>>
>> From a UK point of view 'motor' as in motor-generator would be
>> taken to
> some form of internal combustion engine.
> I have heard lots of references to 'motor-generators' but never an
> 'engine-generator'.
Well it just depends who you are used to talking to. I am in the UK,
I own some WW2 kit with a brass plate saying 'Air Ministry Engine
Driven Alternator Set'. Another plate says Tangye-Ricardo and another
saying it was built by Tangye Ltd, Birmingham. Ricardo was a south
coast engine design consulting company. It has a two cylinder 3.5
litre diesel engine which runs at 1000rpm, a huge flywheel and a big
alternator with a smaller (about 15 inch long and 15 inch wide) DC
generator on the back to provide the excitation current for the
alternators field coils. The whole thing comes on rolled steel joists
as a frame and is about 10 foot long, 4 foot wide and 5 foot high. I
bought it to drive my ICT mainframe, so it is on topic.
>
> Devices used for AC to DC, DC to AC and voltage conversion using a
> electric motor coupled to a generator would be referred to as 'rotary
> convertors'.
No, when I've talked to people (in the UK) about a rotary converter,
they were talking about a large 3 phase motor wired up with big
capacitors so that it could be started on a single phase supply and
once turning, the other two windings would provide the other two
phases whilst the pulses to the first winding would keep it running
at the right speed. Of course for a 10kVA supply, I would have needed
at least a 30kVA motor as only one phase was actually driving it.
>> It may be European vs US usage, but in the US "motor" almost always
>> means electric motor in this and other contexts. So what you
>
> That tends to be UK usage too. The thing under the bonnet (OK,
> hood) of
> a car is called an 'engine' over here. 'Motor' for that would be very
> uncommon.
I agree, though motor is also used to mean motor car as in Ford Motor
Company, Dagenham or Vauxhall Motors, Luton.
>
> To me, a 'motor generator' is just that. An electric motor driving an
> electric generator, to be used to convert voltage/frequency, etc. A
> 'rotary converter' (or 'Dynamotor; if oyu go back far enough) is a
> simialr thing with common field windings/frame/etc rather than 2
> separate electrical machines with the shafts coupled.
>
>
>> call a "motor-generator" would be here just plain called a
>> "generator"
>
> A 'generator' over here is either just the mechanical-to-electircal
> energy converter or , as you said, a heat engine coupled to such a
> machine. Certainly if you hired a 'generator' (as somebody
> suggested we
> should do for a VCF-type event), you'd expect to get something with
> the
> engine included.
Yes, but generator also means a machine converting a turning motion
into DC. Cars prior to the mid sixties had generators, after that
they have alternators with a bridge rectifier.
> I don't know how common these other term are across the Pond, but an
> 'alternator' is an AC-output geneterator, a 'Dynamo' (short for
> 'Dynamo-electric machine' is a generator, normally DC output, with a
> wound field, and a 'Magneto' (short for 'Magneto-electric machine'
> is a
> genatore with a permanent magnet field. Which means the common bicycle
> dynamo (as it's normally called over here' is in fact a magneto....
I agree with all but the last part. A magneto is a coil mounted next
to a flywheel, the flywheel having a permanent magnet attached which
when it moves past the coil, generates an electrical spike which
drives the spark plug at exactly the right point in the engine cycle
for a two stroke engine, or for a four stroke, one spark is just
wasted, though it would be possible for the magneto to be run off the
camshaft. The Magento was in turn was a big advance on the old hot
tube ignition, but thats another story.
Roger Holmes
ICT 1301
UK101
Apple 2,3,Lisa and Macs
Archival preservation of software
Chuck Guzis cclist at sydex.com
<mailto:cctalk%40classiccmp.org?Subject=Archival%20preservation%20of%20softw
are&In-Reply-To=471ABEF2.50308%40bitsavers.org>
Sat Oct 20 22:16:48 CDT 2007
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________________________________
On 20 Oct 2007 at 19:52, Al Kossow wrote:
> Unless you recover the data, what you have is a physical artifact of a
magnetic
> storage medium. There is absolutely no way to say what, in fact, is even
on it
> until you read it. Bits aren't preserved if they exist on only one
physical medium,
> which you may not be able to recover in the future.
Exactly. I'm starting to see a trend with some brands of floppies
more than 25 years old where the oxide is starting to separate from
the substrate, leading to fouled heads and "see through" tracks.
Mostly on Wabash brand floppies currently, although a few off-brands
such as "Precision" seem to also be showing this behavior.
Time to get 'em archived.
Cheers,
Chuck
________________________________
-----REPLY-----
Agree. I have made disk images of about 400 NorthStar Horizon disks.
I am seeing some percentage of disks which just are not readable any longer.
Fortunately, not too many but it seems like INSUA and other original disks
are the worst.
What I am doing and encourage others to as well is to make disk images of
all of your NorthStar Horizon disks.
Write a one line summary of the contents of the disk into an index and send
the images to Bitsavers.org.
There is a NorthStar Horizon disk image archive at:
http://bitsavers.org/bits/NorthStar/NorthStar_Horizon/
You can send the disk images and indexes to me and I will load them for you.
Don't let your NorthStar Horizon information fade away. Once it is gone, it
is gone for good.
Thanks!
Andrew Lynch
I just noticed that on the Wikipedia talk page for CP/M someone write that
CP/M was released under a BSD-like license in October 2001. Who had the
copyrights at the time to do this?
--
David Griffith
dgriffi at cs.csubak.edu
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?
Available :
1x Dec VSV11 kit. Contains
- boardset M7061, M7062 & M7064
- original joystick
- videocable
- bulkhead/distibution panel
- inetconnect box (switchable between 110/220V), heavy!
- VT100 keyboard
It is a pull from a working machine.
Contact me offlist please.
Sorry to take up the bandwidth...I've gotten no response on direct email...
Brad;
I burned your M9312 proms... give me a shout to arrange shipping.
Jay West
>
>Subject: Re: Predicta?! -> philco computers
> From: "Ethan Dicks" <ethan.dicks at gmail.com>
> Date: Sun, 21 Oct 2007 12:37:06 +1300
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 10/21/07, William Donzelli <wdonzelli at gmail.com> wrote:
>> > I did not look, because I did not think any were left.
>>
>> Talk to hams. RTTY was very popular many years back. Hams never throw
>> anything away.
>
>Until we moved Comms out of the Dome to the new Station, we still had
>an RTTY rig set up for emergency communications. It was used in 2004,
>for certain, when we were between satellite passes and we couldn't get
>a call through on our Iridium phones.
>
>To keep this nominally on-topic, it was one of two 386s in production
>when the dome was still in use - the other was a Dell 386SX-16 working
>as a front-end to our PBX. There was a sign on it warning people not
>to throw it away.
>
>RTTY always sounded like fun, but, despite my Ham ticket, I have yet
>to set up so much as a packet station, let alone something I know less
>about.
>
>-ethan
RTTY is one of the oldest digital modes, Amtor and Clover are newer.
Some of the newest weak signal modes require 500mhz systems
with decent soundcards. Examples are PSK31 and JST65, they work to
the noise level and below.
One of my pet projects is to get somthing like PSK31 working on a
Qbus PDP11 I have fast A/D and D/A needed to do the 22K or better
samples/sec. but the DSP software is a new thing to me. PSK31
translates user text IO at 31.5 baud to a variable length code
and then to something a transmitter can digest (Narrow audio
bandwidth, less than 31hz!). The software to do it on curent
laptops and PCs exist but that's no fun.
Allison
Vince,
I know plenty about your PDP8A and it's use in Kearney & Trecker machine
tools. I fixed these and PDP8E computers for K&T back in the 80's and
continue to do it to this day. I am running one as I write this.
If you want to talk email at riedelec at wi.rr.com
Dave
Riedel Electronics/Telstar
phone: 262-392-3366
fax: 262-392-3971
www.predicta.com
riedelec at wi.rr.com
>> Yes, an S/390 would be really nice (hey, you can even go with linux if
>> you really wanted to) but they seem a
>> a tad too small for me. It also looks too modern IMO.
>
>But Linux on a S/390 would be like Linux on a SGI (unless it was in a
>single LPAR) - it's lacking something.
That's what the "if you really wanted to" part meant. You can run linux on
it if you want but it's a promise you won't be able to fully harness the system.
>> Yes I also know that mainframes were usually designed for databases and the likes
>
>The 360 in System/360 stands for 360 degrees of coverage, meaning the
>machines were made to do all sorts of tasks. Before the workstation
>came into real power, mainframes had a significant portion of the CAD
>and simulation market.
Yeah but the odds of finding a 360 now are pretty slim. Besides, Most homes are not
equipped with three-phase power.
>> but they can still be fun to
>> play with and you gotta admit it's fun showing off those massive IBM hard drives and then telling your friends
>> how much that massive drive can actually store (20-80 megs if more).
>
>Here you will have troubles. The big IBM drives (DASDs) are almost all
>gone. The last of the really huge disks, 3390s, are just about all out
>of service. Just about everything else big, from early times, is gone,
>except for a few anomalies (like the recent 3350s out of Columbus,
>OH).
>
>For big drives, the CDCs seem to have survived the best.
>
>And oddly, old IBM tape drives - the 3420s - can still be found.
yeah, and that's what makes that one system/36 so nice.
Not only do you have the two internal hard drives in the processing unit but included are two tape drives.
I love 3420's. There is something I have always liked about a wall of them just working away. It must
be the cool noises they make.
>> There is no way I will look into a DEC. I have absolutely no knowledge on any of their good old systems (I have
>> never even seen one) and I have always loved IBM systems (yes, criticize me).
>
>DEC systems mostly just make a lot of sense. Try one, you might like it.
So you want me to start off with a VAX?
http://www.nekochan.net/gallery2/d/11127-2/vax11_750.jpg
hmmm, well if that 11/750 is running in a home it might be worth a try.
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