-----Original Message-----
From: Tony Duell <ard(a)p850ug1.demon.co.uk>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Wednesday, July 21, 1999 2:00 PM
Subject: Re: Sun Monitor (UK) (2)
>>
>> What irritates me is that I, who have practiced in this industry for many
>> years as an outgrowth of my hobby, which this was until about twenty
years
>> ago, since most of my earnings were in a different engineering discipline
up
>> to that time, recognize the skinflint syndrome among hobbyists more than
I
>> ever did before.
>
>I am trying to work out what the heck you're doing on classiccmp, since
>your views seem so different to the general idea of the group.
>
>FWIW, yes I am frugal. I'll admit to that. This doesn't make me dishonest
>or a criminal. It doesn't mean I'm an idiot. It just means that for some
>strange reason I prefer using properly made devices (rather than the crap
>down the local PC shop), and that I prefer to keep things running rather
>than to further polute this planet. You can do what you like...
>
>>
>> Those same individuals who lament that vendors won't "document" their
>> products enough to allow their repair (long after their projected
economic
>
>Maybe you're happy with sending a perfectly good device to the landfill
>for want of a few pence in parts. I am not. For that reason I certainly
>moan when manufacturers won't provide proper repair documentation/parts
>(and so far, all you've provided is bogus reasons why they don't).
>
>> life, measured in seconds, not years, has ended twice over) because they
>> (these hobbyists) have no respect for the intellectual property rights of
>> equipment and software vendors, to wit, they use software they "borrowed"
>
>You are lucky I am generally a 'nice guy', or I'd have you in court
>under whichever of libel or slander applies to mailing lists. FWIW I am
>using a totally free OS/tools on this PC. Covered by the GNU license. I
>haven't ripped it off from anywhere. I have a SCO license for PDP11 unix.
>I've got originals of OS-9, TRS-DOS, Apple DOS 3.3, etc, etc, etc. I
>don't make a habit of stealing things.
>
PLEASE! I didn't mean to imply that you are dishonest, or any other
negative thing. I was thinking about someone completely different when I
made the remarks to which I think you are reacting. He does say many of the
same things as you, but for entirely different reasons. I meant no personal
reference to you except in the sense that you do often point to the expense
of a given item. We're all concerned about that to some extent.
You've made your position abundantly clear many times, and, while I don't
share your views in all cases, I understand what you are saying. The only
point of disagreement, in this case, is that the fellow who wants to USE the
SONY monitor he already has, apparently in working condition, has not
indicated he wants to use it in a restoration project, nor does he
apparently want to make any other sort of project of it. Instead he wants
to use it because he already owns it. I wanted to offer a simple and QUICK
way to get there, starting with how to determine whether he can get there at
all with what he's got.
It pains me too to have to toss something because it's taking up valuable
space and I haven't time to fix it before the space is needed. I would
never have ended up in this discussion if I didn't feel it important to
continue to use resources rather than to discard them the moment they become
unfashionable. The way I got here was by trying to give away a bunch of
aging computer hardware which has gotten too space-consuming to warrant my
keeping it. My own evenings and weekends are spent on trying to take a
dozen or so 8" floppy drives and ship them out to people in condition
suitable for their use, since most of them don't have the equipment or the
experience to adjust them to nominal specifications. If I didn't care about
preserving the usefulness of this old hardware, I'd just take off the
boards, unscrew the steel, and collect about $8 per drive as scrap aluminum.
That's certainly more than I get by fixing them and shipping them.
I had no intention of giving any offense with the remarks I made. They were
certainly not directed at you. There are people who will pinch software or
other easily appropriated intellectual property, and they've always been
among us, and probably always will be. I don't believe in making things any
easier than necessary for them.
>
>> and never buy even their most frequently used software tools claiming
that
>> "better" stuff is "free" by which they mean it didn't cost THEM anything.
>
>You're dead right it didn't cost me anything. Now read the GNU Public
>License to find out why.
>
I have read that document and certainly hope they're able to uphold it under
the current commercial trend in the LINUX community.
>
>>
>> They make excuse after excuse for not parting with a dime, yet see it
>> perfectly satisfactory to spend a man-year avoiding an expenditure not
much
>
>Perhaps you could explain what's wrong with learning to do things
>youself. Particularly as few other people seem to be able to do them. In
>general when I've had dealing with other people to do computing tasks,
>the result has been a mess that has taken longer than it would have taken
>me to do it in the first place.
>
There's nothing wrong with pursuing a project for self-education. It's just
not what I perceived the goal in this instance to be.
>
>That's why I've learnt to do so many things myself. It's the same story
>time and time again. I have something that's broken. The so-called
>service agents want to charge me an arm and a leg to so-say repair it (==
>swap random parts until it seems to work). So instead I take it to bits,
>_make_ new parts, get it working, and then attempt to share my knowledge
>with others. And amazingly so many of these so-called 'skilled jobs' that
>should only be attempted by trained professsionals turn out to be dead
>easy to do with the tools I have here.
>
>> larger than the price of a common lunch on hardware or software. While
it's
>> their choice about how they spend their time, if they valued their time
>> because it was of economic value, they'd better understand the situation.
>
>I don't value my time because nobody else values my time :-(. If I wasn't
>fixing old computers, what would I be doing? Watching TV???
>
Frankly, it's curious that you have no commercial application for your
talents. I know a few fellows who claim to know quite a bit about hardware,
software, etc, but who have problems with taking direction, reporting to
work on a schedule, adhering to a schedule in general, and solving the
problem at hand instead of some other related and more interesting problem.
>
>>
>> The fact is, not everyone wishes to run old and obsolete
hardware/software
>> exclusively, and not everyone is, therefore, in the position that they
have
>
>No, but I thought most people on Classiccmp had some interest in old
>computer repair/restoration. Obviously I am wrong (as usual). So the
>simple solution is for me to unsubscribe from the list.
>
Based on what you've said, that would probably be a mistake, but different
people will have different views on what aspect of repair/restoration is of
interest. In the current case, repair and restoration were not the issue.
Seamlessly adapting a fixed-frequency monitor to a multi-sync environment is
the issue. That's probably somewhat off-topic, since it doesn't really deal
with the classic hardware at all. However, since the monitor is "old" and
the problem is old as well, it popped up.
>
>> to fix something because they can't buy one. That's what thrift stores
are
>> for, or even used computer gadget stores.
>
>It's different in the UK. Many charity shops (thrift stores) don't sell
>electrical stuff at all, since all second-hand electrical stuff has to be
>safety tested. The second-hand computer shops that I know about tend to
>sell working stuff not much cheaper than buying it new. So I generally
>dig in the 'untested, spares or repair' bins and get an assortment of
>bits that I know I can fix.
>
I'm unprepared to comment on the situation in the UK, but, since the
individual who initiated this thread is in the UK, perhaps you could contact
him and determine whether he wants a fix or whether he wants an education.
>
>-tony
>
Hello,
I've followed the instructions to the letter for how to netboot a
VAXstation, and stuff happens, but it doesn't seem to do anything..
I turn the VAX on, and break it to the console, and type 'b/100
esa0'. Everything is up and running on my Linux box across the room,
and mopd reports activity. I see this on my console:
[root@kadath fs]# mopd -a -d
mopd: not running as daemon, -d given.
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP DL 8:0:2b:12:84:6b > ab:0:0:1:0:0 len 18 code 08 RPR
MOP DL 0:40:5:5e:df:71 > 8:0:2b:12:84:6b len 1 code 03 ASV
MOP RC 8:0:2b:12:84:6b > ab:0:0:2:0:0 len 54 code 07 SID
This repeats ad nauseum, every 5 minutes or so. This appears in my
syslogs:
Jul 21 19:07:20 kadath mopd[12768]: mopd 2.5.3 started.
Jul 21 19:07:20 kadath mopd[12768]: Initialized eth0
Jul 21 19:07:20 kadath kernel: mopd uses obsolete (PF_INET,SOCK_PACKET)
Jul 21 19:09:53 kadath mopd[12768]: 8:0:2b:11:12:92 (1) Do you have
MOPBOOT? (Yes)
Jul 21 19:10:35 kadath last message repeated 3 times
...and so on. So, my box is seeing request from the VAX, but nothing
happens on the VAX screen. It simply hangs at '-ESA0'. Any idea what's up?
Did I miss some critical step in my massive ignorance? Help would be
greatly appreciated. :)
Thanks.
_______________________________________________________________
Get Free Email and Do More On The Web. Visit http://www.msn.com
Anyone know how to get into the setup on a Honeywell/Bull HDS-5 terminal?
I need to get in and configure the connection so it can be used for an
application other than paper weight. :)
_____________________________________________
Free email with personality! Over 200 domains!
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>
> > I saw a hardcover book from 1957 at the used bookstore, that discussed
> > digital computer circuits, and had chapters on vacuum tube logic circuits,
> > corememory circuits, some transistor circuits, etc. If this is something
> > that someone here is dieing to have, perhaps because you're designing
> > a vacuum tube computer circuit, just let me know and i'll try to get it
> > before someone else does ;)
>
> In fact, my plan is to build a tube computer someday soon. What was the
> title of the book, and how much was it selling for?
>
Well, several people have asked about this book. Its "Digital Computer
components & circuits" by R. K. Richards, 1957, reprinted 1958. He says
its a companion book to his "arithmetic Operations in Digital Computers",
which the bookstore also has, but thats just a general boolean-logic type
of book.
Anyways, the used bookstore wants $15 for it. Perhaps I should see about
photocopying this.
chapters:
1 History & Introduction
2 Diode switching circuits
3 Vacuum tube systems of circuit logic
4 Transistor systems of circuit logic
5 magnetic core systems of circuit logic
6 Large capacity storage: non-magnetic devices
7 Storage on a magnetic surface
8 Magnetic core storage
9 Circuits and tubes for decimal counting
10 Miscellaneous components and circuits
11 Analog-to-digital and digital-to-analog converters
-Lawrence LeMay
Today I hit the jackpot and got a van load of items for only $10 at the
yard. I got Mac's (7) and Powerbooks (2) done 10 years old yet, Next Station
and Next laser printer, two other laser by HP, Inkjets (2), and the best was
SiliconGraphics Indy. I only got the missing the KB, mouse, memory, and
Monitor. I looked at SG's site and they still sell this unit for $2500.
All and all a good day for collecting. John
Hi,
I walked into Radio Shack today, and was delighted to see a row of posters
on their wall with photos of old Radio Shack stores and equipment from the
beginning of the chain to now. They mentioned that the TRS Model 100 was
'the first laptop in the industry'. Is this even marginally true?
--Max Eskin (max82(a)surfree.com)
http://scivault.hypermart.net: Ignorance is Impotence - Knowledge is Power
Does anyone know the approximate value of a TRS-80 MC-10 computer with 4k
RAM, in good condition?
Also, does anyone have any pictures of one?
ThAnX,
///--->>>
-Jason Willgruber
(roblwill(a)usaor.net)
ICQ#: 1730318
<http://members.tripod.com/general_1>
Dang, Dang, Dang!!!
These 13+ hour days really make me lose my mind!
Sorry, all!
"Merch"
--
Roger "Merch" Merchberger --- sysadmin, Iceberg Computers
Recycling is good, right??? Ok, so I'll recycle an old .sig.
If at first you don't succeed, nuclear warhead
disarmament should *not* be your first career choice.
plz see embedded remarks below.
Dick
-----Original Message-----
From: Tony Duell <ard(a)p850ug1.demon.co.uk>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Wednesday, July 21, 1999 2:00 PM
Subject: Re: Sun Monitor (UK) (2)
>> >No normal VGA card (I am not talking about the special ones designed to
>> >work with sync-on-green monitors) has the hardware for sync-on-green. So
>> >programming the card, however you do it, won't produce a sync-on-green
>> >output. That is what your resistor mod is for - to stick sync pulses (I
>> >wouldn't have thought they met the specs either...) on the green signal.
>> >
>> I seem to recall that several of the Brooktree DAC's, almost excusively
<snip>
>> the DAC pins, had the ability to impose negative sync on the green video
as
>> well.
>
>Since monitor video inputs are almost always AC coupled (at least on real
>monitors), you don't need to be able to generate a -ve output.
>
>If you want to use the DAC for this, then either you need to use up part
>of the range of the DAC for the sync pulse (which will reduce the number
>of colours you can get), and find a way of loading the right values into
>the DAC during the sync pulse time, or you need to fiddle the bias
>votlages at that time. Either way it's a pain.
>
I've got a couple of Philips workstation monitors and one from DEC which
aren't AC-coupled, or at least don't tolerate the resistor bias trick I
mentioned before.
>
>But adding an external sync mixer is a lot easier. Using separate syncs
>is easier still.
>
The advantage to using the resistor from composite blanking is that the
frequencies, albeit not the pulse widths, are correct.
>
>> Multiple encounters with this particular task have taught me that this
>> entails a >1K-hour involvement for a specialist who has experience and
all
>> the precise specifications at his disposal, including the unpublished
ones.
>> I have no idea how long it would take someone who knows little about
>> graphics and less about the undocumented features of the display
controller
>> LSI.
>
>Never underestimate what hobbyists can and will do. It may suprise you,
>but often a good hobbyist can easily outperform many so-called
professionals.
>
That's true, but in this case, we're looking for a solution, not an amusing
problem.
>
>I am not suggesting that reprogramming an SVGA card is a good idea if you
>know _nothing_ about video - although you will surely know a lot about
>video by the time you've done it. Just that it's certainly possible.
>
>> >At VHF you may well have problems if you try to make it on stripboard.
>> >Dead-bugging would work. A proper double-sided PCB with a ground plane
>> >would be even better. Decoupling is going to be very important.
>> >
>> >Compare that to inverting a 64kHz signal (less than 1 thousandth of the
>> >frequency) with a 74LS04. You can stick that on stripboard, tag a 0.1uF
>> >capacitor across the power lines for decoupling and expect it to work
>> >first time.
>> >
>> With orderly and precise assembly techniques, the little circuit I
recommend
>> and use will work every time. The transistors are spec'd to 500 MHz and
the
>
>I don't dispute that at all. But RF (and this most certainly is RF)
>circuit construction _is_ an art that not everybody has experience of.
>There is a a lot more to RF construction than components that happen to
>have suitable specs.
>
>There is a well known myth in electronics. It goes like this : Resistors
>have resistance, capacitors have capacitance, inductors have inductance.
>It reality, all components have all 3 properties. So do pieces of wire.
>And while I'll believe in wires without resistance, to have them without
>inductance or capacitance would involve major changes to the laws of
>physics.
>
>So, in fact, you might find that your nice little electrolytic capacitor
>has a very high impedance at 100MHz due to its self-inductance. Not what
>a beginner would expect at all.
>
>Now, all this is 'old hat' to anyone who's done a lot of RF work (high
>speed digital electronics is most certainly RF, BTW). But I've seen
>plenty of so-called designers who have made a mess of it.
>
>I'd have no worries in building this (I've worked considerably faster,
>many, many times).
>
>> >But if the card already supports something near the right rates, it's
>> >worth giving it a go. Maybe the card supports 1024 lines at 60Hz
>> >vertical. Your monitor uses 52Hz vertical (I've seen monitors that have
>> >that, for some odd reason), also at 1024 lines displayed. You probably
>> >could reprogram the card to do that.
>> >
>> I keep forgetting that a major part of the world doesn't use 60 Hz.
!!! )
>
>It's not that at all (FWIW a lot of machines over here do use 60Hz
>vertical rates, or whatever is used in the rest of the world). The reason
>some workstation monitors used strange scan rates was precisely the
>reason you mentioned earlier - the DACs weren't fast enough, so they had
>to slow everything down to get the number of pixels/line that they wanted.
>
>> This means that you have to do your own arithmetic. I've designed and
>
>Which is not hard, provided you remember that #displayed line != #total
>lines and #horizontal displayed pixels != #equivalent pixels/line. There
>are blnking intervals to consider...
>
>> >At these sorts of frequencies it's worth taking care with the layout,
>> >decoupling, etc. After all, ghosting on green (only) is going to look
>> >terrible. I am not saying it can't work. It can. I would also claim that
>> >you could have problems with it.
>> >
>> You'll see it's dirt simple to build one of these that works fine because
>> the switching speed is relatively leisurely, though the Brooktree folks
>> spec'd a 1/2 GHz transistor array. The one I used is spec'd faster than
the
>> CA3227. Like I wrote above, it's likely a 100 KHz version would work
since
>> all it switches is the sync.
>
>Sure.. But none-the-less you are working with a 100MHz video signal, even
>if only to resistively mix it with the sync pulses. And that's where
>problems _could_ start.
>
The combiner is only active well into the blanking cycle. Before the
blanking cycle, and I'm referring to my 5-transistor/2-diode green+sync
combiner, the circuit draws its constant current from ground through one
side of the dif-amp. When sync goes active, it switches to the other side,
which draws current from green video and sinks it into a mirror-controlled
constant current sink. That's why the negative voltage is needed. That
way, the circuit is essentially passive except during blanking. The only
connection to GREEN is through the collector of one of the transistors in
the dif-amp, which is in cutoff when sync is inactive. I admit it may have
imperfections, but it's served many of us well for many years. What's more,
it's easy to build, since the transistor array is a package which serves as
a platform for the diodes and resistors.
>
>> >You seem to think of everything in terms of money. You are totally
>> >forgetting that (a) you'll learn a lot from doing this (or are you in
>> >favour of knowing nothing and letting everybody else do the work). (b)
>> >that some people enjoy doing this sort of thing. (c) that the 20"
monitor
>> >from the PC shop is most likely a cheap/poor design which gives a
>> >marginal picture even when new. That Sony looks like a good design from
>> >the schematics.
>> >
>> . . . and you're assuming that, perhaps like you when you started this
>> stuff, one knows nothing about this stuff. The third time you do this
job
>
>I am not sure I follow you. Of course I knew nothing when I started, but
>I learnt it pretty quickly. And I've used knowledge gained from doing
>things like this to solve problems elsewhere.
>
That wasn't my point at all. I know from your previous writings that you
are a devoted hobbyist and you enjoy very much tinkering with things that
perhaps don't work quite as you'd like in order to learn how to make them do
what you do like. The guy who started this thread, however, at least in my
perception, was concerned about how to get some utility from a very heavy
and difficult to ship monitor he already owns and is unlikely to move
without considerable expense/effort on his part. What I tried to do is find
him a quick and easy, perhaps quick-and-dirty, solution to his particular
difficulty which probably involved a tradeoff between utility, economic
conservation, and space. My solution may not be THE solution, but it's
worked for me and others, so I thought it might work for him as well.
>
>The sure way to learn something is to do it. You can read all the books
>you like, and you _won't_ get the full story.
>
>
>> I remember the monitors we bought for $30K each back in the mid-'80's,
which
>> are comparable in the most superficial way to this GDM1950. The 20"
>> monitors down at the discount have everything superior in almost every
way
>> to the SONY except for the tube. The ones with a SONY tube cost $500
>
>Have you sat down with the schematics and compared them? Looked at build
>quality? Looked at the specs they're supposed to meet for things like
>corner convergence? You'd be amazed.
>
>I've got a PC monitor on my bench at the moment. The fault is an
>open-circuit horizontal driver transformer (not the flyback). Now this
>transformer handles almost no power. There is no other fault that would
>cause it to burn out. No, the reason it failed is that the wire was
>damaged when it was wound (I have unwound it, you see, as I intend to
>rewind it). That's the sort of thing you get on cheap monitors.
>
>> >You seem to be of the opinion that it's not worth learning how to do
>> >something if somebody else (doesn't matter who or where) can do it for
>> >you. This is a strange attitude for a hobby. It also probably explains
>> >the state the computer industry has got into.
>> >
>> Well, if it's an industry, it's not a hobby to everyone, and the state
it's
>> gotten into is PROFITABLE, which means it will be around a while longer.
>
>Profitable != it will be around, alas. Not in this case. What has
>happened is that companies are making a lot of money selling the same old
>stuff. Just finding ways to cheapen it. There is next to no inovation
>going on any more, at least not in the UK.
>
>Oh, there'll still be companies selling computers/software. Whether
>anybody will still be designing them is another matter...
>
>> >Sometime in the future I intend to make a mechanical clock. The
necessary
>> >tools are certainly not cheap. And it's going to cost me around \pounds
>> >100 for the metal, etc to do it. The result will be less accurate than a
>> >\pounds 5.00 quartz clock. So what!
>> >
>> Well, some of us already know enough about how a mechanical clock works
and
>
>Have you made one?
>
>Sure it's trivial to 'count a train' (work out the number of teeth on the
>gears in a clock). Any schoolkid could do that. What is a lot less
>trivial is to make an escapement that runs, carries on running, and keeps
>good time.
>
>There are other things that seem wrong until you've done them, as well.
>Most people think that the holes in clock plates are cylindrical.
>They're not. They're conical - the pivots run essentially on an edge.
>There is a lot of 'slop' when you put a pivot into just one of the
>plates. That's how it should be. A clock with cylindrical holes will
>almost certainly stop at once.
>
>> even how to build one. Of course that's not everybody's goal, but . . .
>
>I don't beleive anyone can claim they can do something until they've
>actually done it. In this case, by taking a piece of sheet brass and a
>length of steel rod and actually making a clock.
>
>-tony
>
<Someone who is very experienced has suggested doing a bulk erase
<on a TK50 tape and using it in a TK70 tape drive! Has anyone
<ever done so and what happened?
Ah, I believe TK50 and TK70 tape is different media (magnetics). That is
why the TK70 can only read TK50 formats.
<I want to decide if a TK70 is the drive for doing backups? It is
<more than twice as fast as a TK50 and the capacity is about
<4 times when a TK70 is used. Also, the "/VERIFY:ONLY"
<switch in BUP works very well taking less than double the
<time as a straight RESTORE.
This is a no brainer, TK70 is better. By then the technology is more
mature and fewer tapes will be needed to backup a large disk.
Allison
