>Message: 7
>Date: Tue, 06 Jun 2023 02:41:56 +0000
>From: John Floren <john(a)jfloren.net>
>Subject: [cctalk] Re: Getting floppy images to/from real floppy disks.
>To: "General Discussion: On-Topic and Off-Topic Posts"
> <cctalk(a)classiccmp.org>
>
>It's funny that luggable power packs come up here as I'm trying to revive my Otrona >Attache... The power supply does nothing on AC input, even after a recapping, so I >thought I'd investigate the "DC Power Option" described in the manual. Unfortunately I >can't find any record that Otrona ever actually *sold* a "DC Power Option", which >would plug into an unpopulated 6-pin Molex connector on the back of the device. >Interestingly, the header inside the power supply labeled "DC Option" is a 7-pin >header, so I'm not sure which pin was "optional" for the external connector!
>
>I'd just replace the power supply wholesale with a little ATX supply or something, but >the machine needs 5V, 12V, -12V, and 15V; the latter is used to power the CRT and >represents a real challenge! I've yet to find anything that outputs all 4 levels at a >reasonable price.
>
>john
>
I have an Otrona Attache 8:16 with the DC option, so it was sold. (I used both the Osborne and the Otrona in Peru, so having a battery option was an advantage.) However, my Attache has the disk drives that both spin up at the same time, and the DC option does not supply enough power to properly spin both drives, so the computer will reboot if you try to read or write anything to disk while on DC!
I’m traveling now, but will open up my Attache and take some pictures for you in a couple of weeks.
Bob
As you know I've recently restored a couple of CP/M luggable
computers. I also have many other machines with floppy disk drives,
3", 3.5", 5.25" and 8"
The machine I connect to the internet with is a more modern laptop
runnng Windows 8.1. Essentially its only interfaces are USB ports.
I would like to be able to :
Download disk images (I assume in .IMD or .TD0 format) and write them
to real floppy disks to use in my old machnes
If possble, for the more common filesystems like MS-DOS or CP/M, be
able to work with these images on the modern PC at the file level. For
example, if I download a CP/M progam as a .COM file I'd like to be
able to put it into a disk image of a Philips P2000C disk, then
transfer that image to a real floppy and put it in a drive on the
Philips machine.
I understand there are designed based on a modern microcontroller that
connecct to a USB port and a disk drive. Software on the PC translates
between the disk image and the accurately-timed pulses corresponding
to flux transitions on the disk. This unit links to a real disk drive,
you run the software and it reads/writes a real disk in said disk
drive.
Now... I can handle a 'scope. I can handle a logic analyser. I can
handle a soldering iron. I can handle an engineer's lathe. I can
rebuld and align floppy disk drives. I can program most 8-bit micros
along with PERQ microcode, PDP11 mahine code, etc BUT I don't have a
clue when it comes to modern PCs, modern microcontrollers or USB
ports.
So what I am asking is for people to describe what to do as in :
Buy this microcontroller board
Buy this blank PCB and solder the components given in the BOM to it.
Download this software and install it by doing this.
Connect a standard floppy drive to this connector
Run the software, specify the disk image file and sit back.
-tony
>>> Doubtful that VW Bug was on the Autobahn at the time, and, while the
>>> . . .
>>> Now, if the Bug had a trailer hitch, it could tow a trailer behind it with
>>> a gasoline or diesel powered generator with sufficient capacity to run
the PDP-8.
>> Are you suggesting some kind of, say, portable computer?
>> Runs, dodging and weaving.
> I'm not sure that you could fit a complete Model 33-ASR Teletype in the
> passenger seat of the Bug. I suppose if the Teletype was removed from
> its stand, it might be able to sit on the seat, and be powered by the
> same generator that runs the Straight-8.
It is truly easy to remove the passenger seat. Just unlatch the adjuster and
slide it forward off of the tracks. Then make brackets (out of the bottom of
an old seat) to mount the base of the teletype to the brackets.
I have known people who mounted equipment that way.
Many/most VW owners did not clean and lube the tracks, so it was often
difficult to slide the seat, and the latch spring did not re-engage. Ralph
Nader mis-represented that as "Of VWs in accidents, 60%? had the seat come off
of the track." The CORRECT statistic was, "Of VWs in accidents, IN WHICH THERE
WAS SEAT DAMAGE, 60%? were the seat came off of the track." Which was, while
still disconcerting and dangerous, trivial to repair by sliding it back on, and
cleaning and lubing the track and latch, with no other damage.
Removing the bottom of the back seat, and replacing it with a piece of plywood
also provides a roomier and more secure base for the payload.
Possibly even with enough room for a portable generator? (I don't know the
power requirements for the machine, but I do know that VW bugs are not very
amenable to trailering.)
Be careful about putting weight on the back seat! VW had the battery under the
back seat, and many owners did not have a cover over the battery to protect
against shorting by the seat springs!
A type 2 VW bus/van, preferably model 215 (with freight doors on both sides),
would be far more suitable. Or one with sunroof?
In some jurisdictions, the DMV would classify ones with any seats in addition
to the driver's seat, as "Station Wagon"!
To get commercial (lower cost) plates for my type 2 VW in Maryland, I had to
submit pictures showing that there were no other seats, and they even kicked
those back until I also included one showing that it did have a driver's seat.
> It'd be really hard to operate the machine while driving, for sure. It'd be
> far worse than messing with a smartphone while driving :-/. But, once
> stopped somewhere pleasant, you could
> actually develop programs using the punched tape reader/punch on the 33ASR.
> It'd definitely be
> an example of early "mobile computing". (Tongue firmly in cheek).
. . . and, if you caravaned/carpooled, other vehicles could carry peripherals.
No reason why we couldn't eventually have mobile computing!
--
Grumpy Ol' Fred cisin(a)xenosoft.com
Hi all,
I have a Sun 3/110 with a faulty video section (hangs at boot when it polls
the FB) and I want to be able to probe and troubleshoot the board. Does
anyone have any tips on how to get at it since it's buried in the VME
chassis. I was thinking of having an extension card made but thought I'd
ask here and see what others have done first. Any thoughts would be
appreciated. Thanks
-Kurt
Anyone on the list have a VT-180 a.k.a "Robin"? I got one for free a while back, but no disks. Wondering if anyone's in a position to make copies of their working disks and mail them to me -- I could have blanks sent, of course. I'm in the SF bay area.
john
List,
I'd rather not put a customer through the throes of sending a 10.5" reel
of tape written on a S/370 mainframe through international shipping.
Anyone in the Barcelona area with the equipment and ability to handle
reading this thing? Besides, I'm up to my ears in work.
Thanks,
Chuck
I have an HP 2875B paper tape drive that I want to interface to. It has
a 50 pin block connector (using well under 1/2 the pins). The connector
manufacturer was Continental.
I have already discovered, the hard way, that it is not a winchester
connector - the pins on the 50 pin Winchester connector I just obtained
via ePay that otherwise fits are too small in diameter and won't make
contact. I *could* increase their diameter using solder - but -- yuck.
The other connectors of this sort I am familiar with that have the same
general overall size and pinout were made by AMP. Does any one know if
the AMP connectors and the Continental connectors would be compatible?
Thanks.
JRJ
FYI: The Ethernet standards dropped support for half duplex connections a few years back, so that if you have something that depends on half duplex links a recent Ethernet switch might not support it.
