IBM 1130 Restoration at TNMOC in 2011

The system at TNMOC is an IBM 1130 model 2B with 8KW 3.6us core store, internal IBM 2310 512KW removable disk drive, IBM 1132 printer and an IBM 1442 model 6 card reader/punch. We also have an IBM 29 Card Punch which is part of the TNMOC collection before the 1130 arrived. The 1130 system is on loan from The Museums of Liverpool and arrived at TNMOC on 22nd May 2009.

Below you can read the logs from the restoration project team of Stewart Baker and Peter Vaughan.

Start of Stewart Baker's involvement in the IBM 1130 restoration.

07 April 2011 Update from Stewart Baker

Equipment moved to interim positions for display/restoration.
First level external cleaning of the equipment carried out.
The top cover of the LPT needed Meths to get out the ingrained carbon. The majority of panels should benefit from further cleaning using a variety of methods. The most obvious blemishes are the rusty scratches on the grey panels to the rear of the 1130 console. These will require attention.
All covers removed from the 1130 to view the internals. There is little sign of rust, and no obvious damage of any parts.
!!! There is a potential hazard of getting ribbon cables trapped whenever the processor rack is swung in/out and great care must be taken to prevent any cable damage !!!
My recommendation is that the CPU section should be accessed as little as possible.
The top cover was removed from the top of the disk drive to examine the condition of the heads, there having been a report that they were stuck to the removable drive platter. It was found (to much relief) that the heads were in the home position, and that no damage to the disk oxide surface was apparent. Further the spindle bearings, belts and motor show no signs of mechanical binding. The disk has been left in the mechanically locked position as a precaution against any potential damage.
The unit shows a considerable British content with labels bearing company names with "Ltd". In fact there is one from PYE. Most of these are attached to cableforms. Various paper labels that were in danger of becoming detached from the metalwork were temporarily secured at the top and bottom with tape.
To make future access to all areas of the machine easier, all hinges and locking pins were cleaned of corrosion and lightly lubricated with WD40.

09 April 2011 Update from Stewart Baker

Meeting with Peter Vaughan to discuss all aspects of 1130 restoration.
On-site spares identified, together with those Peter is protecting at home.
Archived punch cards need to be re-labelled before the pencil markings fade completely.
Documation card reader found. Needs to be moved to the same area in D-block as the spare Selectric printer.
Need to find power distribution diagrams of the system before proceeding with PSU evaluation.

15 April 2011 Update from Stewart Baker

External cleaning of 1131 completed. Most panels are OK, however the blue panel in front of the disk drive has rust under the paint. This is worst along the bottom edge of the panel. The punched card has been removed from the locking mechanism of the desk. This has now allowed the desk to fit without warping. The locking mechanism has been lubricated and can be operated using a screwdriver blade through the slot in a panel below the keyboard.
An IBM 1130 Restoration Proposal document is in progress detailing the short, medium and long term objectives / aims / goals.

20 April 2011 Update from Stewart Baker

Midpack Regulators MPR1,2 & 3 area cleaned and photographed.
Tuned 115v/230v transformer cleaned and photographed.
Front of Bulk Power Supplies (PSDC) cleaned and photographed.
Power Supply Blower (YP111) removed and cleaned. Fan in YP111 is 230v 50Hz.
Fan run for 4 hours without problem.
Filter under YP111 missing. Spare in Archive has a deteriorated filter medium - to be replaced.
Fuses in Power Sequence Box removed and checked for continuity.
Cream disk surround removed and cleaned. One of the grey plastic supports is missing, causing the switch panel to float.

13 May 2011 Update from Stewart Baker

All 1442 covers removed and cleaned.
Most panels are in good condition; however there is bad scratch damage to upper rear panel. Dust brushed and vacuumed out.
Lamp and switch covers cleaned on 1131, 1132 and 1442.
1131 keyboard cover removed and the area cleaned. There is some surface rust present.
Filter under YP111 refitted with new filter medium.
Emergency Stop switch reset and tested.

27 April 2011 Update from Stewart Baker

Tried to establish contact with primary 1130 user group 1130.org, but 3 emails failed to elicit any response.
Spare Selectric Console Printer retrieved from D-Block for evaluation and consideration as replacement for existing printer. Unfortunately this printer although in good condition having been refurbished in 1985 is not immediately suitable. a) Because it only supports pin feed paper b) Because it is much newer (model 55).
The unit was photographed and returned to D-Block. Existing console printer exterior cleaned.
+3V PSU removed from 1131 and cleaned. Although no circuit diagrams are presently available the circuit seems quite simple. The unit is supplied with a smoothed DC from another PSU and only provides regulation and overvoltage protection. Will be bench tested with external DC PSU and load.
Top covers (grey) removed from 1131 for Electrolytic treatment of rust. Halfords grey primer found to be a close colour match to existing paint.

03 June 2011 Update from Stewart Baker

Electrolytic treatment of rust completed on Top covers (grey). Comments about painting noted. Exposed areas on these panels treated with Carnauba wax instead. Exterior cleaning of 1131 now complete.
In order to better understand the Midpack Regulators functions, reverse engineering to CAD of the +3V unit has been carried out.
This shows that in addition to the main DC supply into the regulator, there is another DC supply into the unit for the voltage regulator card. Like the main DC supply voltage it's value at this time is unknown.
The series regulator transistors are Motorola 108's which are germanium technology, and look like they were specifically made for IBM. They are also used in the LPT and are rare items. We appear to have no spares.
It is intended to finish the documenting of the +3V regulator before moving onto the -3V and +6V units.
The -3V is identical to the +3V, however the +6V has some additional circuitry.
These units will be cleaned and examined, however without detailed information being available (at present) apart from testing the Overvoltage Crowbar protection PCB and looking for obvious faults, no powered testing outside the mainframe is practical.
Consideration has been given to removing and bench testing PS4 (+12v) and PS5 (+48v) located below the disk drive. It is my opinion that, because of their positioning the amount of upheaval and possible damage, that these supplies should be carefully tested in-situ. The 1131 system would appear to be well thought out in the provisioning of circuit breakers and fuses for the isolation and protection from fault conditions.
At present we have no schematic diagrams for any of the IBM 1130 suite, however there is a light at the end of the tunnel.
I have been successful in finally making contact with those running IBM1130.org, and we are now in dialogue mode. In addition to publishing our details on the 1130 web site, they are looking to scan and provide us with the schematic documents we need.
However, before power is applied to any part of the system I need to review the Terms and Conditions of the Loan Agreement signed with Liverpool Museum to ensure that we are complying with their restoration wishes.

20 June 2011 Update from Stewart Baker

Midpack Regulators -3v and +6v removed, cleaned and replaced in mainframe.
As the +6v regulator card is easily removed, CAD documentation has been left till later. The overvoltage crowbar PCB's need accurate checking of their trigger points.
All power supply fuses have been checked for continuity. Sticking fuse holders lubricated and cleaned.
The security of all accessible terminal block screws has been checked.
The internal cleaning of the 1131 is complete.
We are now subscribed to the IBM1130.org mailing list.
The "1130s Today" page on their web site contains details of our 1130 restoration, and links to TNMoC.

23 June 2011 Update from Stewart Baker

First sortie conducted on 1132 line printer. Tractor assembly de-rusted using electrolytic treatment. Initial stage of rust treatment to metal framework carried out. Equipment panels cleaned.

25 June 2011 Update from Stewart Baker

Disk cartridge removed from 2310 drive. Dust brushed and vacuumed out of drive.
R/W heads inspected using a mirror and light, no damage or oxide build up present.
R/W heads cleaned with cotton buds and IPA, no oxide residue found on cotton buds.
R/W head suspension springing examined, no defects found.
Surface of the 2315 disk cartridge examined. No evidence of damage found, however its surface is very dirty and needs cleaning with lint free cloths and IPA before any attempt is made to test the disk system.

01 July 2011 Update from Stewart Baker

Midpack PSU overvoltage crowbar triggers measured and labeled. +3V (4.07V), -3V (4.17V), +6V (7.15V)

05 July 2011 Update from Peter Vaughan

Bulk +12/+48v PSU removed after labelling all connectors. Visual inspection shows evidence of overheating on resistors underneath plastic cover. PSU contains many high capacity capacitors which need to be reconditioned prior to initial testing of PSU.
We are close to wanting to power up the machine once all PSUs have been checked. A plan of action and risk assessment is being done to reduce the chances of damage to the machine should a PSU fail.

05 August 2011 Update from Stewart Baker

1132 line printer.
Continued rust treatment on metal framework and front doors - On-going.

01 September 2011 Update from Stewart Baker

1132 line printer.
Continued rust treatment on metal framework, side panels and rear doors.
Side panels rehung. On-going.
Repositioned IBM suite in display area.

14 September 2011 Update from Stewart Baker

Examination and cleaning of Bulk PSU.
Distortion/discolouring of perspex shield over capacitors at the PSU rear investigated. This has been caused by heating from bleeder resistors.
Shield heated and flattened. In an attempt to prevent further damage the shield has been positioned further from the resistors using washers as spacers.
Bulk PSU capacitors C1 to C9 checked for ESR, leakage and then reformed. All capacitors are in good physical and electrical condition.

19 September 2011 Update from Stewart Baker

Bulk PSU refitted in 1131 chassis.

21 September 2011 Update from Stewart Baker

1131 Power up task commenced
Unit moved into clear area, all covers removed and CPU & SDA racks opened.
All PSU fuses removed and stored. All circuit breakers and power switches OFF.
Unit powered from Variac with an AVO in circuit to measure current.
Negligible leakage current measured at 220V AC applied.
Circuit breaker CB1 closed and 20mA measured when relay R3 pulls in (24v AC T1).
Fitted fuse F5 and closed Power and CE switch. Contactor K1 pulls in at approx 150V AC input.
All fans running, but system powers itself down after 5 seconds due to a missing MidPack PSU rail or rails.
Fitted fuse F1 and closed breakers on MidPack PSUs to see if that was the problem.
Found that MidPack Bulk PSU needs to be on to supply unregulated inputs to MidPack regulators.
Fitted fuse F2 and gradually powered system to 220V AC input. No new issues, but the system still powers down after 5 secs.
Measured continuities between MidPack Bulk PSU and MidPack regulator inputs all OK.
Measured input voltages into MidPack regulators from Bulk PSU, all OK (approx 6.6V and 11.5V).
Found +3V MidPack rail missing, all others OK. Swapping regulator PCB with -3V one did not cure the problem.
+3V MidPack PSU removed for bench diagnosis and rectification.
Olly's help was much appreciated in power up activity.
After +3V PSU is fixed only the lamp supply and convenience outlets need checking as part of the 1131 power up actions.
I am on holiday for 2 weeks, and will pick up remaining items on my return.

21 September 2011 Update from Peter Vaughan

The spare PSU I have is labelled 3V/20A with a +3 square stamp so this looks like a +3V PSU that could be tried in the system (after being checked) or used to diagnose the faulty +3 PSU. I can arrange for it to be delivered to the museum for your return.

22 September 2011 Update from Stewart Baker

Thanks Peter, that would be very useful.

23 September 2011 Update from Stewart Baker

Mulling over the problem, looked at photo of MidPack regulators taken before their removal and spotted the link (or absence of !).
Link fitted to +3V terminal block.
System now powers up and stays up. !!! Whoopee !!!
Measured supply rails at test points on CPU chassis. All well within tolerance.
- -3V (-3.08V), +3V (+3.08), +6V (+6.1V), +12V (12.7V), +48V (+49.5V).
Display lamps tested. Only 3 bad.
CPU Runs, Single Instruction and Single Steps (something left in core memory).
Mains input kept around 210V AC to reduce stress, and system left to soak for 2 hours.
"Hot smell" noticed. Eventually traced to stalled motor in Console Printer. The motor is required to run all the time the 1130 is powered on.
Investigated Console Printer. Motor is working, but stalls trying to drive very stiff mechanics.
So, quite a lot of success today, and I will investigate the Console Printer after my holidays.
In the mean time the 1131 is rather delicate, and should not be powered up.

12 October 2011 Update from Stewart Baker

Console Printer mechanics very stiff. Loosened/removed stale grease with copious amounts of WD40.
Motor now drives the mechanics, with no more "Hot smell", however it chatters like a Teletype all the time.
Need to investigate whether it still does this when the interface to the 1131 is disconnected.
There is a power switch underneath the printer to permit mains isolation without the need to power down the 1131.

16 October 2011 Update from Stewart Baker

Web research shows that Selectric Typewriters/Printers that had been idle for a long time were immersed in a solvent bath before being re-lubricated.
Although a maintenance manual for a Selectric Keyboardless Printer has been located, specialist assistance may be needed to restore the unit to a fully working condition.

19 October 2011 Update from Stewart Baker

Blown bulbs and ones with high resistance filaments changed in Status Panel. All bulbs now working.
Initial investigation of IBM 29 Card Punch.
It appears to be in good condition.
Unit cleaned internally, screw and paddle boards connections checked.
Operating arm and roller missing from card stack microswitch. Should be easy to replace.

25 October 2011 Update from Stewart Baker

IBM 29 Card Punch cleaned externally.
Blown bulbs in 1131 desk panel replaced.
IBM 2315 disk cartridge examined and cleaned. The surface shows signs of contamination, but the biggest issue is a scratch on the lower surface in line with the index mark. This not bad enough to instigate a head crash, however the disk should only be used for testing, and not data storage.
It is believed that CHM in Mountain View have some, so maybe a deal can be struck ? Christian from Stuttgart uni may be able to supply some as detailed in the 1130 Google group thread: https://groups.google.com/d/topic/ibm1130/jfpovyZlh7E/discussion Source for disk packs ( Peter Vaughan, 25 October 2011)
Attempt to run up disk in 1131 was initially unsuccessful as the drive would not come up to speed (1500rpm). This prevented the heads from being loaded on to the disk surface. It was thought that lack of lubrication might be the cause, and so after consulting the FEMM for the drive, specific items were lubricated. These included the spindle drive motor which has a channel in its top casting for such a purpose.
After the motor was lubricated the heads loaded OK and the File Ready light came on. No head crashing or other undesirable effects occurred.
The manual says that there is a 90 sec delay before the heads are loaded, but it was observed to be almost 2 mins.
The heads were examined and no signs of oxide deposit was found.
Exercising the drive was left to a later date as it involves disconnecting data cables so that the internal CE switches become active.

26 October 2011 Update from Stewart Baker

IBM 29 Card Punch cleaned internally.
Mechanics lubricated with 3 - IN - ONE oil as per schedule in the FEMM, but re-greasing felt to be unnecessary.
Main motor Drive Belt removed as it has two splits in it, one almost through the belt to the canvas. Replacement belt sought.

02 November 2011 Update from Stewart Baker

New Drive Belt fitted to IBM 29. New spare and original left inside machine.
Machine powered up. Basically working, but needs some maintenance.
Some keyboard keys stuck down. Result of "must-touch-it-itis" ?
Investigation of console printer with Olly.
Some progress, however the printer still sits there doing CR/LF's.

12 November 2011 Update from Stewart Baker

IBM 29 Card Punch
Cleaned card paths and removed metal burrs to enable consistent card feeding.
Cards being fed, but no punch operation.
Two micro switches in card path gummed up with grease and dirt - cleaned.
Unit now punches cards correctly, but card feed from middle to left station unsatisfactory.
Further mechanical attention needed.

16 November 2011 Update from Stewart Baker

Card path adjustments made according to FEMM using Gram and Feeler gauges.
All card punch functions including DUP working OK.
Card punch now available for general use (See power up/down instructions).

24 November 2011 Update from Stewart Baker

New roller micro switch fitted to IBM 29 card stack monitor.
Interface to 1131 console printer disconnected, however it still performs uncommanded CR/LF's.
Note:- To gain access to console printer ribbon or golfball removing the transparent plastic cover
is unnecessary, as there is a black metal tab that raises the entire top cover of the printer.

30 November 2011 Update from Stewart Baker

IBM 1442 Card Reader/Punch
Internal clean carried out.
Fuses and panel bulbs checked.
Tightness of all screws on connector panels checked.
Close visual examination of the PSU carried out.
Contacts cleaned on switches and relays in the PSU.
C2 and C3 (17,000uF 14V) capacitors reformed OK.
C4 (4,000uF 15V) proved to be open circuit, replacement/substitute needed.
C4 capacitor dimensions 50mm dia, 90mm long.

06 December 2011 Update from Stewart Baker

New capacitor (4,700uF 63V) piggy backed across C4.
IBM 1442 Card Reader/Punch connected to IBM 1130 with PSU cable and system powered on.
No smoke or other form of distress observed.
Internally generated +12V and 4.3V AC rails checked OK.
Data cable connected to IBM 1130 and system powered on.
Again no smoke or other form of distress observed in either the 1142 or 1131.
Power On, Check and Trans (on status panel) lamps lit.
The Check/Trans (Stacker Jam) error is not being caused by a card jam or defective uSwitch.
Need to investigate signal path as it may being generated in the 1131, however without circuit diagrams this will be difficult.

07 December 2011 Update from Stewart Baker

Peter Vaughan has drawn my attention to a PDF on the Stuttgart University ftp site containing IBM 1442 logic and circuit diagrams.
Thanks Peter... Electronic fault finding on the unit can now proceed.

08 December 2011 Update from Stewart Baker

Worked with Peter Vaughan to locate cause of IBM 1442 reported errors. Discovered Light Source Lamp blown.
Lamp is a 8V 50W special made by Osram, however they are still available. One listed on ebay.
Changed lamp for a spare, which although not the same shape has the same electrical characteristics.
Unit now giving READ STA and PUNCH STA errors. The READ STA error is due to CH12 of Read Head not working.
This maybe due to either dirt or more likely insufficient light through that Fibre Optic channel.
Light Source Lamp adjustment needs checking, together with a clean on the Read Head assembly.
The card path has some corrosion of the aluminium, particularly at the Stacker Cornering Station. This should polish off.

13 December 2011 Update from Stewart Baker

Rough setting of Light Source voltage made (needs fine adjustment as per FEMM).
Unit now going Ready with no Status errors.
Card path corrosion cleaned off with Brasso. Some pitting evident in aluminium, but should not effect operation of unit.
Freed small seized bearing after punch station, and refitted loose metal guide piece.
Unit now feeds cards, although it occasionally jams by selecting the wrong output hopper path (adjustment ?)
All local functions on IBM 1142 work, together with Program Load and Reset from the IBM 1130.
Close to trying to boot the IBM 1130 from punched cards...

17 December 2011 Update from Stewart Baker

IBM 29 has an issue duplicating single cards. There is not enough skew adjustment at the read station due to the wear
in a small bearing. Feeding cards to be duplicated through the normal card path works OK.
New Light Source bulb of the original type fitted, so no optical alignment should be necessary.
Hopper path solenoid back stop adjusted. Jam switch tape clearances reset.
Mechanical adjustments made as per the IBM 1442 FEMM to items in the card path of the Stacker Cornering Station.
A couple of these adjustments were a long way out. No repeat of card jams so far...
IBM 1131 CPU operation is not correct. Discussion with Peter Vaughan on way to proceed with the fault finding.

22 December 2011 Update from Stewart Baker

Fault finding of IBM 1131 CPU started. System oscillator waveform examined and frequency read as 2.25MHz.
Discovered that CE panel switches work in opposite sense to Test Lamp switch.
This was causing CPU to permanently execute a core memory test !
No indication of correct position in any IBM manual or panel legend...
Now able to load and read from core memory. Simple routines used to load pattern into memory.
FEMM 1.7.5 Core Store Console Isolation test run without any core parity errors.
Next steps - IPL and ripple card read from IBM 1442 into memory.

28 December 2011 Update from Peter Vaughan

An initial audit of the punch cards that arrived with the 1130 has been done. We appear to have a master and working copy of a number of diagnostics card sets plus a number in a different draw labelled as old versions. Details of these still need to be documented.
We also have one copy only of a number of ripple card sets for testing alignment of the 1442.
Many of these diagnostics sets are too big to copy using the 029 so some other method is needed to make working copies for us to use. Where possible we only want to work on our own copies of the cards.
Using a working copy of the 7 card set of one card diagnostics, a copy of each card was attempted using the IBM 029. After several attempts and a few crunched cards copies were made of all but card 05, which keeps causing a card feed issues when a duplicate is made. During the duplication punching sometimes started at column 2 rather than 1. More work may be needed to improve the reliability of the 029 and to discover why it does not like card 05.
Any attempt to load the cards into the 1131 from the 1442 results in the 1442 going into an error state so the only option is to enter the programs by hand.

29 December 2011 Update from Peter Vaughan

Work continues with 1131 processor diagnostics.
A set of 7 one card diagnostic programs (ocdp) exists to test some of the basic instructions in the processor. As these cannot be loaded from the 1442, we are entering the instructions from assembly listings straight into core store using the console switches. So far ocdp01 -> 04 have been entered and run successfully which has tested a number of load/store/add/xor/wait and branch instructions. ocdp05 has been loaded but currently fails so further investigations are needed to discover why.
There appears to be a bit fault at core memory location 0x50 which is reproducible when reading the store in display mode, however it does not appear to fail the simple CE engineering core store write and read test so it is not clear if this is a fault or not.