HP-28S battery door

[Maximilian Hohmann]

Hello!

(09-04-2018 07:30 PM)jonese Wrote:  Ideas on how do I can avoid the battery door issue? .

There is really only one thing you can do: Don't put batteries inside. I recently got another HP-19BII which looked as unused as yours. I wanted to put batteries inside to see if it works. As soon as I was about to close the battery door, the brown plastic started to turn white from the strain. One little more push and it would have cracked.

On this forum there are some tips about how to reduce the strain on the battery door. Among them:
. Look for the smallest possible N-cells. Not easy as one can be lucky to find these batteries at all.
. Put some tape around the cells to increase the friction inside the calculator housing thereby reducing the pressure on the battery door. Might actually work, however the correct amount of tape will be difficult to find out. Not enough and one achieves nothing, too much and the cells won't make contact. And in the worst case they may split the calculator housing, In any case they will be very difficult to remove.
. Replace the springs with weaker ones or cut off a couple of windings from the springs installed. Might work, but one has to take the calculator apart for that after which it will never be as before again.
- Power it from an external source through some self made battery replacements. This requires some DIY skills and will turn the machine from pocket to desktop calculator.

Maybe I missed some other options?

Regards
Max