TX-2 Project

Re-creating the historically important TX-2 computer

Photographs

Lincoln Lab 2022-10-31 Release

I asked Lincoln Lab about release of photographs of the TX-2’s console. On 2022-10-31 they kindly provided a number of photographs of the computer in use and several parts of the console. Some of these photos are also included in the TX-2 Technical Manual, but they are generally low-resolution cropped images.

The general layout of the room is shown in Figure 5-1 on page 5-2 (physical page 127) of The TX-2 Users Handbook.

P91-113: 1961-03-28, Toggle switch storage panel

P91-113: 03/28/1961, The toggle switch storage panel and system
registers are on the left of this panel and I/O status registers are
on the right.

The toggle switches are at the bottom of the panel. At the top is a calendar, and below that are indicators showing the contents of the system registers (K, P, N, FA, F, N, X, Q, M, D, A, B, C, though not all of these are programmer-accessible).

On the right of this panel are sequence number status indicators, though the sequence number assignments are closer to those described in the TX-2 User’s Handbook.

P91-185: 1962-06-20, Unidentified woman working at TX-2 Control Desk Using the Lincoln Writer

P91-185: 06/20/1962, Unidentified woman working at TX-2 Control Desk Using the Lincoln Writer

P91-211: 1962-08-12, Ivan Sutherland using Sketchpad graphics program at the TX-2 Computer

P91-211: 12/08/1962, Ivan Sutherland using Sketchpad graphics program at the TX-2 Computer.

Sutherland is using the Lite Pen in combination with a push-button unit, perhaps the same unit shown at foot level on the left of photograph P91-206.

P91-206: 1962-10-29, Two unidentified women working at the TX-2 Control Desk, console

P91-206: 10/29/1962,  Two unidentified women working at the TX-2 Control Desk, console.

Here the CRT is visible in Frame 1, not having yet been removed. The woman on the right is operating the Lincoln Writer. At the extreme right of the photograph is the photoelectric tape reader.

P91-214: 1963-02-28, Console Indicator Panel

P91-214: 02/28/1963, This photo appears in: "TX-2 Users Handbook," Lincoln Manual No. 45, July, 1961, p. 5-5, Figure 5-4.: Console Indicator Panel.

P91-215: 1963-02-28, Alarm and Sync Systems

P91-215: 02/28/1963, A Cropped version of this photo, showing the
right side of the photo, appears is in: "TX-2 Users Handbook," Lincoln
Manual No. 45, July, 1961, p. 5-11, Figure 5-5.: Alarms, conditions
and Action Pushbuttons. [same photo also appears on pp. 5-16 and
5-18]; A Cropped version of this photo, showing the left side of the
photo, appears in: "TX-2 Users Handbook," Lincoln Manual No. 45, July,
1961, p. 5-21, Figure 5-9.: TX-2 Sync
System.

P91-217: 1963-02-28 Maintenance Console

P91-217: 02/28/1963, This photo appears in: "TX-2 Users Handbook," Lincoln Manual No. 45, July, 1961, p. 5-3, Figure 5-3.: Maintenance Console.

The Maintenance Console is used for marginal testing (varying the power supply voltage to identify components which are about to fail). It also contains the operating time counters.

P91-218: 1963-02-28 Power Panel

P91-218: 02/28/1963,  A Cropped version of this photo appears in: "TX-2 Users Handbook," Lincoln Manual No. 45, July, 1961, p. 5-3, Figure 5-2.: Power Panel (in the Power Room).

Below the main warning sign is a notice explaining how to shut the system down properly before turning off the power.

P91-219: 1963-02-28 IN-OUT Buffers and Special Indicators

P91-219: 02/28/1963, This photo appears in: "TX-2 Users Handbook," Lincoln Manual No. 45, July, 1961, p. 5-15, Figure 5-7.: IN-OUT Buffers and Special Indicators.

This photograph again shows the status indicators for each of the TX-2’s sequences.

P91-233: 1963-12-06, Timothy Johnson uses Sketchpad on the TX-2 computer

P91-233: 12/06/1963, Timothy Johnson uses Sketchpad on the TX-2 computer

The program being used is probably Sketchpad-III, according to Alan Kay. Sketchpad-III was the subject of Timothy Johnson’s 1963 thesis.

CP91-71: 1975-06-11, John Frankovich (L) and Omar Wheeler (R) working at the TX-2 Main Console (Frame 1)

The photograph shows John Frankovich (Left) and Omar Wheeler (Right)
working at the TX-2 Main Console.

Photograph CP91-71 (1975-06-11) shows John Frankovich (Left) and Omar Wheeler (Right) working at the TX-2 Main Console (Frame 1). The circuit breaker location and console indicator panels are behind Wheeler. These are shown in more detail below. The CRT is missing from Frame 1, presumably having been removed some time after Ivan Sutherland’s work on Sketchpad.

CP91-119: 1975-07-25, Circuit breaker location panel

CP91-119: 07/25/1975, Circuit breaker location panel

Photograph CP91-119, 1975-07-25, shows the panels on the far right of Frame 1.The circuit breaker location panel is at the bottom left of this photograph. On the right are the status indicators of the system sequences. Many of these are documented in the TX-2 User’s Handbook.

This photograph is over ten years more recent than the version of the TX-2 User’s Handbook that we have and so some sequences shown on this panel are different. These changes are described in Sequence Changes.

Original Captions

The captions originally supplied by Lincoln Lab for the photos in this release are here.