>Most heads have two sets of windings. One for trim erase and a second
>for read/write. The organization varies but the trim is two pins or
>have one pin in common with R/W and the RW is often a centertapped
>winding (three wires) so you should see three connections of near
>zero ohms and a pair that are also near zero OR 4 pins that show
>near zero (common wire case).
>
>The test for alignment usually requires a calibration disk and scope
>but I've done it by doing reads of a known good disk and "finding
>the edges" and setting it for the middle. Track 00 is usually less
>critical so if it happens when the head out and you can boot or read
>the disk thats usually good enough.
>
>Allison
Allison - thank you very much. I've measured the replacement heads and it
looks like they may be damaged. There are 5 connections to each head - on
the upper head, 3 connections measure zero, and on the bottom head, 4
connections measure zero. The bottom head is consistent with another head
(damaged) I have. I know that the replacement heads were able to read data,
but caused the tracks to erase when writing, so I still would expect to be
able to use them.
The major question I have, though, is how do you change the position of the
head to calibrate it? On the MPF-52W-30 (sorry I inadvertently gave wrong
number last time) there's a variable pot RV101 and 2 pins to IC101
(CXD1007B) associated with X-adj and X-reset. Other than setting the
position of Track 00, these look like the only options available to move the
heads a fraction of a step.
I'd be grateful for any thoughts or suggestions.
Peter
Anybody want a free Sun? I know the chap offering this personally, as
it happens...
- LP
---------- Forwarded message ----------
From: Roger Burton West <roger+freecycle at firedrake.org>
Date: 22 Jan 2008 14:03
Subject: [FreeCycleLondon] OFFERED Sun Enterprise 450 server and
A-1000 RAID, E13
To: FreecycleLondon at yahoogroups.com
This is not capable of being used as a normal PC.
It's a _large_ Sun server dating from around 1999 (model introduced in
1997). Four 400MHz UltraSparc-II processors, 4GB RAM, no discs on board
but the A-1000 RAID unit has about 100GB in it. No monitor or keyboard.
Solaris 8 installed, but a licence to run it is up to you (or just throw
on Linux or a more recent Solaris).
This is a big and heavy machine - 58cm high, 45cm wide, 65cm deep. It'll
fit in an estate car or a van, but I wouldn't want to try it in a normal
saloon. Loading or unloading is a job for at least two energetic people;
I'll help you at this end.
This is a very nice piece of kit, but I just don't have room for it and
I'd like it out of my life as soon as possible...
Roger
--
Liam Proven ? Profile: http://www.linkedin.com/in/liamproven
Email: lproven at cix.co.uk ? GMail/GoogleTalk/Orkut: lproven at gmail.com
Tel: +44 20-8685-0498 ? Cell: +44 7939-087884 ? Fax: + 44 870-9151419
AOL/AIM/iChat: liamproven at aol.com ? MSN/Messenger: lproven at hotmail.com
Yahoo: liamproven at yahoo.co.uk ? Skype: liamproven ? ICQ: 73187508
I have some stuff that's free for shipping:
Three 10base-FL AUI-to-fiber transceivers
One ISA SCSI card with DB25 connector. It's a PEL 1600 and carries an
Adaptec AIX-63600 chip.
--
David Griffith
dgriffi at cs.csubak.edu
Jay,
I was trying to locate the name of the owner/founder of Western Digital
and came across your note re System Industries disk controller and
Western Dynex drive. I was the VP of Engineering at System Industries
>from 1973 to 1979. The 3040 and 3051 were disk controllers we developed
during that time. As I recall the 3051 was a 3040 with ECC added -
could be wrong. I am still in touch with some of the engineers from
those days who may be able to answer specific question. Let me know.
Jim Patterson mail4jlpatterson at yahoo.com
-----------Original Message:
Date: Mon, 21 Jan 2008 20:47:21 -0500
From: "Peter" <pludikar at sympatico.ca>
Subject: RE: Head alignment for legacy Sony FDD
> 4 shorted together ('measuer 0') and one unconencted one would be what I
> expect.
> The uncconected one will be at one end of the head edge connector
> fingers. On the damaged head, which _other_ one is unconnected ?
On the damaged head, three fingers at one end show shorted. I guess that
means: 3) Other end of the R/W coil, 4) Centre tap of R/W and 5) Erase
Are probably okay. Finger 2) shows o/c - this would be consistent with the
fact that before I managed to fry the drive, the FDD could read data but on
writing I lost all data (ie everything was erased)
>> there's a variable pot RV101 and 2 pins to IC101
>> (CXD1007B) associated with X-adj and X-reset
> Are these related to head alignment? I must say I am rather suprised.
> Normally you physically move the head stepper motor slightly.
There doesn't appear to be a physical way of moving the heads - I was
speculating/hoping that RV101 and the 2 X related pins may have something to
do with fine adjustment - but I have no real idea. The heads are mounted on
a diecast bracket with locating holes. There are corresponding centring
pins on the main diecast body and there's no discernable movement when the
two are mated.
I rigged up a small Shugart type interface board with manual switches that
allowed me to exercise the main drive control (drive select, motor on, step
direction, step etc.). The control logic on the FDD stops the head from
stepping in the down direction once the track 0 sensor is activated. So my
one of my thoughts is that the track 0 sensor actually defines the fine head
position, but I don't know for sure. Any thoughts or suggestions?
-Peter
-----------Reply:
The track 0 sensor defines the track numbers, i.e. which track to start at.
Adjusting where those tracks actually are on the disk is usually done by
rotating the stepper motor; AFAIK there's no way to do that with any non-
mechanical adjustment. I'd leave that as a last resort though; within reason,
neither should affect the drive's ability to write to a *blank* disk and read
those disks, and alignment and track 0 are probably not your issue.
m
Just remembered -- Pertec.
-----Original Message-----
From: "Evan" <evan at snarc.net>
Subj: Re: altair turnkey with internal drives
Date: Tue Jan 22, 2008 1:37 am
Size: 716 bytes
To: "General Discussion: On-Topic and Off-Topic Posts"<cctalk at classiccmp.org>
Maybe some form of the Attache? I forget who made it ... might've been a company with a 'P' in the name that bought MITS? (I'm not at a computer to look it up right now.)
-----Original Message-----
From: David Griffith <dgriffi at cs.csubak.edu>
Subj: altair turnkey with internal drives
Date: Tue Jan 22, 2008 12:59 am
Size: 345 bytes
To: cctalk at classiccmp.org
Has anyone here heard of an Altair 8800 turnkey with internal floppy
drives? I found one in the estate in Pasadena I'm liquidating.
--
David Griffith
dgriffi at cs.csubak.edu
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?
Maybe some form of the Attache? I forget who made it ... might've been a company with a 'P' in the name that bought MITS? (I'm not at a computer to look it up right now.)
-----Original Message-----
From: David Griffith <dgriffi at cs.csubak.edu>
Subj: altair turnkey with internal drives
Date: Tue Jan 22, 2008 12:59 am
Size: 345 bytes
To: cctalk at classiccmp.org
Has anyone here heard of an Altair 8800 turnkey with internal floppy
drives? I found one in the estate in Pasadena I'm liquidating.
--
David Griffith
dgriffi at cs.csubak.edu
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?
Has anyone here heard of an Altair 8800 turnkey with internal floppy
drives? I found one in the estate in Pasadena I'm liquidating.
--
David Griffith
dgriffi at cs.csubak.edu
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?
Hello,
I'm wondering if anyone here is interested in purchasing the following
lot of boards (I count 176) -- the vast majority of these are PDP-11
cards.
I'd rather get rid of them in one lot than eBay them individually and
deal with the hassles.
This inventory is to the best of my knowledge, I would of course physically
verify inventory before we finalized anything.
I am located in Kanata, Ontario, Canada, K2M 1C5 for shipping, and I can
do Canada Post, UPS, or Fedex (Ground or Express).
I am entertaining offers until the end of the month or so; please email
me directly.
Cheers,
-RK
4 M105 Address Selector
2 M234 KE11-A Registers
1 M7071 Waveform Generator
3 M7104 RK05 Disk Controller 1 (data buffer retgister and status)
3 M7105 RK05 Disk Controller 2 (major registers)
3 M7106 RK05 Disk Controller 3 (control module)
1 M7227 Plotter Control
2 M7228 REAL TIME PROGRAMMABLE CLOCK
1 M7263 UNIBUS CPU Module
2 M7264 LSI 11 CPU
1 M7265 KD11E PDP-11/34 Data Path
1 M7266 KD11E PDP-11/34 Control
1 M7270 KD11
1 M7516 DELQA Ethernet Adaptor
1 M7700 Dec Pak Index and Sector
5 M7705 Drive Control Logic
5 M7706 Interface Timing
6 M7707 Servo Control
6 M7708 Track Position Detector / PLO
1 M7710 Print Sequencer
1 M7711 Control Logic A
1 M7712 Control Logic ? (Blotted out, guess "B")
1 M7713 LCV
1 M7714 ?
1 M7715 Line Feed Control
1 M7716 HS50 Motor Translator
2 M7717 Motor Control
1 M7726 Floppy Disk Controller
1 M7727 Read/Write Control
5 M7729 RK06 SERVO ANALOG
1 M7744 RX-02 Floppy Disk Controller
1 M7745 RX-02 R/W Control
1 M780 KL11 U Teletype transmitter & receiver for KL11, 110 baud
2 M7800YA ASYNC TRANSMITTER & RCVR, WITHOUT EIA CHIPS,CURRE
1 M781 PC-11 Control
2 M7810 PC-11 Interface
2 M782 Interrupt Control
4 M7821 Interrupt Control
2 M783 Unibus Drivers
2 M784 Unibus Receivers
1 M7843 DR-11
2 M7846 RX11 Unibus Interface
7 M7847 MS11 (One of these is missing the voltage regulator (TO-3 package))
4 M7850 Parity Module (2)
8 M7856 DL11-W,SLU/RTC OPTION
2 M7859 KY11-LB Programmer's Console
7 M7860 DR11-C = M786 + M105 + M7821
3 M7867 DVP 11-DA
1 M7895YA 48 (5V Optical Isolated) Channel Input DSS11
3 M7940 Serial Line Unit
4 M7941 16-bit Parallel Line Unit (DRV11)
8 M7944 4K RAM
3 M7946 RXV11 LSI 11 Interface
1 M7949 LAV-11
1 M7950 DRV11-B
1 M7952 Programmable Realtime Clock
1 M7955 MSV11-C LSI MOS Memory (4x16xIntel2104)
1 M796 Unibus Master Control
1 M798 UNIBUS driver
1 M7992 TXM UNIBUS CONTROL & CRC
1 M8012 Boot-Terminator and Diagnostic ROM Module
1 M8013 RLV-11 Disk Control
1 M8014 RLV-11 Bus Control
1 M8029 RXV21,Q-BUS RX02 INTERFACE,DO
2 M8043 DLV11J 4 Serial Line Unit
2 M8044DB 32k x 16 MOS Memory (M8045 PCB)
1 M8044DF 32k x 16 MOS Memory (M8045 PCB)
2 M8047 MXV 11 A
2 M8186 KDF11-AC DUAL HEIGHT CPU,Q-BU
3 M8192 DUAL HEIGHT CPU BRD (KDJ11-A)
1 M8256 RX211, UNIBUS RX02 INTERFACE
1 M8264 NO SACK Timeout Module
1 M8265 KD11E-A PDP-11/34A Data Path
1 M8266 KD11E-A PDP-11/34A Control
1 M827 KE11-A Clock & States
1 M8403 4 SLU
1 M8916 Logic and Write Board
1 M8931 Slave Clock and Motion Delay
1 M9001YC Gen Purpose Card
4 M9016 RK06 Cabling Bd.
1 M9301YA Bootstrap
2 M9301YF PDP11 Unibus Terminator/Bootstrap
1 M9302 11/04 UNIBUS TERMINATOR,FAR E
--
Robert Krten, PARSE Software Devices, http://www.parse.com/resume.html
Hello all,
I have an IBM 5150 PC in need of a new keyboard .... Willing to pay some $$,
but hopefully not too much! :-)
If anyone has one, can you please let me know how much you want for it?
Also, please quote shipping to 01473.
Thanks!
Rich B.
