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HP Forum Archive 21

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HP-28--better design?
Message #1 Posted by Matt Agajanian on 21 June 2012, 1:38 p.m.

Hi all.

Having used a 28C and 28S, I am pleased with its UI and ease of program development. My main hurdle comes not from program debugging but from replacing batteries. Yup. that's right! Replacing batteries. It's as if I need to be a gymnast, acrobat or have ten fingers on each hand. Between pressing down the batteries against a super springy spring, placing the battery door in the groove and then sliding the door in place, I am EXHAUSTED. Feels like I should get a gold medal for accomplishing such a convoluted procedure.

So, my question is the obvious: Could the 28 have been designed with a more practical backside battery compartment & door akin to the 48 and 50 series?

      
Re: HP-28--better design?
Message #2 Posted by M. Joury on 21 June 2012, 1:44 p.m.,
in response to message #1 by Matt Agajanian

It was. Some very few later models have a back-side door that appears way more convenient and robust. I, unfortunately, have never managed to acquire one of these units as they seem to be in somewhat higher demand than the regular ones and I have only seen a couple on eBay. Never been quite willing to bid high enough to snag one.

Cheers,

-Marwan

      
Re: HP-28--better design?
Message #3 Posted by Thomas Radtke on 21 June 2012, 1:45 p.m.,
in response to message #1 by Matt Agajanian

Function follows form here. It would be fine if only this compartement wouldn't be so fragile.

Later 19BII had an improved battery compartement design.

            
Re: HP-28--better design?
Message #4 Posted by M. Joury on 21 June 2012, 2:03 p.m.,
in response to message #3 by Thomas Radtke

Good point. I don't know that I have ever actually seen a 28S with that design. Maybe it was only the 17bii.

Cheers,

-Marwan

      
Re: HP-28--better design?
Message #5 Posted by Namir on 21 June 2012, 5:44 p.m.,
in response to message #1 by Matt Agajanian

I was never a big fan of the clam-shell models even though the 28S/C first implemented RPL. The original battery door was and remains a poor deign issue. I read that the contact between the two parts of clam-shell machines wore with usage.

I was more of a fan of the HP-48SX and the machines that followed as they packed a lot of math punch in them.

Namir

      
Re: HP-28--better design?
Message #6 Posted by Palmer O. Hanson, Jr. on 21 June 2012, 9:40 p.m.,
in response to message #1 by Matt Agajanian

Today I purchased an HP-18C for two dollars at a garage sale. I don't know where the owner had found it but he couldn't get it to work. He apparently didn't know about the door at all. When I got it home I opened the door and found that there were two adequate cells in one slot, but the other slot was empty. When I installed the needed cell the calculator booted up and seems to be running properly. The battery door shows no sign of wear. That's different from my HP-28S which I also purchased for two dollars. It's battery door was cracked and part was even missing. The owner said he was selling it for two dollars because he just wanted to get the damn thing out of the house. Apparently, he had lost a lot of work wnen he lost all memory while fiddling with the battery door. I practiced with the door before using the 28S and convinced myself that I could work quickly enough to save memory. A couple of years later I lost everything when I had trouble replacing the door.

      
Re: HP-28--better design?
Message #7 Posted by Eddie W. Shore on 25 June 2012, 3:47 p.m.,
in response to message #1 by Matt Agajanian

Quote:
Hi all.

Having used a 28C and 28S, I am pleased with its UI and ease of program development. My main hurdle comes not from program debugging but from replacing batteries. Yup. that's right! Replacing batteries. It's as if I need to be a gymnast, acrobat or have ten fingers on each hand. Between pressing down the batteries against a super springy spring, placing the battery door in the groove and then sliding the door in place, I am EXHAUSTED. Feels like I should get a gold medal for accomplishing such a convoluted procedure.

So, my question is the obvious: Could the 28 have been designed with a more practical backside battery compartment & door akin to the 48 and 50 series?


Having just got one (28C), I agree with you Matt about with the batteries. A practical door would make the 28 better. And I don't have gold medals or I would send one to you. :)

      
Re: HP-28--better design?
Message #8 Posted by David Tellet on 27 June 2012, 9:27 a.m.,
in response to message #1 by Matt Agajanian

Agreed, not a great design, but mine is still intact after 25 years of moderate use so I don't think it is a fatal flaw - just a clear weakness. Seems like the 28 gets short shrift because of the clamshell and the battery door---kind of a shame since I think the rest of it has a lot to offer. And the separated keyboard and menus do make for a cleaner primary keyboard, imho.


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