Hi
Another option on the auto transformer is to use
the primary of a transformer that was designed to
be configured for both voltages. You just ignore
the output leads. The transformer in this case only
needs to be rated for 1/2 the power that you are
sending to the final device. It should be noted that
in der Mouse's diagram, each transformer needs to
be rated for 1/2 the power.
Dwight
>From: "der Mouse" <mouse at rodents.montreal.qc.ca>
>
>> A crude method is to find three biggish AC power transformers all the
>> same. Hook all three secondaries together in parallel, then use one
>> of the primaries as the primary and hook the other two secondaries
>> series-aiding to make the 220 volt 'secondary.'
>
>Just watch your phasing; get the leads swapped to one of the "other
>two" transformers and you'll get (nominal) zero voltage instead of
>double voltage.
>
>Indeed, you can do something autotransformerish with only two
>transformers:
>
> ---------------------.
>IN |
> --------+------------|-------------------------------
> | +----+ OUT
> | | | +-------------
> | | | |
> |_()()()()()_| |_()()()()()_|
> _==========_ _==========_
> | ()()()()() | | ()()()()() |
> | | | |
> +------------|----+ |
> +-----------------+
>
>Of course, the three-transformer version produces double voltage that's
>isolated from the input, whereas the above doesn't. Also, you still
>have to watch the phasing; get a winding's leads swapped and you get
>zero voltage instead of doubled voltage.
>
>/~\ The ASCII der Mouse
>\ / Ribbon Campaign
> X Against HTML mouse at rodents.montreal.qc.ca
>/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
>
I found some more free stuff :
- Dataproducts SPG8020-1/2 Impact Matrix Printer Owner's Manual
- Digital Controls DCC 9000 SCSI Switch Owner's Manual
- IBM 5291 Models 1 and 2 Display Station Operator's Guide
- Quarterdeck manifest
Also have some more manuals for sale for 1 euro a piece :
- TRS-80 Micro Computer Technical Reference Handbook
- Datapoint 8603/8605 Processor Product Specification and Hardware
Reference Manual
- Micom Micro800/2 Data Concentrator M822, M824, M828, M8212, M8216
User's Manual
- HP RTE-A Primary System Software Installation Manual (still
shrinkwrapped, loose pages, needs binder)
- HP Manual Update RTE-A Driver Reference Manual, Update Number 4
- HP Manual Update RTE-A Utilities Manual, Update Number 3
- HP 2930 Series Printers Owner's Manual
- Micro Mint DISK-80 Expansion Interface Owner's Manual and Assembly
Instructions
- Digital VMS System Manager's Manual VMS 5.2
-------------------------------------------------------
http://www.oldcomputercollection.com
Free for postage the manual : "IBM 5291 Model 2 Display Station
Maintenance Library". Productnr is SY31-0667-1
Item is located in the Netherlands.
Stefan.
-------------------------------------------------------
http://www.oldcomputercollection.com
Re:
> 1) Things that are mostly schematics.
>
> 2) Things with a large text component that I might want to try to OCR.
> Questions:
>
> a) What resolution should I use for these two things?
For OCR, it may depend on the OCR software, but for almost everything I have
found that 300 dpi and gray-scale (8 bits per pixel) JPEG works best.
Grayscale is definitely better than black-and-white (1 bit per pixel) for
reproduction that is indistinguishable from the original, but for some OCR
software, black-and-white line art (1 bit per pixel) may work better.
> Well, I have written a couple of times about the company next
> door getting rid of their DEC equipment and prints. The
> carnage has begun.
Where is this?
Hi,
I am currently working on a project to replace an existing Westinghouse
PC1100 plc.
I was wondering if you have the PLC programming software to enable me to
open the customers Program CD copy. This would allow me to easily
convert the program.
Would you be so kind as to point me in the right direction. As I am just
about to give up?
Best Regards
Stuart Matthews
Ntec Solutions
01753 528321
No need for hd but need the HD rails, floppy drives and power supply.
I have the model 80 motherboard waiting for a case.
If someone wants the 220AC only PSU for industrial 80/60/65, feel
free to take it. PSU is a big restangular passive cooled with
screened cage cover.
I was advised that to change this 220VAC unit to 115VAC would
not work even I knew what exactly to do just install voltage doubler
circuit.
Cheers, Wizard
posted from the netbsd-vax mailing list
-------- Original Message --------
Subject: VAX 11 -750 rescue in the Chicago area
Date: Wed, 21 Sep 2005 20:13:33 -0500
From: Stan Johnson <stan.johnson at gmail.com>
Reply-To: srj at pobox.com
To: port-vax at netbsd.org
Hi all
In July I posted trying to sale a VAX 11/750. I've
had several people try to buy the machine, but the
sales have fallen thru for various reasons. I originally
thought I had to have the machine sold and gone
by the beginning of aug, but I got an extension to the
end of sept. for the storage space. Unfortunately
the sale that was suppose to move the machine
last weekend has seems to have died. If I don't hear from
the buyer by tomorrow, I ll need to find someone
else to take the machine. So I am starting
now since I am running out of time.
After my original post several people said I was
asking too much money (~$500), but other
people seemed to be interested. Is there
anyone that can pickup a VAX 11/750 at a
location ~40 miles west of Chicago this coming
weekend? If you can pickup the machine this
weekend it is yours. Pay me what you think
the machine is worth, and if you have to spend
the money on a truck to transport the machine
instead, then so be it. I really want to see the
machine saved.
Let me know ASAP. If I get no responses by
Friday, I'll have to make arrangments to have
it hauled away for scrap on Monday. It has to
be out of the storage space by Monday evening.
Following is a list of what is included.
Thanks again for your time, sorry for the
short notice........
stan johnson
Here is what is included;
VAX11-750
including
......Full Set of spares, front panel down to the power supplies,
......Print Set,