Subject: It works!
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Date: Fri, 5 Feb 93 21:57:12 CST

Date: Fri, 5 Feb 93 21:57:12 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: It works!

Thanks to help from a large number of you, plus more than a few hours
of time spent unsoldering, searching for chips, and poking around here
and there with my voltmeter, I now have a functional PDP-8/F.  As of a
few minutes ago, I loaded the following trivial program from the front
panel, and it ran as expected:

		CLA
	L,	ISZ	C
		JMP	L
		IAC
		JMP	L
	C,	0

Not very exciting, but it's a big step up from where I've been for the
last six months with this antique.

Of course, I wasn't supposed to be fiddling with the old machine today,
I was supposed to be in Washington talking to the army about my work,
but the airport was fogbound, so I've got free time on my hands until
the fog lifts.
				Doug Jones
				[email-masked]

Date: Sun, 7 Feb 93 00:36:21 EDT
From: [email-masked] (Ethan Dicks)
To: [email-masked]
Subject: Component level repair and logic families

Date: Sun, 7 Feb 93 00:36:21 EDT
From: [email-masked] (Ethan Dicks)
To: [email-masked]
Subject: Component level repair and logic families

I have just completed a test clip so that I can identify individual
chip failures in my large collection of FLIP-CHIP M-series modules.
Now that I know which parts are actually bad, I need to seek out
replacements.  The chips are basically all straight TTL family with
date codes in the late '60s.

What logic families are any of you using to substitute for failed
TTL logic gates?  74xx?  74LSxx?  74HCTxx?  I'd like to use a
newer logic family to save power.  The supplies are linear, so
reduced current draw shouldn't be a problem.  I wouldn't expect to
see any measurable reduction in current unless I replaced more than
5% of the M-series chips, but every little bit counts when you're
running a 6-amp box.

-ethan

Date: Sun,  7 Feb 1993 11:27:44 -0500
From: "Robert E. Seastrom" <[email-masked]>
To: [email-masked] (Ethan Dicks), [email-masked]
Subject: Re: Component level repair and logic families

X-Mailer: InterCon TCP/Connect II 1.1b34
Date: Sun,  7 Feb 1993 11:27:44 -0500
From: "Robert E. Seastrom" <[email-masked]>
To: [email-masked] (Ethan Dicks), [email-masked]
Subject: Re: Component level repair and logic families

> From: [email-masked] (Ethan Dicks) 
 
> What logic families are any of you using to substitute for failed
> TTL logic gates?  74xx?  74LSxx?  74HCTxx?  I'd like to use a
> newer logic family to save power.  The supplies are linear, so
> reduced current draw shouldn't be a problem.  I wouldn't expect to see
> any measurable reduction in current unless I replaced more than
> 5% of the M-series chips, but every little bit counts when you're
> running a 6-amp box.

Actually, you should try to replace 74xx chips with 74xx chips.  The Schottky
low-power chips and the CMOS imitation TTL chips generally speaking can't
drive as many other chips' inputs with their outputs as plain 7400s.  Both
flavors of "new improved" TTL were designed as power savers, so it is
understandable that they aren't as studlY in the output department.  The net
result would be a module that worked fine in your test jig, but was marginal
in a machine - definitely not the sort of thing you want to have kicking
around.

                                   ---Rob

Date: Mon, 8 Feb 93 14:08:02 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: PDP-12 available

Date: Mon, 8 Feb 93 14:08:02 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: PDP-12 available

I got E-mail from Tom Bereiter ([email-masked]) that there is a PDP-12
being auctioned off tomorrow (Tuesday 2/8) at the University of Texas.
Is anyone down there who can get to the auction?  If not, you'll have
to try to convince Tom to go on your behalf.  He is not (emphasize that)
personally interested in old DEC equipment.  He didn't know what a PDP-12
was, and he probably doesn't want to go to the work of hauling the machine
anywhere or boxing the pieces for shipment.

I don't even know what UT campus this is at.

				Doug Jones
				[email-masked]

To: [email-masked]
Subject: Re: Component level repair and logic families
From: [email-masked] (David Schachter)
Date: Mon, 08 Feb 93 10:54:49 PST
Organization: Greenwire Consulting, Palo Alto, CA, USA

To: [email-masked]
Subject: Re: Component level repair and logic families
From: [email-masked] (David Schachter)
Date: Mon, 08 Feb 93 10:54:49 PST
Organization: Greenwire Consulting, Palo Alto, CA, USA

As Mr. Seastrom writes, it is best to do exact replacements: 74xx with 74xx.
But, if memory serves, 74S (Schottky) has about the same drive capability
as plain 74.  Schottky parts are faster, though, so you could have noise
problems.  74LS doesn't have as much drive capability as plain 74; if you
know the fanouts are modest, there won't be a problem.  74HCT is similar.

In summary: stick with 74xx replacements if you can, otherwise, look at the
circuit to decided whether to use 74S or 74LS/74HCT.  Your decision may be
made simpler by the unavailability of some of the older parts!  (Does anyone
still make 74S or plain 74?)

Or you could have a PC fab shop make new boards and stuff 'em with Xilinx
universal parts or PALs/PLAs.... but that's cheating, big time.

					-- David Schachter

P.S. My knowledge may be out of date.  Look in a National Semiconductor,
Motorola, or TI databook for an appendix on cross-family compatibility.

_____________________________________________________________________________
David Schachter                                 [email-masked]
801 Middlefield Road, #8                               CompuServe: 70714,3017
Palo Alto, CA  94301-2916 USA       After 10 am, voice & fax: +1 415 328 7425

To: Douglas W. Jones <[email-masked]>
Cc: [email-masked], [email-masked]
Subject: Re: PDP-12 available 
Date: Mon, 08 Feb 93 21:12:20 -0600
From: Chris Petrilli <[email-masked]>

To: Douglas W. Jones <[email-masked]>
Cc: [email-masked], [email-masked]
Subject: Re: PDP-12 available 
In-Reply-To: (Your message of Mon, 08 Feb 93 14:08:02 CST.)
             <[email-masked]> 
Date: Mon, 08 Feb 93 21:12:20 -0600
From: Chris Petrilli <[email-masked]>

>>>>> On Mon, 8 Feb 93 14:08:02 CST, Douglas W. Jones
>>>>> <[email-masked]> said:

Doug> I got E-mail from Tom Bereiter ([email-masked]) that there is a
Doug> PDP-12 being auctioned off tomorrow (Tuesday 2/8) at the
Doug> University of Texas.  Is anyone down there who can get to the
Doug> auction?  If not, you'll have to try to convince Tom to go on
Doug> your behalf.  He is not (emphasize that) personally interested
Doug> in old DEC equipment.  He didn't know what a PDP-12 was, and he
Doug> probably doesn't want to go to the work of hauling the machine
Doug> anywhere or boxing the pieces for shipment.

I saw it as well, it looks to be a fully equiped unit with several
DECtape drives, and a couple other things.  It's in a BIG rack (full
19").  I'll see if I can snag it tomorrow if it's not going for too much.

Doug> I don't even know what UT campus this is at.

University of Texas at Austin.  They have an auction every couple
months.  There's also an Alliant FX/8 supercomputer, and a PDP-11/34a.

There's also what I think are repackaged 11s, called: Scientific
Microsystems SMX-11 (or something like that).  Anyone know?

Date: Sat, 13 Feb 93 20:06:34 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: MMI 8K memory boards

Date: Sat, 13 Feb 93 20:06:34 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: MMI 8K memory boards

I have 3 MMI 8K omnibus memory boards which I'm trying to decypher.
There are two different versions of the etch, which doesn't help, and
they have a fair number of 74H chips on them, which limits their
ultimate maintainability, but other than that, they look useful.

My problem:  I have no documentation, and the boards have lots of ground
planes, making the etch hard to trace, particularly under chips.  I've
worked out the jumpering for address select, I think, but there's
another group of jumpers that leaves me puzzled.

Here's the problem, in ASCII art form:

|                                                                        |
|       ____  ____  ____  ____   ____    ____   ____      ____    ____   |
|  _   |____||____||____||____| |____|  |____| |____|    |____|  |____|  |
| | |                                   12345678 AB                      |
| | |   ____  ____  ____  ____   ____    ____   ____      ____    ____   |
| |_|  |____||____||____||____| |____|  |____| |____|    |____|  |____|  |
|  _                      FEDC                                           |
| | |               ____  ____   ____           ____      ____    ____   |
| | |              |____||____| |____|         |____|    |____|  |____|  |
| |_|                                                                    |
|_               __||               _||               __||              |
  |             |   |              |  |              |   |              |
  |_____________|   |______________|  |______________|   |______________|

The letters and digits in the above represent the solder-forks for jumpers.

The grouping 12345678 AB is the address select group, as near as I can
tell.  The digits 1 to 8 correspond to fields 7 through 0, respectively,
and the letters A and B correspond to the two fields worth of storage
supported by the board.  You just wire A and B to the pins corresponding
to the fields you want.  That's fine, except for the missed chance to label
the board so that pin 2 corresponds to field 2 instead of corresponding
to field 6!

But, I haven't figured out the FEDC grouping of pins.  Any ideas?
Better yet, does anyone have actual MMI documentation of this board,
in the forms of schematics or a user's guide?

					Doug Jones
					[email-masked]

Date: Sat, 13 Feb 93 20:14:47 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: KM8E documentation?

Date: Sat, 13 Feb 93 20:14:47 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: KM8E documentation?

I've finally got around to putting a KM8E (M837) board in my old PDP-8/F,
and although it's slow going toggling code in from the front panel, I've
done enough to convince myself that the board is at least partly useful.

My problem is that I don't have the schematics and technical specifications
(The latter are typed materials DEC liked to produce to accompany their
drawings).  The board I have doesn't match the maintenance manual in at
least one key particular - the jumper that the manual suggests must be
removed to enable the time-share option was never installed -- I see no
evidence of a factory installed jumper, and the two solder-fork connectors
are in virgin condition.

So, did DEC manufacture M837 boards without the jumper, or am I misreading
the maintenance manual?  In any case, if I had schematics for the M837,
I'd be able to verify my reading of the manual without bothering the net.

					Doug Jones
					[email-masked]

From: [email-masked] (Stephen Quigg)
Subject: PDP-8 software
To: [email-masked] (pdp8-lovers )
Date: Mon, 15 Feb 1993 09:22:36 +1100 (EDT)
Content-Length: 740       

From: [email-masked] (Stephen Quigg)
Subject: PDP-8 software
To: [email-masked] (pdp8-lovers )
Date: Mon, 15 Feb 1993 09:22:36 +1100 (EDT)
X-Mailer: ELM [version 2.4 PL20]
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Content-Length: 740       

 I sent the following to the alt.sys.pdp8 newsgroup but got no replies. Perhaps
someone on the mailing list can help.
--------------------------------------------------------------------------------
	I've had an 8/E for some time now, just sitting in the garage. The only
software I've got is the RIM loader :-) :-). Any one out there have anything
they can send on the net, such as BIN loader, PALIII assembler, FOCAL, BASIC
etc? (Better still, is any of this stuff available anonymous FTP ( I've already
looked on apache.telebit.com; good stuff but I can't use it (yet)).
        The /e has 16KW, a high-speed punch/reader and an ASR-33 teletype. Also
has an A/D and D/A system in the top of the rack.

Thanks in advance.
Steve Quigg. 

Date: Sun, 14 Feb 93 20:13:50 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: Retraction

Date: Sun, 14 Feb 93 20:13:50 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: Retraction

I just discovered that I do have a complete set of KM8-E schematics,
the set that originally came with one of my KM8-E boards, no less!

It's my only set of schematics that's a full-sized original; it keeps
falling out of the binder where I store it, and I've been ignoring it
while I leaf through the half-size photocopies I have of the other
relevant PDP-8/E/F/M schematics!
					Doug Jones
					[email-masked]

Date: Thu, 25 Feb 1993 19:52:22 -0500
From: Jeff Russ <[email-masked]>
To: [email-masked]
Subject: RK05, RX01/Rx02 questions

Date: Thu, 25 Feb 1993 19:52:22 -0500
From: Jeff Russ <[email-masked]>
To: [email-masked]
Subject: RK05, RX01/Rx02 questions

This past week I picked up some RK05, RX01 and RX02 drives that
were used on PDP11 systems.  Are the drives compatible with
PDP8 systems? 

RK05 question:

	I remember hearing that for the RK05 there is a pcb trace
	under an IC that needs to be cut.  Has anyone else heard
	this?  

RX01 questions:
	
	Does anyone have a maintenace manual for the RX01 drives
	and controllers?  I'll pay for copying and shipping.

	What is the proper alignment for the Berg connectors
	when hooking up the drives and the Omnibus controller?
	
RX02 question:

	Will the RX02 drives work with an RX01 disk controller?

----------------------------------------------------------------------------
Jeff Russ				[email-masked]
University Computing Services		PHONE: (812) 855-2733
Indiana University, Bloomington, IN     I want to buy old PDP[4-9] systems.

Date: Thu, 25 Feb 93 20:21:09 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: Re:  RK05, RX01/Rx02 questions
Cc: [email-masked]

Date: Thu, 25 Feb 93 20:21:09 CST
From: Douglas W. Jones <[email-masked]>
To: [email-masked]
Subject: Re:  RK05, RX01/Rx02 questions
Cc: [email-masked]

I have an rx01 maintenance manual.  I'll have a copy made.  The manual has a
page documenting the Berg connector hookup, but it does seem less than clear.
The Rx01 and Rx02 drives work with the same Omnibus interface. The only
difference is at the far end.  The RX01 can be used from either a PDP8 or
a PDP-11, and the manual applies equally to both.

The rule for the cable (a BC05L-15 cable) is that the loop of cable held
by the strain relief should be adjacent to the printed circuit board, and
the cut ends of the ribbon should face away from the printed circuit board.
This prevents bits of conductive flotsom from shorting a trace on the
board to a conductor in the cable.

I have one BC05L cable, and one RX8E board to run my two RX01 units.  If I
could get my hands on another RX8E board, I'd be very happy.

					Doug Jones
					[email-masked]

From: [email-masked] (Meg Geddes)
Subject: Re: RK05, RX01/Rx02 questions
To: [email-masked] (Jeff Russ)
Date: Thu, 25 Feb 1993 21:59:51 -0500 (EST)
Cc: [email-masked]
Content-Length: 578       

From: [email-masked] (Meg Geddes)
Subject: Re: RK05, RX01/Rx02 questions
To: [email-masked] (Jeff Russ)
Date: Thu, 25 Feb 1993 21:59:51 -0500 (EST)
Cc: [email-masked]
In-Reply-To: <[email-masked]> from "Jeff Russ" at Feb 25, 93 07:52:22 pm
X-Mailer: ELM [version 2.4 PL6]
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Content-Length: 578       

->RK05 question:
->
->	I remember hearing that for the RK05 there is a pcb trace
->	under an IC that needs to be cut.  Has anyone else heard
->	this?  

It's been a while, but my remembrance is that the drives are the same
whether they are PDP11 or PDP8, it's the pack that are different (16 bit
vs 12 bit)

->RX02 question:
->
->	Will the RX02 drives work with an RX01 disk controller?

Yep.  RX8E (M8357, I believe)

-- 
Meg Geddes     <No admitted affiliation with anything>     Ann Arbor, MI
[email-masked]

<I have PMS and root password.  Don't mess with me.>

From: Johnny Billquist  <[email-masked]>
Date: Fri, 26 Feb 93 5:30:18 MET
Reply-To: [email-masked]
To: Jeff Russ <[email-masked]>
Cc: [email-masked]
Subject: Re: RK05, RX01/Rx02 questions

From: Johnny Billquist  <[email-masked]>
Date: Fri, 26 Feb 93 5:30:18 MET
Reply-To: [email-masked]
To: Jeff Russ <[email-masked]>
Cc: [email-masked]
Subject: Re: RK05, RX01/Rx02 questions
In-Reply-To: Your message of Thu, 25 Feb 1993 19:52:22 -0500

>This past week I picked up some RK05, RX01 and RX02 drives that
>were used on PDP11 systems.  Are the drives compatible with
>PDP8 systems? 

Yes.

>RK05 question:
>
>	I remember hearing that for the RK05 there is a pcb trace
>	under an IC that needs to be cut.  Has anyone else heard
>	this?  

Doubt it. The RK05 is the same for both pdp8 and pdp11. However! The
disks are hard formatted! You cannot use pdp11 disks for a pdp8.
You'll have to find proper disks somewhere (DEC still sells them. :-)
The -11 disks have 12 sectors/track, the -8 have 16 sectors/track.

>RX01 questions:
>	
>	Does anyone have a maintenace manual for the RX01 drives
>	and controllers?  I'll pay for copying and shipping.

Might have somewhere. I'll have to dig through heaps of stuff though.
Then shipping from Sweden to US costs a lot. Maybe someone a little
closer...

>	What is the proper alignment for the Berg connectors
>	when hooking up the drives and the Omnibus controller?

No idea. Trial and error?

>RX02 question:
>
>	Will the RX02 drives work with an RX01 disk controller?

Again. No idea. Maybe, maybe not. I would like to hear that it work,
since I have some RX8E controllers...

Johnny Billquist                  || "I'm on a bus
CS student at Uppsala University  ||  on a psychedelic trip
email: [email-masked]       ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

Date: Fri, 26 Feb 93 15:15 GMT
From: PJHurst <[email-masked]>
To: pdp8-lovers <[email-masked]>
Subject: jeff russ question

Date: Fri, 26 Feb 93 15:15 GMT
From: PJHurst <[email-masked]>
To: pdp8-lovers <[email-masked]>
Subject: jeff russ question

I sent the following directly to jeff:
Date:     Fri Feb 26, 1993  3:10 am  GMT
From:     PJHurst / MCI ID: 546-0443
 
TO:       Jeff Russ
          EMS: INTERNET / MCI ID: 376-5414
          MBX: [email-masked]
Subject:  RE: RK05, RX01/Rx02 questions
Message-Id: 00930226031000/0005460443PK2EM
 
1) There is no difference on rk05 drives, between pdp11 and pdp8 systems
   the difference lies in the number of sectors on the pack that is in the
   drive 12-sector for pdp11 and 16-sector for pdp8. In the case of 
   rf05f (fixed) the packs can be changed by removing the front cover on
   the drive...
2) rx8e controler cards can run both rx01 or rx02 drives, on the pdp11
   the difference in controler cards happened because of a speed problem
   in the different models of '11's and in actuallity any controler can
   run an rx01 or rx02 with appropriate software, if the processor can
   keep up
3) The dec part number for rx8/rx11 manual is ek-rx01-mm-002 which describes
   rx01 floppy interface and is applicable in most part for an rx02 on an
   pdp8 considering that the only difference is the drive and all else is the
   same...
4) The dec part number for the rx02 manual is ek-0rx02-tm-001 which describes
   rx02 drives and interfaces note that the card for an pdp8 is called
   an rx8e for single density, and rx28 for double density but is in fact
   the same M8357 omnibus interface card.
5) note that in addition to the rx8e/rx28 card, compatable interfaces
   exist for the vt78, decmate I and decmate II pdp8 compatable micro
   computer systems

Hope that this was of some help

Date: Fri, 26 Feb 93 16:35:29 EDT
From: [email-masked] (Ethan Dicks)
To: [email-masked]
Cc: [email-masked]
Subject: Re: RK05, RX01/Rx02 questions

Date: Fri, 26 Feb 93 16:35:29 EDT
From: [email-masked] (Ethan Dicks)
To: [email-masked]
Cc: [email-masked]
Subject: Re: RK05, RX01/Rx02 questions

:>This past week I picked up some RK05, RX01 and RX02 drives that
:>were used on PDP11 systems.  Are the drives compatible with
:>PDP8 systems? 
:
:Yes.
:
:>RK05 question:
:>
:>	I remember hearing that for the RK05 there is a pcb trace
:>	under an IC that needs to be cut.  Has anyone else heard
:>	this?  
:
:Doubt it. The RK05 is the same for both pdp8 and pdp11. However! The
:disks are hard formatted! You cannot use pdp11 disks for a pdp8.
:You'll have to find proper disks somewhere (DEC still sells them. :-)
:The -11 disks have 12 sectors/track, the -8 have 16 sectors/track.

On that note, I have an RK05F 16 sector pack that I have never been
able to read.  The only working drives that I have are RK05J

The pack came with an RK05F that has long since been dismantled.  I
was only 18 and had no experience with RK05 drives.  The company that
gave me the RK-11C, the RK05J and RK05F also had no experience with
RK05s.  I did not have any documentation on how to remove a platter
from an -F.  For reasons that I can't accurately remember, the heads
didn't fully retract and I scagged a 12 sector pack and the drive
trying to remove it :-(  The 16 sector pack was safely put away at
the time.

To make a long story short, I have a RK05F 16 sector pack that I have
no way to read.  It has been in a shipping box for over 8 years, waiting
for a home.  I am willing to give this away to a good home as long
as I can get a copy of the data on it.  I'll even pay shipping.

I do not have any RK05J/16 packs, sorry.

-ethan