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

[rocket.scientist]

I have a few HP-41s, both fullnut and halfnut. All being HP, I have an affinity for both versions. It bothers me that I know so little about the design of the Halfnuts. I guess I have always been motivated more by things I know I do not know, than things I do. It is an unquenchable thirst for knowledge.

I definitely agree the schematics have been missing from the community for a long time. Looking at the metadata and fingerprints in the available PDFs, it is clear they were scanned from paper almost a decade ago, if not longer. Looking closely at the PDFs, there are indications the schematics were present in the paper version. Para7-41 states "The schematics for the Halfnut HP-41C/CV/CX are shown in figures 7-9, 7-10 and 7-11, respectively. They are provided for information only since the alarm is the only replaceable discrete component." Further, for PDF versions with the poorly scanned final page, it is clear it is the HP-41 Exploded View, and you can just make out it is on page 7-21. That leaves pages 7-13 thru 7-20 missing.

I know I am not as knowledgeable as most of my fellows here, so it surprises me a bit that I am one of a very few to note this discrepancy. As you point out, it may not matter to most. These Halfnuts are not designed to be field serviceable, and only minimally so at the factory. I see it as a gap in my knowledge, and a potential impediment to my ability as a hobbyist seeking to preserving these devices. I prefer to believe the schematics are present in the paper version of the document, and that someone in this forum has a copy. One day they will surface and we can add them to this wonderful collection.

Thanks to everyone for the ideas and suggestions. I'll leave this thread alone unless something new turns up.

Kindest Regards,

-Pat (KG5YPQ)