Click Here to visit our Sponsor
The Latest News ! The History of Computing The Magazine Have Fun there ! Buy books and goodies
  Click here to loginLogin Click here to print the pagePrinter ViewClick here to send a link to this page to a friendTell a FriendTell us what you think about this pageRate this PageMistake ? You have mr info ? Click here !Add Info     Search     Click here use the advanced search engine
Browse console museumBrowse pong museum


Ready prompt T-shirts!

see details
C64 maze generator T-shirts!

see details
Spiral program T-shirts!

see details
Pixel Deer T-shirts!

see details
BASIC code T-shirts!

see details
Pak Pak Monster T-shirts!

see details
Pixel adventure T-shirts!

see details
Vector ship T-shirts!

see details
Breakout T-shirts!

see details
Shooting gallery T-shirts!

see details

I > IBM  > AN/FSQ-7   


The AN/FSQ-7 was by far the largest computer ever built, and is expected to hold that record. It consisted of two complete Whirlwind II computers installed in a 4-story building (See the impressive diagram in the 'More Pictures' section).

Each AN/FSQ supported more than 100 users. IBM had about 60 employees at each site for round-the-clock maintenance.
Keeping one unit operating and one on hot standby (to allow for switchover when vacuum tubes failed) resulted in better than 99% uptime. The roles of the two units were reversed at regular intervals, allowing diagnostics and maintenance to be carried out on the standby unit.

There were usually several hundred tube failures each day, replaced by workers racing up and down the tube racks with shopping carts full of replacements. Automated tests run by the computer itself would cycle the voltage to the tube racks down and back up to induce marginal tubes to fail early, so that the computer would normally run correctly for the rest of the day. Without this process, the MTBF would have been a few minutes.

By the time SAGE was deployed (22 or 23 stations in the period 1959-1963; sources disagree) it was nearly obsolete, since it was designed to detect bombers, not the new ICBMs. Nevertheless it was operational until 1979, when the ROCC (Regional Operations Control Centers) system took over, using much higher-speed computers. One SAGE station continued operating until 1983. This last unit was donated to the Boston Computing Museum, since relocated to Moffett Field in Mountain View, California. The museum also has a tube panel from the Whirlwind I. Whirlwind II consoles turned up in the TV series Battlestar Galactica.
In spite of its limited military value, the SAGE system served as an excellent prototype for an air-traffic control system. The FAA operated its own AN/FSQ-7 systems for many years after SAGE was shut down. IBM's experience with these systems had a great deal to do with its later success in computer systems, and its dominance of the market for large computers. The IBM 7090 was essentially a solid-state version of the AN/FSQ-7/8. (The 7090 has its own rich history, including hosting the first-ever multiuser APL system.)

• First CRT-based real-time user interface,
• First use of light gun to pick an item on the screen,
• First wide-area modem communications (1300 bps),
• First hot standby system for maximum uptime,
• First ground control of interceptor aircraft,
• The first in line microfilm fast processed 35 mm projection displays, preceding printer/plotters. A screen capture could be displayed within 30 seconds, • First two-pass assembler, permitting symbolic addresses.

Thanks to Edward Cherlin, Simputer Evangelist, for all this information.

The photo (from Mitre) shows the rear panel wiring of FSQ-7 arithmetic element frame.

We need more info about this computer ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.



Obviously it was Keesler AFB, Biloxi, Mississippi

Tuesday 8th November 2016
Herb Pfeifer

I attended Q-7 training at Biloxi AFB in 1967-1968 but was never assigned to a Q-7 site. Instead I was assigned to the NORAD cave and later to the BUIC site at Havre AFS.

An interesting observation about the Q-7 was its extremely high reliability due to marginal testing of the backup system when the tubes were subjected to over and under voltage stresses. Vacuum tubes that would have failed during normal operation were "Pre-failed" on the backup system rather than being allowed to fail during critical online operation.

As you might imaging, the building housing the Q-7 required only air conditioning, but not heat as this was provided by over 100,000 vacuum tubes.

Tuesday 8th November 2016
Herb Pfeifer

I worked on the Q7 from 1974-76...I/O and Displays, at Duluth, MN.

Was a lot of fun to work on! Had big and little memory, drums, reel-to-reel tape, card reader, printer (used relays...lots of them). Would boot up using a plug board(if I recall the name). The display console had a 10,000 volt power supply that had to be checked during maintenance. You have to turn off the power, attach your probes and then turn power on. If you attached the probes before powering off, the jolt would knock you back on your butt...or worse.

Toughest problem I worked on was an intermittent failure that we finally found by turning off the lights where the frames with pus and looked for bad tubes. We found the blue tube.

The other cool thing was that there was a speaker that would emit these squeak-like sounds while the main program (active mode) was running. It was the same sound pattern over and over so you could tell by listening if things were running okay. You also would know when things were going down. Then the commander would call down from the fourth floor over the loud speaker. Hee, hee.

Fun times.

Thursday 18th August 2016
Jeff Davis (USA)


TYPE  Professional Computer
YEAR  1958
KEYBOARD  IBM consoles
CPU  55,000 vacuum tubes in each unit
SPEED  75 KIPS (KiloInstructions Per Second)
RAM  Core 8892-word
ROM  Unknown
GRAPHIC MODES  256 x 256
COLORS  Monochrome
SOUND  Speaker (see the ''Read more'' page)
SIZE / WEIGHT  2000 square meters / 275 tons
I/O PORTS  Tape, punched cards, modem
OS  None
PRICE  $238 million, printer around $200,000 to $250,000

retro computing t-shirts and goodies
3D Cubes
BASIC code
C64 maze generator
Pak Pak Monster
Pixel adventure
Pixel Deer
Ready prompt
Shooting gallery
Spiral program
Vector ship

Related Ebay auctions in real time - click to buy yours

Click here to go to the top of the page   
Contact us | members | about | donate old-systems | FAQ
OLD-COMPUTERS.COM is hosted by - NYI (New York Internet) -