by bets a little). I
guess that it could be as late as mid-1981 (based on the introduction of the
5150).
Rich Cini/WUGNET <nospam_rcini(a)msn.com>
- ClubWin/CW6
- MCP Windows 95/Windows Networking
- Preserver of "classic" computers
<<<< ========== reply separator ========== >>>>>
