Hi Michael
At 07:49 AM 2/11/2014, you wrote:
>The RICM needs to repair a S603 triple pulse amplifier flip-chip. The
>failed diode is listed as a DEC D-664. The DEC enthusiast cross-reference
>lists show it as a 1N3606. These diodes are nearly impossible to find. Can
>someone recommend a substitution for the 1N3606 diode?
>Michael Thompson
--- The DEC schematic for the S603 does indeed list 1N3606 as equivalent to the D664. I found complete info on the 1N3606 in the GE 1964 Transistor Manual pp.439-446, pp.564-565, p.587. It does have some special processing, including gold doping and controlled forward characteristics. A couple parameters which stood out are:
- Reverse recovery time: 2ns (nanoseconds--some sources show microseconds, woof)
- Forward voltage 0.55Vmax at 0.1mA, 0.67Vmax at 1mA.
Note that some of the online data listed for this part is misleading or wrong.
Though lesser diodes would probably work, no doubt you would prefer to replace it with one at least as good, for the sake of preserving the integrity of the restoration.
Anyway, I found that the 1N3606 is claimed to be available:
Qty-61 shown here. Price is $1.54ea:
http://www.ralphselectronics.com/SearchResults.aspx?criteria=1N3606
This source shows Qty-173 in Irvine, CA:
http://partsearch.area51esg.com/icswdl2.aspx?user=area51&user=area51&part=1…
New Jersey Semiconductor claims Qty-1424:
http://njsemi.com/product-request/
There were other sources, if those don't pan out.
Steve L.
So far not going well. Didn't seem to have any video from the video
board so pulled that which gives me a serial console. Trying to boot from
my emulator gives 4C DEVINACT. If I'm on the correct drive select I get
the error quicker so its seeing the emulator. TK50 is just blinking red
so I can't boot the diag tape. Online seems to say a good cleaning may
fix this.
Next tried to find the diagnostic floppies. Found these (uvax2diag1)
which may be what I want.
http://www.headcrashers.org/comp/rx50/index.html
Get same 4C DEVINACT trying to boot them. Page didn't give PUTR command
used to create images. I tried both with and without /binary.
Does anyone know of known good diagnostic floppy images hopefully with
information on how to write them back to a floppy? I assume the full
diagnostic hasn't shown up so all that is available is the stripped down
customer one.
Also what is the name you give to boot for the hard drive, floppy, and tape?
Manuals seem skimpy on details and this machine doesn't have the show command.
Also I was assuming the bottom drive is the boot drive based on the manuals
I have. Was this normal?
I haven't tried putting the real drive back in and seeing if its bootable.
Since I don't know the password I'll either have to hard shut it down if
it boots or try one of the procedures for resetting the password. Looks
like it is VMS.
Greetings,
I am attempting to cobble together a system and non-system device driver
for OS/8 to allow me to use my new OS/8 DiskServer utility with my -8/M and
its Xebec floppy drives.
I have quite a bit of documentation on these drives (that will eventually
get pushed to bitsavers, if I find more time) but unfortunately, I'm
lacking in software.
Lack of handlers is okay. The instruction manual gives some programming
examples, which is enough to get me started. But it also cites a test
program which is supposed to be run to initialize any new disk.
>From the book:
Test 1: Format Sectors
Function: To format a new disk or prepare a disk for a series of diagnostic
tests. There is no prerequisite for Test 1 which is normally the first test
to be run int he diagnostic sequence.
Test Procedure:
Greetings,
I spent much of the weekend improving my disk server and OS/8 handlers. I
now have some great new features, and it's working well enough for me to
submit to the world. I know there are still issues at present, but I'm
hoping some OS/8 gurus can help debug some of them.
https://github.com/drovak/os8diskserver
I encourage other developers to help each other out (and myself) by
submitting changes to the code base. I'd like to make this as good as
possible for everyone. I'm pretty new to git and GitHub, so please let me
know if I've screwed something up there.
Here's some more notes:
- I'll be releasing an actual how-to guide within the next few days. For
now, the adventurous ones can help beta test it.
- The server has been compiled successfully under Cygwin, Debian on
Raspberry Pi, and OS X Snow Leopard.
- The OS/8 system handlers use some PDP-8/E and later instructions. If
someone wants to help go back through and track these down, we can see if a
more compliant version will still fit in the allotted space.
- The server now uses dumprest/simh .rk05 images exclusively.
- There is a utility to install a new system handler and bootloader on an
.rk05 image. It seems to work fine.
- There is a utility to convert Bernhard Baehr's simulator's format to the
dumprest/simh format. It also seems to work fine.
- The server supports mounting two disk images at once. This requires the
use of the non-system handler which has four entry points. The first two
point to the two that the system handler uses. The non-system handler can
eventually be expanded to support several more disks as well.
- There's definitely an issue present. Running BASIC with a simple test
program halts the computer after 10206. I've not had a chance to further
investigate why.
- PIP and RESORC will likely need to be updated to reflect that the handler
device type supports the same number of blocks as an RK05. This is
described in Appendix B of the OS/8 Software Support Manual.
- The server does its best to check that a disk write will not go outside
the boundaries of the disk.
- The server does its best to verify that a disk read will not overwrite
the system handler
Also, if an OS/8 guru can help me out, I'd appreciate it. Will a read/write
>from SYS: on an RK05 past block 3248 (decimal) succeed? That is, can a read
or write carry over from one side of the platter to the other? After
looking at the RK8E system handler, I would say this is a yes. It looks
like a call to SYS: with a block number of 6260 (octal) is the same as a
jump to the second entry point. However, is this behavior desirable or
needed? I would have expected the two sides to be logically separated in
the handler. My server attempts to do just that by essentially chopping the
.rk05 image in half. If a transfer goes past the end of either half, an
error occurs. However, if this is not what should happen, I can change that.
As always, feel free to email me if you have any questions or comments. If
you have any ideas for how to make my program better in any way, I'd love
to hear them.
Thank you all for your support,
Kyle
----- Original Message -----
> Date: Sun, 09 Feb 2014 10:50:57 -0800
> From: Brad Hodge <brad at bettercomputing.net>
> One other question.. for my TV Typewriter project I am hoping to ape
> either of the two keyboard designs featured in the magazine.. either the
> blue/red keypunch/teletype style keys of the prototype or the custom keys
> with keycaps featured in the Feb 1973 issue. Wondering if anyone knows of
> possible sources for these. ?I think part of my problem is when searching
> ebay i may not have exactly the right words or phrase.. ie. Not sure if
> 'keypunch' is the right term for the keys used in the prototype. I'm
> hoping to make this as close to one of the two featured designs as
> possible so it's important to get the keys right.
>
> Thanks muchly,
>
> Brad
I can't make out the 'normal' keyboard and my issue of September 1973 RE is
mysteriously missing, but I believe the black, red and blue keyboard is from
an MDS key-to-tape unit.
I bought a bunch of those surplus back in the day because the switches were
MicroSwitch magnet/reed switches, ideal for the harsh oil-filled environment
of an industrial data-collection terminal I was building and selling at the
time. I thought I still had one or two but if I do I can't find them in
Chaos Cellar; will let you know if I do find anything.
If you send me a close-up of the other keyboard I might have something that
would be equivalent; I still have boxes of different keytops from the
above-mentioned project.
m
One other question.. for my TV Typewriter project I am hoping to ape either of the two keyboard designs featured in the magazine.. either the blue/red keypunch/teletype style keys of the prototype or the custom keys with keycaps featured in the Feb 1973 issue. Wondering if anyone knows of possible sources for these. ?I think part of my problem is when searching ebay i may not have exactly the right words or phrase.. ie. Not sure if 'keypunch' is the right term for the keys used in the prototype. I'm hoping to make this as close to one of the two featured designs as possible so it's important to get the keys right.
Thanks muchly,
Brad
Sent from Samsung Mobile
>Message: 5
>Date: Sat, 08 Feb 2014 13:17:12 -0500
>From: allison < ajp166 at verizon.net >
>To: General Discussion: On-Topic Posts Only < cctech at classiccmp.org >
>Subject: Re: Re-done HD video on the Osborne 1
>
<snip>
?
>>> readable screen at 80 chars (VS osborne 50 char).
>> OB_nit: 51?? and scrolling to give the effect of reading a newspaper
>> through a little hole in a piece of cardboard
>50 or scroll it was tiny!
52 columns.
<snip>
>> Did they ever release that battery pack?
>> I remember an EARLY interview where Lee was asked about the size and
>> weight for a battery pack.? Lee responded, "How big is your CAR?? The 12V
>> input is not for use while carrying."
>> (Lee had a gold colored Honda Accord at the time; it did not have any
>> non-stock power ports)
>Never did.? Measured it and it was pretty painful at 12V CRT and video board
>ate 40W alone the rest of the system was about 100W.? That meant your portable
>battery was a 18ah gell cell for about maybe an hour or two.? If all the supplies
>were of switch mode it was maybe possible to get it down some but the CRT
>was killer.
This was discussed earlier. I know that Evan K. says that Lee says it was never released, but I have one that I bought in Chicago at a regular computer store -- still have the receipt. It came with a glossy-printed Osborne (blue/grey) manual, so if it was not officially released, they got very close to that. I have pictures and have scanned the manual, which I can send to anyone interested.
The Computer History Museum has?what they call an?"Osborne car adapter" (Cat #102646068) that is also part of the "Powr-Pak".
Bob
?
?
----- Original Message ----- >
> Date: Sun, 09 Feb 2014 08:59:51 -0800
> From: Chuck Guzis <cclist at sydex.com>
>> Does your 7720 have a semi transparent cover? Couldn't tell from pictures
>> online.
>
> I remember that thing--we evaluated one in the 70s. It had an
> interesting intolerance of being out of level--if you raised the end
> farthest from the spinning disk, the servo mech would have fits. We
> stuck with the Shugart SA4000 until ST506-style 5.25" MFM hard drives
> became available. I think we started with the 7MB Rodime model.
>
> Eventually, IMI merged with Onyx--I recall their building on North First
> Street in San Jose bearing the logo "Onyx+IMI"--a singularly
> unimaginative name, I thought.
>
> --Chuck
Nice pictures of the three-platter 7740:
http://www.flickr.com/photos/elliotli/7229124666/in/photostream/
Thanks for the tip, Chuck; if/when I get the 7710 spinning I'll be sure to
check that it's level.
m
