Notebook kept by Ernest Lenaerts during his work on the LEO computer, dated 6th July to 9th October 1950.

View the transcription for this notebook (opens as a separate document).

Includes entries:
NB03-001: 6 Jul 1950
NB03-002: 7 Jul 1950
NB03-006: 11-12 Jul 1950
NB03-007: 12-13 Jul 1950
NB03-011: 17 Jul 1950 
NB03-012: Notes on Possible Reciprocation Sequence. 
NB03-013: 19 Jul 1950
NB03-015: 20-21 Jul 1950
NB03-016: Diagrams and measurements for design of bicycle trailer - non-LEO related.
NB03-017: 24 Jul 1950
NB03-018: 25 Jul 1950
NB03-019: 25 Jul 1950 (cont.) Includes to-do list for cycling/camping trip - non-LEO related.
NB03-020: 26 Jul 1950 
NB03-021: Suggested Feature Programme [different handwriting, poss written on a train or similar? On/after his holiday.]
NB03-022: Fri Aug 11th. Priority of jobs [different handwriting, poss written on a train or similar? On/after his holiday.]
NB03-023: Mon 11th Aug 1950. Work commenced on Rack tests of the Coordinator
NB03-024: 16 Aug 1950
NB03-026: 17 Aug 1950 
NB03-027: 17-18 Aug 1950 
NB03-028: 21-22 Aug 1950 
NB03-029: 22-23 Aug 1950
NB03-030: 24 Aug 1950. Parts and processes still to be tested
NB03-031: 25 Aug 1950
NB03-032: 28 Aug 1950
NB03-035: 29 Aug 1950
NB03-036: 30 Aug 1950
NB03-038: 31 Aug 1950 
NB03-042: 1 Sep 1950  
NB03-046: 4 Sep 1950 
NB03-047: 6 Sep 1950 
NB03-048: 7 Sep 1950 
NB03-049: 8 Sep 1950 
NB03-052: 11 Sep 1950. Moving Coil pickup diagrams. Review of Progress.
NB03-053: 11 Sep 1950 (cont.) Work on Machine
NB03-056: 11 Sep 1950 (cont.) 'TRT & JMMP returned from holiday today. I set LEO up in lights on the raster scope for their benefit and they were duly impressed'.
NB03-057: 11 Sep 1950 (cont.) Experiment to Try Out.
NB03-058: 12 Sep 1950
NB03-062: 13 Sep 1950
NB03-064: 14 Sep 1950
NB03-065: 15 Sep 1950. Refusal of SCT to accept Is
NB03-066: 15 Sep 1950 (cont.) * [EL asterisked]
NB03-067: 18 Sep 1950 
NB03-070: 19 Sep 1950 
NB03-071: 20 Sep 1950 
NB03-075: 21 Sep 1950
NB03-077: 22 Sep 1950
NB03-079: 25 Sep 1950
NB03-080: 26-27 Sep 1950
NB03-082: 28 Sep 1950 
NB03-084: 29 Sep 1950
NB03-086: 2 Oct 1950
NB03-088: 6 Oct 1950. [dated 6.9.50 instead of October in error]
NB03-093: 9 Oct 1950
NB03-094: [EL here seems to be working out patterns of lights to display a message on a machine - 'No Errors/Mistakes']

The Lenaerts notebooks are being digitised and transcribed as part of the National Lottery Heritage Funded LEO project at The Centre for Computing History.  We are indebted to our team of volunteers for scanning and transcribing the notebooks. If you would like to get involved with our work on these fascinating documents, please get in touch!

Provenance :
The notebooks are being digitised while on loan to The Centre for Computing History from the LEO Computers Society, with the kind permission of the Lenaerts family.