HP-28S for parts/renovation

[grsbanks]

I have an HP-28S going for parts.

This unit has seen better days. As with most of these clamshells, it no longer has a battery door. There is also some battery leakage in the compartment.

The left keyboard is fine. The right keyboard feels somewhat "mushy". Disassembly of the unit has been attempted (not by me!) and given that the label above the screen and the overlay surrounding the keys of the right-hand keyboard are in good condition, my guess is that someone did this with a crowbar and the heat stakes are toast.

This is a "Made in USA" unit and the serial number puts its manufacture at week 7, 1989. This is the variant with the shiny LCD.

Despite the state of the shell, if you put batteries in the unit and fit a temporary battery door, the calculator does power up and operate, albeit very slowly, and the self test comes back OK. There is some life yet in the old gal and someone might like to take her on as a renovation project.

Photos here on Flickr

What do I want in return? I'm about to inherit an HP-15C that's lost its badge and an HP-16C with a case of LCD bleed, so i'm looking for dead Voyager units. Ideally a dead HP-15C (original design with the Nut CPU that runs off three LR44 batteries) that can serve as a donor of its badge and its LCD.

[Massimo Gnerucci]

(12-31-2017 09:50 PM)grsbanks Wrote:  (original design with the Nut CPU that runs off two LR44 batteries)

I fear that you'll need three of them.

[grsbanks]

(12-31-2017 10:47 PM)Massimo Gnerucci Wrote:  I fear that you'll need three of them.

Yep. I realized that after I went to bed last night I've now edited the original post.