19 Jul
2007
19 Jul
'07
11:20 a.m.
Subject: Re: 1966 Mag: Build NE-2 Neon Bulb Computer - scan available
From: ard at p850ug1.demon.co.uk (Tony Duell)
Date: Wed, 18 Jul 2007 23:54:18 +0100 (BST)
To: cctalk at classiccmp.org
> <rant>
> I'll make this vintage computer-oriented. How many people still own
> a working dishwasher/clothes washer with an integral computer that
> was manufactured over 10 years ago? When I first saw a dishwasher
Maytag washer dryer pair, still in use and working fine.
> with computerized control, my reaction was
"What a damned fool thing
> to do--put a computer in the absolutely worst (hot water, caustics,
> steam) environment possible. Now you can't buy them any other way.
Automotive is considerably worse. Hot, humid, large temperature changes,
power system that runs from 6V worst case to 18V with transients higher
and it must work for 5years to be considered passably reliable.
You can see the manufacturer's point. A custom chip
is a lot cheaper to
make than a cam-and-contacts timer. They can put the magic words
cam and contacts have a well known failure mech, wear. Solution build
it more robust, the counter to that is cost.
'computer', 'microprocessor',.
'digital', etc on the panel. And it's
harder to repair if it fails (if a mechanical timer fails, you can fix
it, if the microprocessor fails, you have to buy a new PCB from the
manufacturers, if they don't want to sell you one, you're stuffed).
Most vendors want their product to work because if it doesn't there
are plenty of competitors with something to offer.
Allison
19 Jul
19 Jul
5:47 p.m.
On Thu, 2007-07-19 at 11:20 -0400, Allison wrote:
Also, have you ever tried to buy a replacement cam switch controller,
never mind replace one?
I did get good at repairing Bendix motor controller PCBs though. If it
wasn't the triac (50p) it was the phase controller chip (two quid). Far
better than ?150 for a new board...
Gordon
Subject: Re: 1966 Mag: Build NE-2 Neon Bulb Computer - scan available
From: ard at p850ug1.demon.co.uk (Tony Duell)
Date: Wed, 18 Jul 2007 23:54:18 +0100 (BST)
To: cctalk at classiccmp.org
> <rant>
> I'll make this vintage computer-oriented. How many people still own
> a working dishwasher/clothes washer with an integral computer that
> was manufactured over 10 years ago? When I first saw a dishwasher
Maytag washer dryer pair, still in use and working fine.
>> with computerized control, my reaction was "What a damned fool thing
>> to do--put a computer in the absolutely worst (hot water, caustics,
>> steam) environment possible. Now you can't buy them any other way. 
20 Jul
20 Jul
7:12 p.m.
Also, have you ever tried to buy a replacement cam
switch controller,
never mind replace one?
It's listed in the spare parts lists for the washing machine/dishwasher,
so I assume it's no harder to get than any other (oriignal) spare.
I've never replaced one, as I've always managed to repair them using
contacts raided from power relays, odd bits of metal, and in one case a
new motor (which are pretty generic, actually. In all cases I had to
remove the timer from the washing machine, it was just a matter of a few
screws and a lot ow wires iwth faston (Lucar Spade) terminals. Either
keep a note of what goes where, or refer to the wiring diagam...
In cany case, obtaining and replacing an electronic timer/controller is
no easier.
-tony
19 Jul
19 Jul
8:06 p.m.
On 19 Jul 2007 at 11:20, Allison wrote:
Most vendors want their product to work because if it
doesn't there
are plenty of competitors with something to offer.
That would be great if it were borne out in practice--i.e. there
really was competition for the most reliable product. In fact, most
of the smaller parts are commodities, produced by a third party firm
that probably holds a major market share. Much the same situation
obtains in the automotive market; how many makes does NipponDenso
supply controls for?
Cheers,
Chuck
20 Jul
20 Jul
3:09 a.m.
At 07:20 AM 7/19/2007, you wrote:
I watched some show highlighting junk vehicles from
cuba/venezuela/etc. The narrator seemed amazed that they were on the road.
Most of them looked better than half of my cars and wouldn't turn a single
head in the valley (Alaska). ; )
As far as electronics go...my parents own a 4 plex. There is a crawl space
under some stairs that a lady used. She moved out and didn't want any of
the stuff. The crawl space filled up with water and froze. I literally
thawed an Apple IIe, disk drive, and monitor out of a block of ice. Once
dry it worked fine. It is still operating today.
A while back I hated newer cars because of all the controls and
computers. But after buying a service manual it isn't that bad. If you
want to know and fix everything, take a look at http://www.megasquirt.info/
Grant
Subject: Re: 1966 Mag: Build NE-2 Neon Bulb Computer - scan available
From: ard at p850ug1.demon.co.uk (Tony Duell)
Date: Wed, 18 Jul 2007 23:54:18 +0100 (BST)
To: cctalk at classiccmp.org
> <rant>
> I'll make this vintage computer-oriented. How many people still own
> a working dishwasher/clothes washer with an integral computer that
> was manufactured over 10 years ago? When I first saw a dishwasher
Maytag washer dryer pair, still in use and working fine.
> with computerized control, my reaction was
"What a damned fool thing
> to do--put a computer in the absolutely worst (hot water, caustics,
> steam) environment possible. Now you can't buy them any other way.
Automotive is considerably worse. Hot, humid, large temperature changes,
power system that runs from 6V worst case to 18V with transients higher
and it must work for 5years to be considered passably reliable.
7:23 p.m.
A while back I hated newer cars because of all the
controls and
computers. But after buying a service manual it isn't that bad. If you
want to know and fix everything, take a look at http://www.megasquirt.info/
Hmmm.. I have the workshop manual for my father's new car -- all 11
volumes of it. Said car has about 10 'ECUs' (Electornic control units)
interconnected by a pair of CAN buses.
Yes, I can follow the manual. I can plug the diagnotic tester into the
socket under the dashboard, see what it says is wrong. Then follow the
proceure in the book -- check the resistance between point A and point B,
check the voltage on this pin, and so on to see if it's the sensor (more
likely) or the ECU input at fault. And I can change the appropriate bit.
But I don't really understnad just what is going on in the same way that
I understoof the old distributor, carburettor and automatic gearbox valve
block. And I can't really repair the units, they are full of custom and
house-marked components.
Now can I do this sort of thing at the roadside if said car breaks down.
I could trace faults in the older systems using little more than a brain
and a test lamp (which if I didn't have, I'd 'borrow' from a dashboard
warning lamp or similar).And even if I could find the fault, I have a lot
mroe chance of 'bodging' an older car than this thing...
-tony
8:18 p.m.
Regardless of what the automotive people say about repairability, I
submit that modern television receivers aren't made to be repairable.
If it were otherwise, you'd be able to find people who repair them
for a living.
To be sure, some of the problems described on the giveaway sets sound
fairly simple--e.g. picture and sound suddenly disappear. But even
so, sets less than a year old seem to end up in the waste stream.
Cheers,
Chuck
21 Jul
21 Jul
5:18 a.m.
On 21/07/07, Chuck Guzis <cclist at sydex.com> wrote:
Regardless of what the automotive people say about
repairability, I
submit that modern television receivers aren't made to be repairable.
If it were otherwise, you'd be able to find people who repair them
for a living.
You still can. At least, I did a year or two ago when the (then main)
TV set in the living room went bang. It cost substantially less than
a new set of comparable quality, to repair.
Unfortunately the previous TV I'd had for years, which I had hung onto
just in case, wasn't so lucky. The LOPT had gone, which I knew from
it's diagnostics, and it wasn't 'economic' to repair - i.e. for that
one it was cheaper to buy a new TV.
To be sure, some of the problems described on the
giveaway sets sound
fairly simple--e.g. picture and sound suddenly disappear. But even
so, sets less than a year old seem to end up in the waste stream.
The quantity I see discarded, sat by the rubbish bins, is
disheartening, as are the numbers that end up being kicked around the
local bits of waste ground by the kids. Surely they can't all (have
been) beyond repair, or even faulty?
The local freecycle list gets lots of TV on it, (and CRT monitors..)
so I presume it's mostly down to people 'upgrading' and simply
chucking out their old sets.
Most ridiculous example I spotted was a >40" rear projection set I saw
sat out at the side of the road.. with it's rear hanging off.. ( I was
on my way out to an appointment or I'd have stopped for it, and it was
gone when I came back... ) Now those are still relatively expensive,
so it would probably have made sense even to pay to get it fixed, had
it needed it.
Rob
5:44 a.m.
On 21/07/2007 10:18, Rob wrote:
On 21/07/07, Chuck Guzis <cclist at sydex.com>
wrote:
> Regardless of what the automotive people say about repairability, I
> submit that modern television receivers aren't made to be repairable.
> If it were otherwise, you'd be able to find people who repair them
> for a living.
You still can. At least, I did a year or two ago when
the (then main)
TV set in the living room went bang. It cost substantially less than
a new set of comparable quality, to repair.
You can here in York, too. There are two repairers I know of.
--
Pete Peter Turnbull
Network Manager
University of York
4:48 p.m.
Regardless of what the automotive people say about repairability, I
submit that modern television receivers aren't made to be repairable.
THankfully I've not had one on my bench yet, but I am told that the
flat-panel TVs (both plasma and LCD) are repaired by board-swapping. The
so-called service manual includes no scheamtics, or even details of the
signals between PCBs. Just a fault-finding chart of the form 'for
fault <foo? replace this module, then this module, then... until it works
again'. And of course it's all large custom ICs that you have little hope
of deciphering.
Ouch. Not only (as you know) do I disaprove of replacing plenty of good
components when some simple part has failed, but also it maens the
manufactuers can effectively make repair impossible after a certain time
by no longer supplying any replacement PCBs.
If it were otherwise, you'd be able to find people
who repair them
for a living.
There is also the fact that TVs (and other thigns) are too darn cheap....
-tony
22 Jul
22 Jul
2:58 p.m.
On Friday 20 July 2007 20:18, Chuck Guzis wrote:
Regardless of what the automotive people say about
repairability, I
submit that modern television receivers aren't made to be repairable.
If it were otherwise, you'd be able to find people who repair them
for a living.
Having been there and done that in the past, it's not the repairability of
the sets, its the economics of running a service business and the amount of
money that you need to charge to stay in business vs. the cost of simply
replacing it with a new one. _That_ is what killed it for me...
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
6:11 p.m.
On 22 Jul 2007 at 14:58, Roy J. Tellason wrote:
Having been there and done that in the past, it's
not the repairability of
the sets, its the economics of running a service business and the amount of
money that you need to charge to stay in business vs. the cost of simply
replacing it with a new one. _That_ is what killed it for me...
Roy, one thing occurred to me. What is the current service life
designed for by the major manufacturers? I ask because of a recent
episode with a microwave oven.
We replaced a microwave oven that dated from about 1980 with a newer
one about 4 years ago. The big difference (both were Japanese
brands) is that the oven box in the old one looked to be a very tough
porcelain enamel--almost impossible to scratch. In the newer model,
the coating was a simple baked-on epoxy enamel paint that failed in
less than 2 years. After recoating it a couple of times with ratttle-
can epoxy, I gave up and purchased a new one with a stainless steel
interior. But the oven itself is much lighter and I suspect that the
electronics will not have 20 years of life in them.
Is a shorter service life by design a feature of modern consumer
electronics (and in particular, computer gear)appliances and
automobiles?
Cheers,
Chuck
7:40 p.m.
Chuck Guzis wrote:
On 22 Jul 2007 at 14:58, Roy J. Tellason wrote:
I just read an recent article in eetimes that the target life of new ICs
is 10 years. This is due to metal migration and other (i can't remember
) effects that sub-micron processes exhibit. I guess you should hang on
to all the old gear you can get, because everything built today will be
land-fill in 10 years. I too have that microwave, stainless on the
outside for no apparent reason and a painted interior. The coating
failed after a few years.
Jim Davis
Having been there and done that in the past,
it's not the repairability of
the sets, its the economics of running a service business and the amount of
money that you need to charge to stay in business vs. the cost of simply
replacing it with a new one. _That_ is what killed it for me...
Roy, one thing occurred to me. What is the current service life
designed for by the major manufacturers? I ask because of a recent
episode with a microwave oven.
We replaced a microwave oven that dated from about 1980 with a newer
one about 4 years ago. The big difference (both were Japanese
brands) is that the oven box in the old one looked to be a very tough
porcelain enamel--almost impossible to scratch. In the newer model,
the coating was a simple baked-on epoxy enamel paint that failed in
less than 2 years. After recoating it a couple of times with ratttle-
can epoxy, I gave up and purchased a new one with a stainless steel
interior. But the oven itself is much lighter and I suspect that the
electronics will not have 20 years of life in them.
Is a shorter service life by design a feature of modern consumer
electronics (and in particular, computer gear)appliances and
automobiles?
Cheers,
Chuck
7:51 p.m.
On Sunday 22 July 2007 19:40, davis wrote:
I just read an recent article in eetimes that the
target life of new
ICs is 10 years. This is due to metal migration and other (i can't
remember ) effects that sub-micron processes exhibit. I guess you
should hang on to all the old gear you can get, because everything
built today will be land-fill in 10 years. I too have that microwave,
stainless on the outside for no apparent reason and a painted
interior. The coating failed after a few years.
"Target life-time" doesn't mean that every one of the chips will be dead
in 10 years. Realistically, at worst, 1/2 will be dead in 10 years,
and more likely than not it'll be somewhere more favorable on the bell
curve than that [an insignificant amount of dead chips until 10 years
out]. There's plenty of products that were produced 20+ years ago
which had worse "target life" (though not all of it had anything to do
with design).
Of course, depending on the product, I'm sure they might have much
longer than 10 year lifetimes... especially in markets like military,
aerospace, marine, etc.
Pat
--
Purdue University ITAP/RCAC --- http://www.rcac.purdue.edu/
The Computer Refuge --- http://computer-refuge.org
7:52 p.m.
I just read an recent article in eetimes that the
target life of new ICs
is 10 years. This is due to metal migration and other (i can't remember
) effects that sub-micron processes exhibit.
This is not really that big of news. When I have asked some chip guys
I know, they have all said the same thing - all ICs will eventually
fail due to migrations. As the geometries shrink, the lifetimes
shorten. Even with the older chips with relatively large geometries,
time is ticking away. 100 year old working ICs may never exist.
But then, tubes are in the same boat. They will all go gassy eventually...
I guess you should hang on
to all the old gear you can get, because everything built today will be
land-fill in 10 years.
Recycle!
--
Will
23 Jul
23 Jul
3:44 a.m.
William Donzelli wrote:
Anyone know how much that buys you in the grand scheme of things? It uses
resources to move dead devices around, strip them to component parts, then
move things like PCBs elsewhere for final materials reclaimation -
particularly if the scheme involves something really dumb like shipping them
by boat halfway around the world. I suspect the recycling step can actually be
more harmful than burying the old thing locally and building a replacement
I guess you
should hang on
to all the old gear you can get, because everything built today will be
land-fill in 10 years.
Recycle! from (local) raw materials.
I can't help thinking it'd be much nicer to simply build stuff that lasts
longer in the first place, and work at educating people about buying products
based on what they actually *need* it to do rather than buying something just
because it's new and therefore assumed to be better. Maybe make
"repairability" a marketing feature too, along with publicising product
lifespan (see other post).
</soapbox>
cheers
Jules
7:56 a.m.
Anyone know how much that buys you in the grand scheme
of things? It uses
resources to move dead devices around, strip them to component parts, then
move things like PCBs elsewhere for final materials reclaimation -
particularly if the scheme involves something really dumb like shipping them
by boat halfway around the world. I suspect the recycling step can actually be
more harmful than burying the old thing locally and building a replacement
from (local) raw materials.
You have no idea how modern electronics recycling works, do you?
--
Will
5 p.m.
New subject: Recycling (was: 1966 Mag: Build NE-2 Neon Bulb Computer
On Mon, 23 Jul 2007, William Donzelli wrote:
You have no idea how modern electronics recycling
works, do you?
No, I don't.
You pay $25, and they take your broken monitor. Isn't that how it works?
When they let the magic smoke out, how successful are they at reclaiming
it to reuse it in new parts?
Is it possible to remove ALL traces of Windoze from the used parts?
When you empty the bit bucket, what percentage of those bits are still
reusable?
How long do you need to run a harddrive in reverse to reset its odometer?
Will your computer display the satanic messages?
If you use a bidirectional printer port, then when the computer sends
characters to the printer, can the printer send them back to keep the
computer from running out of them?
Are USB coffee cup warmers one of the major causes of global warming?
Has anybody found a REAL use for a Useless Serial Botch port?
If you put your keyboard in the dishwasher, should you disconnect it from
the computer?
How many reliable cycles are there in the life of a computron?
11:35 a.m.
On Monday 23 July 2007 03:44, Jules Richardson wrote:
William Donzelli wrote:
Anyone know how much that buys you in the grand scheme of things? It uses
resources to move dead devices around, strip them to component parts, then
move things like PCBs elsewhere for final materials reclaimation -
particularly if the scheme involves something really dumb like shipping
them by boat halfway around the world. I suspect the recycling step can
actually be more harmful than burying the old thing locally and building a
replacement from (local) raw materials.
I can't help thinking it'd be much nicer to simply build stuff that lasts
longer in the first place, and work at educating people about buying
products based on what they actually *need* it to do rather than buying
something just because it's new and therefore assumed to be better. Maybe
make "repairability" a marketing feature too, along with publicising product
lifespan (see other post).
</soapbox>
The question that comes up in my mind is, why isn't this happening now?
Market forces would seem to be pushing things in the opposite direction...
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
I guess
you should hang on to all the old gear you can get, because
everything built today will be land-fill in 10 years.
Recycle! 
26 Jul
26 Jul
8:34 p.m.
William Donzelli wrote:
But then, tubes are in the same boat. They will all go
gassy eventually...
Well just suck all the air out of them again. :)
--
Will
Other than 300B and a few other classic^H^H^H^H^H^H^Hpro-audio tubes
most are $10 or less.
A few people are trying to re-vacume some very old picture tubes
for some very early TV-Sets.
27 Jul
27 Jul
12:39 a.m.
From: woodelf <bfranchuk at jetnet.ab.ca>
William Donzelli wrote:
Hi
I have soem tubes made in the 1920's that still have a
good vacuum. How much longer should I wait.
Dwight
_________________________________________________________________
http://imagine-windowslive.com/hotmail/?locale=en-us&ocid=TXT_TAGHM_mig…
But then, tubes are in the same boat. They will
all go gassy eventually...
Well just suck all the air out of them again. :)
--
Will
---snip---
1:12 a.m.
From: "Chuck Guzis" <cclist at
sydex.com>
On 26 Jul 2007 at 21:39, dwight elvey wrote:
Yep, but you have to know these are lime getters.
Not all that effective.
Dwight
_________________________________________________________________
Don't get caught with egg on your face. Play Chicktionary!?
http://club.live.com/chicktionary.aspx?icid=chick_hotmailtextlink2
Hi
I have soem tubes made in the 1920's that still have a
good vacuum. How much longer should I wait.
Dwight
Isn't that the whole idea behind a getter?
8:50 a.m.
Isn't that the whole idea behind a getter?
The idea behind the getter is to clean up and gas that might be
trapped in the metal elements during pumpdown. A getter is really not
to clean up gases that sneak in thru the glass metal seals - the
getters just are not that effective, and as any plumber will tell you,
leaks only get bigger.
--
Will
1:10 a.m.
On Friday 27 July 2007 00:39, dwight elvey wrote:
Just because a couple of tubes still work doesn't say anything, without
counting the ones that have failed. I'm sure some ICs from today will
still be working 80 years in the future, but it'll likewise be a very
small percentage.
Pat
--
Purdue University ITAP/RCAC --- http://www.rcac.purdue.edu/
The Computer Refuge --- http://computer-refuge.org
From: woodelf
<bfranchuk at jetnet.ab.ca>
William Donzelli wrote:
Hi
I have soem tubes made in the 1920's that still have a
good vacuum. How much longer should I wait. But then, tubes are in the same boat. They will
all go gassy
eventually...
Well just suck all the air out of them again. :)
--
Will
---snip---
1:58 a.m.
William Donzelli wrote:
But then, tubes are in the same boat. They will all go
gassy
eventually...
Not if you're Chris Welkin, Planeteer and can build your own triodes
from junked bits and pieces on the surface of the moon!
(Does anyone remember that comic strip? That bit above was the
subject of one of the episodes.) Did Welkin have a computer?
Cheers,
Chuck
28 Jul
28 Jul
12:15 a.m.
dwight elvey wrote:
Hi
I have soem tubes made in the 1920's that still have a
good vacuum. How much longer should I wait.
Well all I know is apply filament
voltage slowly with no high voltage
to let the getter heat up and work.
Dwight
Hopefully you'l^H^H^H^Htube live a
good 90 years more.
PS. Only who in 90 years will remember ^H
1:37 a.m.
On 28 Jul 2007 at 0:29, William Donzelli wrote:
That is a old radio myth - it does not work any better
than just
letting the tube do its own thing.
It's probably not a bad idea to limit inrush current, however. A
surgistor will do that trick.
I seem to remember it's also advisable to let mercury-vapor
rectifiers that haven't been used for a long time "cook" without
plate voltage the first time they're used (beyond, that is, the
initial normal warm-up time).
...but then, I'm telling anyone anything they don't already know.
Cheers,
Chuck
1:54 a.m.
From: "Chuck Guzis" <cclist at
sydex.com>
Hi
I've never had a gassy tube restore under any condition.
I have restored filaments with poor emition by running them
at higher voltages for some time.
Dwight
_________________________________________________________________
Don't get caught with egg on your face. Play Chicktionary!?
http://club.live.com/chicktionary.aspx?icid=chick_hotmailtextlink2
On 28 Jul 2007 at 0:29, William Donzelli wrote:
That is a old radio myth - it does not work any
better than just
letting the tube do its own thing.
It's probably not a bad idea to limit inrush current, however. A
surgistor will do that trick.
I seem to remember it's also advisable to let mercury-vapor
rectifiers that haven't been used for a long time "cook" without
plate voltage the first time they're used (beyond, that is, the
initial normal warm-up time).
...but then, I'm telling anyone anything they don't already know.
10:44 a.m.
It's probably not a bad idea to limit inrush
current, however. A
surgistor will do that trick.
Limiting inrush is useless for nearly every tube made, as the
filaments are made to deal with it anyway. The only tubes I know of
that required some sort of inrush protection were a few of the very
large transmitting types from the 1940s - the kind whose filament
current ratings are in the hundreds of Amps. Some of them even had
specific power up and power down sequences. With some of the huge
tubes later on, there was inrush protection, but that was to protect
the transformer, not the tube.
I seem to remember it's also advisable to let
mercury-vapor
rectifiers that haven't been used for a long time "cook" without
plate voltage the first time they're used (beyond, that is, the
initial normal warm-up time).
Yes, the dreaded flashover. Every time a mercury rectifier is powered
on, it should go thru the ten-minute (or so) cycle, to make sure ALL
of the mercury is vaporized before high voltage is applied.
As far as I know, computers did not use mercury vapor rectifiers. In
all the ones I have seen, or seen documents for, the rectifiers have
been gas types. When I was recently poking my nose into Pierce's 709
power unit (7mumblefoo?), I saw that IBM used C16J thyratrons - a
whole flock of them. Which probably makes that power unit the most
costly piece to retube these days.
--
Will
1:07 p.m.
On 28 Jul 2007 at 10:44, William Donzelli wrote:
Limiting inrush is useless for nearly every tube made,
as the
filaments are made to deal with it anyway. The only tubes I know of
that required some sort of inrush protection were a few of the very
large transmitting types from the 1940s - the kind whose filament
current ratings are in the hundreds of Amps. Some of them even had
specific power up and power down sequences. With some of the huge
tubes later on, there was inrush protection, but that was to protect
the transformer, not the tube.
Surgistors were very popular in the 50's as either an add-on for TV
receivers or as part of the original chassis.
As far as I know, computers did not use mercury vapor
rectifiers. In
all the ones I have seen, or seen documents for, the rectifiers have
been gas types. When I was recently poking my nose into Pierce's 709
power unit (7mumblefoo?), I saw that IBM used C16J thyratrons - a
whole flock of them. Which probably makes that power unit the most
costly piece to retube these days.
I don't know about the 1600 volt supply for the Univac Solid State
machines for the clock output stage. That might be a possibility,
but I can't find a reference. Weren't some mercury vapor thyratrons
used to drive some printer and punch coils in the early systems?
Cheers,
Chuck
1:23 p.m.
Surgistors were very popular in the 50's as either
an add-on for TV
receivers or as part of the original chassis.
Filled with the finest snake oil available...
I don't know about the 1600 volt supply for the
Univac Solid State
machines for the clock output stage. That might be a possibility,
but I can't find a reference. Weren't some mercury vapor thyratrons
used to drive some printer and punch coils in the early systems?
It is entirely possible.
I would like to find more references to find out exactly what tubes
were used in specific equipments, but for various reasons, that
project has stalled.
--
Will
2:38 p.m.
William Donzelli wrote:
A lot of TV's from around that period or a little later used selenium
rectifiers directly off the line (no power transformer) with a fair whop of
capacitance in the filters (very low impedance on both sides of the
rectifier). I'm guessing, but surgistors might have been used to limit initial
charge current, rather than for the sake of the filaments. Selenium rectifiers
have more ON-resistance than silicon diodes but I'm not sure if it was enough
to save the junctions in such circumstances.
Surgistors were very popular in the 50's as
either an add-on for TV
receivers or as part of the original chassis.
Filled with the finest snake oil available...
29 Jul
29 Jul
2:30 p.m.
On Saturday 28 July 2007 14:38, Brent Hilpert wrote:
William Donzelli wrote:
A lot of TV's from around that period or a little later used selenium
rectifiers directly off the line (no power transformer) with a fair whop of
capacitance in the filters (very low impedance on both sides of the
rectifier). I'm guessing, but surgistors might have been used to limit
initial charge current, rather than for the sake of the filaments. Selenium
rectifiers have more ON-resistance than silicon diodes but I'm not sure if
it was enough to save the junctions in such circumstances.
I remember having an assembly consisting of a pair of those, rated at 500mA
(you could tell by size :-), and a couple of 100uF caps, which in those
days was a pretty big cap, in a voltage-doubler configuration. I probably
salvaged it out of some old TV...
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
Surgistors were very popular in the 50's as either an add-on for TV
receivers or as part of the original chassis.
Filled with the finest snake oil available...
3:13 p.m.
On 29 Jul 2007 at 14:30, Roy J. Tellason wrote:
I remember having an assembly consisting of a pair of
those, rated at
500mA (you could tell by size :-), and a couple of 100uF caps, which
in those days was a pretty big cap, in a voltage-doubler
configuration. I probably salvaged it out of some old TV...
You used to be able to find them in everything from battery chargers
to HO train set power supplies to TVs. They didn't make much of a
splash in AM radios, particularly the "All American 5" variety.
I still have the stink of hydrogen selenide from those things etched
into my brain (when they went bad). Like hydrogen sulfide but more
pungent--and more toxic.
When you replaced them with silicon diodes in HV supply applications
(IR used to offer complete clip-in cartridge diode assemblies), it
was customary to include a small-value series resistance.
Apparently, seleniums were better able to handle the surge from the
usual pi-section filter where the input capacitor was fairly large
(40-50 mfd).
Older battery chargers used copper-oxide rectifiers as well as Tungar
bulbs.
Cheers,
Chuck
4:02 p.m.
On Sunday 29 July 2007 15:13, Chuck Guzis wrote:
I still have the stink of hydrogen selenide from those
things etched
into my brain (when they went bad). Like hydrogen sulfide but more
pungent--and more toxic.
I'm not sure about the chemical involved, but that "toggle switch light
dimmer" mentioned in the other post started out with a small selenium
rectifier, until I overloaded it. No, there's no forgetting _that_ smell!
When you replaced them with silicon diodes in HV
supply applications
(IR used to offer complete clip-in cartridge diode assemblies), it
was customary to include a small-value series resistance.
This was also done when you'd take the base off an old tube and make a
rectifier using silicon. Sometimes. I did that in an old tube scope one
time, and didn't bother.
Older battery chargers used copper-oxide rectifiers as
well as Tungar
bulbs.
I remember lots of references to copper oxide rectifiers, but don't remember
actually ever seeing one. My grandfather had a battery charger that used a
Tungar bulb. As with a lot of other stuff he had, and elsewhere, I got
into it and took it apart to find out what I could. :-)
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
7:58 p.m.
From: "Roy J. Tellason" <rtellason at
verizon.net>
---snip---
I remember lots of references to copper oxide rectifiers, but don't
remember
actually ever seeing one.
Hi
The only time I've seen these are for meter rectifiers. Low current, low
voltage.
Dwight
_________________________________________________________________
Local listings, incredible imagery, and driving directions - all in one
place! http://maps.live.com/?wip=69&FORM=MGAC01
28 Jul
28 Jul
1:37 p.m.
On Sat, 28 Jul 2007 10:07:55 -0700, Chuck Guzis wrote:
I don't know about the 1600 volt supply for the
Univac Solid State
machines for the clock output stage. That might be a possibility,
but I can't find a reference. Weren't some mercury vapor thyratrons
used to drive some printer and punch coils in the early systems?
Cheers,
Chuck
Here are a few links, I found ....
Univac I - "130 tubes (2050 thyratrons), when fired, drove the hammers to print the
characters in the
blockette of tape data. "
http://tinyurl.com/2n66zf
http://tinyurl.com/2jspp3
"Where I came from, Thyratrons were gas-filled (Argon,
if I recall correctly), and the mercury ones were called Ignitrons,
although that may have only been GE's trade-name for them.
A line-printer I used to have (from the Univac SS-90) used
thyratrons for the hammer drivers. I still have a 6-volt
battery-charger with an ignitron."
"Nike Ajax which was designed in 1946-1951..."
http://tinyurl.com/2yyrfo
later
The other Bob
2:07 p.m.
On 28 Jul 2007 at 13:37, Bob Bradlee wrote:
(...links...)
I'd still love to know what the rectifiers in the USS machines were,
although I suspect they were something like 3B28's (xenon gas-
filled).
Cheers,
Chuck
3:36 p.m.
William Donzelli wrote:
They're both gas-filled power-control devices performing similar functions.
From the tinyurl:
"Where I came from, Thyratrons were
gas-filled (Argon,
if I recall correctly), and the mercury ones were called Ignitrons,
although that may have only been GE's trade-name for them.
Ignitrons are very different beasts from thyratrons.
4:21 p.m.
Ignitrons are
very different beasts from thyratrons.
They're both gas-filled power-control devices performing similar functions.
7:15 p.m.
William Donzelli wrote:
Mmmm...sort of. After a few beers.
Thyratrons can contain gases or mercury (or I think, in some case,
both), and they still use a filament, much like a normal tube
(pliotron or kenotron, if any GE people are keeping score) and some
sort of grid for control, although in many thyratrons the grid looks
nothing like a grid. Thyratrons are used for control rather than
rectification, although one can rectify with them (IBMs power supply
for the 709 - they were likely used to give some sort of help in
regulating the DC output).
Ignitrons use mercury (I have never heard of one that does not,
although krytrons are pretty similar) and do not have filaments. The
conductor is the mercury plasma created by the igniter arc, and
conduction is more or less the arc between the pool and the anode.
Ignitrons tend to be used more for rectification than control(and when
used for control, they tend to be simple on-off, rather than the more
sophisticated setups thyratrons are often see with).
Not 'sort of', and one doesn't need beer to see their similarities. They are
sub-classes of a common class; yes, there are differences, otherwise they
wouldn't have different classification names, but the fundamental principle of
using ionized gas to reduce conduction losses is the same. They are both
triggerred on-off devices and ignitrons were used very much in
controlled-rectification applications, their switching speed is actually
reasonably fast ("usually less than 50uS"), making them fine for control in
60Hz systems, as with thyratrons. They are typically discussed in the same
section in textbooks. They perform similar or nearly identical *functions* -
their final *application* may typically differ due to different specs (notably
higher current capacity for ignitrons), although I would suggest there are
areas where their final application could cross over.
To quote from a reference at hand: "The great advantage of the high-current
and overload capacity of the mercury pool has been combined with the control
versatility of the thyratron in the ignitron."
Ignitrons
are very different beasts from thyratrons.
They're both gas-filled power-control devices performing similar functions.
22 Jul
22 Jul
8:03 p.m.
davis wrote:
I just read an recent article in eetimes that the
target life of new ICs
is 10 years. This is due to metal migration and other (i can't remember
) effects that sub-micron processes exhibit.
Forget ten; apparently one well-known chip manufacturer quoted three years at
us the other week for their latest generation of devices. I believe that's
three years whether the thing's on or not too - natural decay of the IC, not
something brought about by it being powered.
because everything built today will be land-fill in 10
years.
Wonderful, isn't it? And people wonder why I don't like modern technology...
8:17 p.m.
Forget ten; apparently one well-known chip
manufacturer quoted three years at
us the other week for their latest generation of devices. I believe that's
three years whether the thing's on or not too - natural decay of the IC, not
something brought about by it being powered.
What "well-known chip manufacturer"? I find it hard to believe three
years as a target...they would be forcing themselves out of many, many
markets, effectively shooting themselves in the foot.
--
Will
8:38 p.m.
William Donzelli wrote:
Damn sure, As senior bottle washer and code monkey for a small display
manufacturer, I would like to know what company is stupid enough to
quote 3 years.
Jim Davis.
Forget ten;
apparently one well-known chip manufacturer quoted three
years at
us the other week for their latest generation of devices. I believe
that's
three years whether the thing's on or not too - natural decay of the
IC, not
something brought about by it being powered.
What "well-known chip manufacturer"? I find it hard to believe three
years as a target...they would be forcing themselves out of many, many
markets, effectively shooting themselves in the foot.
--
Will
23 Jul
23 Jul
3:31 a.m.
davis wrote:
William Donzelli wrote:
Damn sure, As senior bottle washer and code monkey for a small display
manufacturer, I would like to know what company is stupid enough to
quote 3 years.
Why is it so surprising? In the portable device arena, where the 'average'
person changes their gadgets every couple of years for ones with the latest
features, it's the vendors who are dictating ever-smaller, ever-faster chips
which necessitate the higher densities. They don't care if the thing dies in
three years. In fact, that works entirely in their interest as, providing
everybody's doing it (which they are it seems), it means they sell more
product than they would otherwise. Call it a good incentive for consumers to
upgrade.
I believe the three year stuff hasn't left the lab yet (and I suspect it
doesn't matter which chip manufacturer you go to - the densities involved mean
that's the sort of lifetime you get; it's not a by-product of the
manufacturing process used being 'wrong' in some way), but it's where things
are heading for the 'next generation' of compact, portable equipment.
Now, I don't much care for portable gadgets myself anyway - I wouldn't use a
phone to play music or access the 'net for instance, so I can get away with an
older model which hopefully has higher design lifetime. What worries me though
is the trend for other devices to follow the same "smaller, faster" design
parameters and with the prices falling through sheer numbers sold making them
commodity items. How long before it's acceptable for a laptop* or a home DVD
player to need replacing every three years?
* On the business side, that's probably getting close to how often they're
swapped out for a newer model anyway :(
What I'd *like* to see is some notion of design lifespan quoted as part of
product marketing - making it a legal requirement if necessary (as I believe
things like crash-test and fuel consumption data is for cars, at least in the
UK). That way at least it'd help raise lifespan as an issue amongst the public
(because let's face it, the average person seems to love throwing money at new
toys every couple of years anyway). The cynic in me says that the politicians
have a vested interest in keeping the corporations sweet by allowing them to
shift as much product as possible, though :-(
Forget
ten; apparently one well-known chip manufacturer quoted three
years at
us the other week for their latest generation of devices. I believe
that's
three years whether the thing's on or not too - natural decay of the
IC, not
something brought about by it being powered.
What "well-known chip manufacturer"? I find it hard to believe three
years as a target...they would be forcing themselves out of many, many
markets, effectively shooting themselves in the foot.
3:51 a.m.
----- Original Message -----
From: "Jules Richardson" <julesrichardsonuk at yahoo.co.uk>
What I'd *like* to see is some notion of design lifespan quoted as part of
product marketing - making it a legal requirement if necessary (as I
believe
things like crash-test and fuel consumption data is
for cars, at least in
the
UK). That way at least it'd help raise lifespan as
an issue amongst the
public
(because let's face it, the average person seems
to love throwing money at
new
toys every couple of years anyway).
In Denmark, many people toss their cellphone every 6 months. This is because
a cell phone is not sold "at cost + profit", but for a ridiculous amount,
often 1 danish crown, about 18 US$ cent!
This price is possible, because the mobile phone companies subsidize the
phones heavily, in order to get the traffic. The phone is then locked to the
company. The only condition for getting the phone at a low price, is that
they will not change phone company for 6 months. After the "binding period"
is gone, the phone can be unlocked softwarewise, and you can change company.
Nico
7:54 a.m.
Why is it so surprising? In the portable device arena,
where the 'average'
person changes their gadgets every couple of years for ones with the latest
features, it's the vendors who are dictating ever-smaller, ever-faster chips
which necessitate the higher densities. They don't care if the thing dies in
three years. In fact, that works entirely in their interest as, providing
everybody's doing it (which they are it seems), it means they sell more
product than they would otherwise. Call it a good incentive for consumers to
upgrade.
Once again, I ask what "well-known chip manufacturer"?
--
Will
22 Jul
22 Jul
9:18 p.m.
On Sunday 22 July 2007 18:11, Chuck Guzis wrote:
On 22 Jul 2007 at 14:58, Roy J. Tellason wrote:
It's quite possible, but not being "on the inside" I really couldn't
say for
sure. I know that an awful lot of stuff has become commodities, with prices
being pressed ever downward, and so it's not surprising to see them cutting
corners in various ways. At least a microwave is one of those few appliances
that's still mostly metal, these days, I don't see them going away from
that any time soon (though it wouldn't surprise me if they did somehow).
Much has changed in manufacturing where it's apparently way more economical to
deal with fewer subassemblies so repairs get more expensive when the price of
those goes up (and I see this happening with cars, too). And then there's
the basic costs of operating a service business, which don't drop -- they
continue to rise, as costs go up, and when it becomes cheaper to buy new
then you lose that chunk of your business.
We did a lot of c64 repairs way back when. When the machine sold for $595 as
it did at first, then a $60 repair bill made economic sense. When they sold
for only $99 (as they did later on), it was a tossup. And that's one of the
things that killed our last business, that combined with the board-swap that
most PC users felt that they could handle themselves as opposed to getting
something fixed by a shop.
I remember the early 8" floppy drives having 3-figure price tags. In those
days they were worth fixing. I never got an 8" alignment disk but I did get
a couple of them that were for 5.25" drives, at $25-50 each, and they were
worth the investment, but these days with 3.5" drives being either tossed
and available for free or maybe $5-6 at most, they're simply not worth
messing with. Same trend, different bits...
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
Having been there and done that in the past,
it's not the repairability
of the sets, its the economics of running a service business and the
amount of money that you need to charge to stay in business vs. the cost
of simply replacing it with a new one. _That_ is what killed it for
me...
Roy, one thing occurred to me. What is the current service life
designed for by the major manufacturers? I ask because of a recent
episode with a microwave oven.
We replaced a microwave oven that dated from about 1980 with a newer
one about 4 years ago. The big difference (both were Japanese
brands) is that the oven box in the old one looked to be a very tough
porcelain enamel--almost impossible to scratch. In the newer model,
the coating was a simple baked-on epoxy enamel paint that failed in
less than 2 years. After recoating it a couple of times with ratttle-
can epoxy, I gave up and purchased a new one with a stainless steel
interior. But the oven itself is much lighter and I suspect that the
electronics will not have 20 years of life in them.
Is a shorter service life by design a feature of modern consumer
electronics (and in particular, computer gear)appliances and
automobiles? 
27 Jul
27 Jul
5:43 a.m.
2007/7/23, Roy J. Tellason <rtellason at verizon.net>:
We did a lot of c64 repairs way back when. When the
machine sold for $595 as
it did at first, then a $60 repair bill made economic sense. When they sold
for only $99 (as they did later on), it was a tossup.
Didn't the new C-64 look somewhat like the Amiga500/600's? -You could
imagine they were less friendly for repairing in a hobbyist/repairman
sense, any experiences there?
9:35 a.m.
From: "from at fu3.org" <fu3.org at
gmail.com>
Reply-To: "General Discussion: On-Topic and Off-Topic
Posts"<cctalk at classiccmp.org>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Subject: Re: 1966 Mag: Build NE-2 Neon Bulb Computer - scan available
Date: Fri, 27 Jul 2007 11:43:45 +0200
2007/7/23, Roy J. Tellason <rtellason at verizon.net>:
_________________________________________________________________
Local listings, incredible imagery, and driving directions - all in one
place! http://maps.live.com/?wip=69&FORM=MGAC01
We did a lot of c64 repairs way back when. When
the machine sold for
$595 as
it did at first, then a $60 repair bill made
economic sense. When they
sold
for only $99 (as they did later on), it was a
tossup.
Didn't the new C-64 look somewhat like the Amiga500/600's? -You could
imagine they were less friendly for repairing in a hobbyist/repairman
sense, any experiences there?
9:53 a.m.
Oops Wrong button
Sorry about that
Dwight
From: "dwight elvey" <dkelvey at
hotmail.com>
_________________________________________________________________
http://liveearth.msn.com
From: "from at fu3.org" <fu3.org at
gmail.com>
Reply-To: "General Discussion: On-Topic and Off-Topic
Posts"<cctalk at classiccmp.org>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Subject: Re: 1966 Mag: Build NE-2 Neon Bulb Computer - scan available
Date: Fri, 27 Jul 2007 11:43:45 +0200
2007/7/23, Roy J. Tellason <rtellason at verizon.net>:
_________________________________________________________________
Local listings, incredible imagery, and driving directions - all in one
place! http://maps.live.com/?wip=69&FORM=MGAC01
We did a lot of c64 repairs way back when. When
the machine sold for
$595 as
it did at first, then a $60 repair bill made
economic sense. When
they sold
for only $99 (as they did later on), it was a
tossup.
Didn't the new C-64 look somewhat like the Amiga500/600's? -You could
imagine they were less friendly for repairing in a hobbyist/repairman
sense, any experiences there?
28 Jul
28 Jul
12:02 p.m.
On Friday 27 July 2007 05:43, from at fu3.org wrote:
2007/7/23, Roy J. Tellason <rtellason at
verizon.net>:
There were two aspects to this. One was the case, including the keyboard
with the different colored keycaps, and that wasn't all that big of a deal
once you got into it. The other was the fact that they kept on changing the
board inside, there being a total of four or five different revisions that
we saw a lot of . Earlier units had differences in the video area, the
on-board 7805 regulator standing up rather than laying down, and similar but
the first three or four revisions were pretty similar. Then they did stuff
like combining the eight RAM chips into two, combining two of the three ROMs
(Kernel anb BASIC if I'm remembering right), and combining the PLA with some
other random logic to cut the parts count, those were a bit more of a PITA
to work on.
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
We did a lot of c64 repairs way back when. When
the machine sold for
$595 as it did at first, then a $60 repair bill made economic sense.
When they sold for only $99 (as they did later on), it was a tossup.
Didn't the new C-64 look somewhat like the Amiga500/600's? -You could
imagine they were less friendly for repairing in a hobbyist/repairman
sense, any experiences there?
2:09 p.m.
2007/7/28, Roy J. Tellason <rtellason at verizon.net>:
On Friday 27 July 2007 05:43, from at fu3.org wrote:
Alright, it seems you still hacked it. -Thanks for feeding my curiousity.
Didn't the new C-64 look somewhat like the
Amiga500/600's? -You could
imagine they were less friendly for repairing in a hobbyist/repairman
sense, any experiences there?
There were two aspects to this. One was the case, including the keyboard
with the different colored keycaps, and that wasn't all that big of a deal
once you got into it. The other was the fact that they kept on changing the
board inside, there being a total of four or five different revisions that
we saw a lot of . Earlier units had differences in the video area, the
on-board 7805 regulator standing up rather than laying down, and similar but
the first three or four revisions were pretty similar. Then they did stuff
like combining the eight RAM chips into two, combining two of the three ROMs
(Kernel anb BASIC if I'm remembering right), and combining the PLA with some
other random logic to cut the parts count, those were a bit more of a PITA
to work on.
6152
days inactive
6162
days old
55 comments
19 participants
participants (19)
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caveguy＠sbcglobal.net -
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