Still looking for HP-41C/CV/CX HalfNut Schematics

[rocket.scientist]

Here is where I am in this search. I have reached out to a couple of the principals identified in the "HP 41C data storage integrated circuit swapping" thread above. There have been no responses yet, but I remain hopeful. On the knowledge already in the archives, I have identified 3 cases that appear to describe the 00041-90472 / 00041-90542 documents already out there. Note in all 3 cases, the first page of the PDF is full color with a blue cover sheet marked by HP appropriately. This is based on finding this document at 6 different sites, some common, some not so common.

Case 1: The base document 00041-90472 does not contain Appendix VII "HP-41 Halfnut Construction", which is where the halfnut schematics are reputed to appear.

Case 2: The base document does contain Appendix VII, and the following pages are a series of alternating good pages and blurry "scanned through the page" reversed pages. The TOC for Appendix VII cites schematics for the various halfnuts are in Figures 7-9, 10 and 11 (pages 7-15 thru 19). This version of the scan ends at page 7-12, and usually has a reversed blurry "through the page" scan of Figure 7-12 (page 7-21), the HP-41 Exploded view. The schematics are missing. This version was produced with sspdflib 1.0 (ScanSoft).

Case 3: The base document does contain Appendix VII, and the following pages are all clearly scanned and consecutive. Again the TOC for Appendix VII cites schematics for the various halfnuts are in Figures 7-9, 10 and 11 (pages 7-15 thru 19). This version of the scan ends at page 7-12. This is the end of the scanned document and the schematics are missing. This version was scanned in 2012 and produced with AFPL Ghostscript 8.11.

Every time I find this document one of the three conditions above apply. So far my conclusion is that the halfnut schematics are missing, perhaps deliberately, from accessible HP-41 archives. It may also be that the schematics were printed landscape, and the original scanners did not go back and include them.

If someone has this document with a complete Appendix VII, or if you run across a complete scanned version somewhere online, please consider sharing it with the community.

Regards,

-Pat (KG5YPQ)