> I imagine it's tricky to get 12V out of 11V (say) whilst able
> to deliver enough current to keep a disk spinning (say). Of
> course I'm sure it's been done, I've just not seen published
> details of schematics etc. anywhere before!
The topology you're looking for is SEPIC, single-ended primary
inductance converter. With a SEPIC convertor the input voltage
range can overlap the output voltage.
Cheers,
Lee.
.
___________________________________________________________
To help you stay safe and secure online, we've developed the all new Yahoo! Security Centre. http://uk.security.yahoo.com
Free a Digital LA210 in the south-west of the Netherlands.
There are also a few boxes of new ribbons.
There are a few more printers that will be thrown out so if you are
looking for anything let me know (also some banana boxes full of
unusued ribbons for various printers).
Has to be picked up within +/- 2 weeks.
Stefan.
-------------------------------------------------------
http://www.oldcomputercollection.com
>
>Subject: FM/MFM data separators (was: WD 1793 FDCs for sale)
> From: Philip Pemberton <philpem at dsl.pipex.com>
> Date: Tue, 23 Aug 2005 08:16:24 +0100
> To: cctalk at classiccmp.org
>
>In message <0ILN001WBHXEEOX0 at vms040.mailsrvcs.net>
> Allison <ajp166 at bellatlantic.net> wrote:
>
>> If I can ever scan it there is a design I have (NEC apnote) for a
>> data seperator for FM/MFM that works for any rate and media. Uses
>> a prom and a latch (yes a state machine) to do synthetic PLL. Analog
>> PLLs were causing people too much pain and oneshots perform poorly.
>
>I would love a copy of that appnote - either scanned or photocopied is good
>(if photocopied, I'll scan it and put it online myself). I've seen another
>design that uses a state machine, but couldn't find any info on what it could
>handle or how it worked. It's on
><http://www.simandl.cz/stranky/zxs/zxs_a.htm> if anyone's interested.
That site has a copy of the circuit and the prom contents. It can handle
all modes and rates.
>I'd really like to get my hands on any of the Rockwell/MOS/Synertek
>6502-series appnotes, or anything on the uPD765 or R6765. Also, has anyone
>got any data on the Fairchild 96LS488?
I'd like a scanner.
>> Lacking that if you can find SMC9229 or '39 part that does a lot
>> of the work for you.
>
>*checks Google
>Obsolete and unobtainium. :(
>The datasheet is probably on Bitsavers, but I doubt it's got any real info on
>how the chip works internally. Certainly not enough to reimplement it from
>off-the-shelf parts.
It was never documeted on the fine detail. As to unobtainium, I've managed
to find a few over time on XT and early at class FDC boards. Likely there is
some NOS available somewhere.
Allison
>
>Subject: Re: WD 1793 FDCs for sale
> From: Philip Pemberton <philpem at dsl.pipex.com>
> Date: Tue, 23 Aug 2005 00:18:14 +0100
> To: cctalk at classiccmp.org
>
>In message <430A56EA.2050907 at bellsouth.net>
> Glen Goodwin <acme_ent at bellsouth.net> wrote:
>
>> Not in my experience. Surplus, yes -- pulls, no.
>> I've bought lots of fuses and odd transistors from them
>> without problem.
>
>That's been my experience too - I bought some uPD765 FDCs (actually Rockwell
>R6765s, but effectively the same chip) from them a while back. No trace of
>damage to the pins, no solder on them, still the same length they were when
>the chips left the factory, and still splayed out.
>
>Speaking of the 765s, I still need to build an MFM data separator...
If I can ever scan it there is a design I have (NEC apnote) for a
data seperator for FM/MFM that works for any rate and media. Uses
a prom and a latch (yes a state machine) to do synthetic PLL. Analog
PLLs were causing people too much pain and oneshots perform poorly.
Lacking that if you can find SMC9229 or '39 part that does a lot
of the work for you.
Allison
I am located in OZ but about a 10-12 hour trip away from where this guy
is - I've just fired off an email myself expressing some interest. If I
get what I am looking for I may have to make a trip over there and may
have some capacity to get other stuff.
++++++++++
Kevin Parker
Web Services Consultant
WorkCover Corporation
p: 08 8233 2548
m: 0418 806 166
e: kparker at workcover.com
w: www.workcover.com
++++++++++
-----Original Message-----
From: cctech-bounces at classiccmp.org
[mailto:cctech-bounces at classiccmp.org] On Behalf Of Ashley Carder
Sent: Thursday, 18 August 2005 3:24 AM
To: General Discussion: On-Topic and Off-Topic Posts
Subject: Re: PDP11 stuff in OZ
> -----Original Message-----
> From: Al Kossow <aek at bitsavers.org>
> Sent: Aug 17, 2005 12:30 AM
> To: classiccmp at classiccmp.org
> Subject: PDP11 stuff in OZ
>
> If someone is nearby..
>
> http://www.psych.usyd.edu.au/pdp-11/equip_list.html
If anyone is in Australia and is willing to collect and ship some items
to the USA for me, I will be glad to pay you for your time and effort.
I have attempted to contact the owner of these items but have not
received a response.
I would very much like to have the spare 11/40 CPU set since I have both
a functional 11/40 and 11/35, as well
as a sick 11/35. My 11/40 is part of a historic functional
display of a 1970s timesharing academic computer center and I would like
to be able to have spares to keep it up and running.
If anyone in Australia is willing to help, please contact me off-list at
wacarder at usit.net.
Thanks,
Ashley
************************************************************************
This e-mail is intended for the use of the addressee only. It may
contain information that is protected by legislated confidentiality
and/or is legally privileged. If you are not the intended recipient you
are prohibited from disseminating, distributing or copying this e-mail.
Any opinion expressed in this e-mail may not necessarily be that of the
WorkCover Corporation of South Australia. Although precautions have
been taken, the sender cannot warrant that this e-mail or any files
transmitted with it are free of viruses or any other defect.
If you have received this e-mail in error, please notify the sender
immediately by return e-mail and destroy the original e-mail and any
copies.
************************************************************************
Hi
I've cracked other protocols by connecting another
computer up to monitor the traffic on the serial lines.
I don't think they did anything fancy. Probably the toughest
thing might be determining the CRC,ECC or checksum method
that they use. It would be best if you could simultaneously
monitor both directions with two serial ports but
I just did one direction at a time and then experimented
until I got all the handshake.
You, of course only want to use the input of the monitoring
computer. You could make a snooping connector or as I did.
I just used two easy clips on the exposed connector.
Dwight
>From: "John R. Hogerhuis" <jhoger at pobox.com>
>
>> > From: John R. Hogerhuis [mailto:jhoger at pobox.com]
>>
>> > Does anyone here have knowledge of the protocol used by the DOS6
>> > INTERLNK/INTERSVR utilities?
>> >
>> > Thanks,
>> >
>> > -- John.
>>
>> I have some knowledge about it. What are you looking for?
>>
>> Greg Manuel
>> www.gmconsulting.net
>>
>
>I'm looking for the packet structures and protocol information;
>basically I'm interested in any information that would be required to
>implement my own version of INTERSVR. The intent is to make something
>that would run on a non-DOS platform as an INTERLNK server.
>
>Thanks,
>
>-- John.
>
>
Philip Pemberton wrote:
Speaking of the 765s, I still need to build an MFM data separator...
There's a good detailed one in the Applications Notes that Al K. scanned in
>from the old CDC stuff I loaned him. It has waveshapes, timing, et. Don't
remember if that one had PCB layout in it, but most CDC ANs did. I know a
lot of small companies asked to use it. They were told to do whatever they
wanted with it.
Billy
Ah foo, I'll put it on top as there so much.
I've done a fair amount of business with BGmicro,
never had a problem. Often the prices are wicked cheap.
Allison
>
>Subject: Re: WD 1793 FDCs for sale
> From: Glen Goodwin <acme_ent at bellsouth.net>
> Date: Mon, 22 Aug 2005 18:51:22 -0400
> To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>
>Chris M wrote:
>> ain't most of BGMicro's stuph pulls or whatnot?
>>
>
>Not in my experience. Surplus, yes -- pulls, no.
>I've bought lots of fuses and odd transistors from them
>without problem.
>
>Glen
>0/0
>
>> --- Roger Merchberger <zmerch at 30below.com> wrote:
>>
>>
>>>Rumor has it that J.C. Wren may have mentioned these
>>>words:
>>>
>>>> I saw these browsing around eBay today. IIRC,
>>>
>>>these are used on most
>>>
>>>>of the S100 floppy controllers, are they not? I
>>>
>>>don't know how a good a
>>>
>>>>deal this is, or the availablity though other
>>>
>>>channels, but thought I'd
>>>
>>>>pass them on.
>>>>
>>>><URL:
>>>
>> http://cgi.ebay.com/BRAND-NEW-WESTERN-DIGITAL-ICS_W0QQitemZ7537549267
>>
>>> >
>>>
>>>If you don't need 38 of 'em, www.bgmicro.com has 'em
>>>fer sale at $4.49 each.
>>>
>>>At the auction, you're spending $3.63 each, just for
>>>comparison.
>>>
>>>HTH,
>>>Roger "Merch" Merchberger
>>>
>>>--
>>>Roger "Merch" Merchberger | "Bugs of a feather
>>>flock together."
>>>sysadmin, Iceberg Computers | Russell
>>>Nelson
>>>zmerch at 30below.com |
>>>
>>>
>>
>>
>>
>> __________________________________________________
>> Do You Yahoo!?
>> Tired of spam? Yahoo! Mail has the best spam protection around
>> http://mail.yahoo.com
>>
>>
I recently picked up an HP 12979 I/O extender with some cards and now
I'm looking for manuals. If someone has manuals for any of the
following and could scan them when time permits that would be much
appreciated. (Yes, I did check bitsavers before asking.)
12979A 12979B 12979C I/O Extender
11629-60001 44 BIT GPO (General Purpose Output?)
I can't find any references to this card. Looks like it basically has
a transister (or pair) for each output bit.
12551B Relay Output Register
12554A 16-Bit Duplex Register
12604B General Purpose Data Source Interface
A Pocket Guide to Interfacing HP Computers (5950-8718) contains some
information on these cards.
12661A Digital Voltage Source Programmer
Apparently this would be used to control equipment such as the HP
6131B Digital Voltage Source.
