"Extra' plastic piece fell out of 41C — Where does it go?

Everything about 41C 41CV and 41CX Hardware

"Extra' plastic piece fell out of 41C — Where does it go?

Postby Jordan Orlando » Thu Apr 15, 2021 2:43 am

I opened up my "new" 41C (from eBay) to clean the contacts and see if there was anything I could tighten up inside — the calculator had been working perfectly (with three modules) but now the display wasn't working and it felt like something was loose.

When I took the battery compartment out and removed the four screws, and then separated the two halves of the calculator, a plastic strut dropped out (see photos below).

I can't figure out where this piece is supposed to fit!

It's the same width as the PCB at the bottom of the calculator, but it doesn't seem to belong at either the top or bottom edge of that (the top edge being the spot where the board "mates" with the edge of the battery compartment).

The machine fits back together perfectly without that piece, and powers up....my superficial cleaning of the flexible connector from the main board to the batteries and into the sockets for the modules seems to have worked.

I'm still having problems insofar as putting a module into slot "2" (top right, when viewing the calculator from "above") makes it stop working. Any advice as far as this goes, would be appreciated.

Thanks in advance for anyone's help and advice! I've only been a 41C owner for a couple of weeks but it's obvious that the community here and elsewhere is doing fascinating things with this wonderful old technology. (As I remarked elsewhere here, I've wanted one of these since my Dad brought home the brochures when I was in middle school.)

Jordan

Image
Image
Jordan Orlando
......
......
 
Posts: 28
Joined: Sun Apr 04, 2021 11:16 am

Re: "Extra' plastic piece fell out of 41C — Where does it go

Postby Jordan Orlando » Tue Apr 20, 2021 10:51 am

I've determined (from eBay parts options and other sources) that this part is a "display spacer." I still don't understand where it's supposed to go, inside the 41-C.

The calculator seems to work fine without it...mostly. (I've had some power-down problems that I've determined have to do with loose or dirty connections and worn-out — but still working — battery contacts.)

Can anyone point me in the right direction, in terms of understanding how to replace this part into the machine? Thank you.
Jordan Orlando
......
......
 
Posts: 28
Joined: Sun Apr 04, 2021 11:16 am

Re: "Extra' plastic piece fell out of 41C — Where does it go

Postby BillBee » Tue Apr 20, 2021 2:13 pm

Hi There,

Your one photo that shows the two black blobs is the area behind the display. it fits at the edge above it. Without opening one up I can't tell you the orientation but it will sit flush with no forcing when correct. I want to say its the two ridges up but again there are a limited amount of positions to try. :) Do put it back as it is meant to help keep dust out and once behind the display plastic dust is tough to get rid of.

Hope that helps.

1st Post!
-Bill
BillBee
...
...
 
Posts: 8
Joined: Tue Apr 20, 2021 2:06 pm

Re: "Extra' plastic piece fell out of 41C — Where does it go

Postby Jordan Orlando » Tue Apr 20, 2021 5:28 pm

BillBee wrote:Hi There,

Your one photo that shows the two black blobs is the area behind the display. it fits at the edge above it. Without opening one up I can't tell you the orientation but it will sit flush with no forcing when correct. I want to say its the two ridges up but again there are a limited amount of positions to try. :) Do put it back as it is meant to help keep dust out and once behind the display plastic dust is tough to get rid of.

Hope that helps.

1st Post!
-Bill


Thank you very much, Bill! I just put it back in.

I felt like a kid trying to solve a puzzle, looking for the proper spot for the thing. (I think the previous owner was also baffled and just dropped it into the enclosure — it fell right out the first time I opened the calculator up.)

Welcome to the forum! I'm a newcomer myself — just 17 posts. As I've explained elsewhere, I always wanted a 41C, since my Dad brought all the brochures home from work, when I was a kid. I got back into the HP concept after following a train of association through the history of IBM and 1960s computing — the most interesting period, when the industry was on the cusp of adopting ICs (the advantage being forced by the need for them in the Apollo Guidance Computer, arguably the greatest moment in the history of computing). I could go on. Anyway thanks again, Bill!
Jordan Orlando
......
......
 
Posts: 28
Joined: Sun Apr 04, 2021 11:16 am

Re: "Extra' plastic piece fell out of 41C — Where does it go

Postby BillBee » Wed Apr 21, 2021 11:38 am

Hi Jordan,

The reason I knew was that I had the same problem the first time I opened a 41 up and it fell out. :D

I do understand the HP desire. I went through college with a 15c and I love that series. Then some classmates had the 28s and to be honest I was jealous of the alpha-numeric entry but just couldn't afford one.

The 41s were not on my list as I had not been exposed to them. After going to the Hpmuseum.org forums I learned a lot about them (and the other models) and found this great site and resources (though I should have signed up months ago). After finally picking up a 41 I understood. Its like someone trying to explain what a food tastes like but until that first bite one doesn't really doesn't have an accurate frame of reference.

Feel free to go on, there is nothing better than sincere enthusiasm.

Have a great one!
Bill
BillBee
...
...
 
Posts: 8
Joined: Tue Apr 20, 2021 2:06 pm

Re: "Extra' plastic piece fell out of 41C — Where does it go

Postby Jordan Orlando » Thu Apr 22, 2021 7:19 am

BillBee wrote:After finally picking up a 41 I understood. Its like someone trying to explain what a food tastes like but until that first bite one doesn't really doesn't have an accurate frame of reference.


Exactly. I don't think it's only nostalgia (although for me the nostalgia is a big part of it) or the aesthetics and vanguard engineering of Hewlett Packard — which were remarkable until they fell apart in the 80s/90s when, like IBM and so many other pioneers, they got supplanted by newer big companies and then "commoditized" (all those generic laptops and ink cartridges).

The jumps from the 9100A — HP's breakthrough innovation, the desktop computer ("calculator") that let anyone in a lab or at a university desk have his or her own machine that could do floating-point computations and transcendental functions — to the HP-35 (based on Bill Hewlett's insistence that the same thing be available to fit in his shirt pocket) to the programmable units in the next few years, to the magnetic-card-based world of the 65, 67 and 97...it's a fantastic series of steps, combining the straitlaced high standards of the old school engineering world with the consumer-electronics breakthroughs of the 1970s. But the 41C is when they abandoned those innovations to start over with a brand new technology, based on a full character set (thanks to a new display) and replacing all the mechanical/magnetic card readers with Atari-style ROM/RAM cartridges. It's my favorite kind of forward step: take what you, yourself, have invented (that put you on the top of the heap) and throw it away, because you can now see over the next horizon.
Jordan Orlando
......
......
 
Posts: 28
Joined: Sun Apr 04, 2021 11:16 am


Return to HP-41 Hardware

Who is online

Users browsing this forum: Semrush [Bot] and 1 guest

cron