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HP28S Battery Hatch Solution
02-03-2020, 05:02 PM (This post was last modified: 02-03-2020 05:44 PM by edryer.)
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HP28S Battery Hatch Solution
I have moved this to its own thread to stop the clutter on the thread regarding HP28/clamshells case opening/closing.

Because the the 28C/S and most of the other clamshells have an issue with the battery door I have been looking at solutions.

1. Burkhards solution of using 3 x 2/3 AAA flat-top is probably the best (esp. in terms of battery life).

2. The alternate solution of using some small wood (or other material) surrounded by aluminum foil and coupled with alternate batteries of 1.2V - 1.5V - these could be anything from watch cells to 1/3 AAA size cells. I saw somebody do this.

I had the materials handy for the latter so I attempted it.

Not only does it work but the pressure on the battery hatch is almost zero. That is no pressure at all. Best of all it seems to work fine!

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HP-28S (1988 US model), DM41X (2020)
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HP28S Battery Hatch Solution - edryer - 02-03-2020 05:02 PM

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