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Got this machine since a long time ago, in dismantled state and waiting to be repaired.
Today morning I decided it was time to start emptying the dismantled machines drawer, so I picked the one at the top of the pile. I have another model with similar build documented here.

The only issue with this 1976 machine was the battery compartment that had oxidation in the power switch/battery terminal assembly. The machine was sold as non working.

According to the Instruction Manual, this calculator takes two AA dry batteries, or the optional Ni-Cd battery pack EA-18B and the Ni-Cd Recharger model EA-17E.
Look to Katie Wasserman site for the manual.

After cleaning all the parts to remove the battery electrolytes products, it was time to repair, test and assemble it.

[Image: sharp_el-5800_001.jpg]

Single chip machine: Hitachi HD36125
Display Futaba 9-ST-12

[Image: sharp_el-5800_002.jpg] [Image: sharp_el-5800_003.jpg] [Image: sharp_el-5800_005.jpg]

Keyboard assemblage.
Note the metal spring interconnecting the front metal face plate with the keyboard metal frame assembly.

[Image: sharp_el-5800_006.jpg] [Image: sharp_el-5800_007.jpg] [Image: sharp_el-5800_008.jpg]

The keyboard PCA snaps over the keyboard membrane and two screws fix it securely in place.

[Image: sharp_el-5800_009.jpg]

Heavy battery corrosion has damaged the positive terminal in the battery compartment.
I have these miniature battery terminals at hand, so have trimmed one of them and soldered it to the original remaining terminal.
Could not do a clean job though, as the plastic assembly is soft and started to melt when soldering.
I was too lazy to dismantle the whole set in order to be able to do a cleaner job.
Still it is mechanically and electrically working fine now, despite the ugly looks.

[Image: sharp_el-5800_010.jpg]

After power on. Current consumption = 62mA
All digits lit. Current consumption = 80mA

[Image: sharp_el-5800_011.jpg]

Main PCA folded and in place.

[Image: sharp_el-5800_013.jpg]

Cover installed. It snaps at 10 different points (latches). It takes just one screw.

[Image: sharp_el-5800_014.jpg] [Image: sharp_el-5800_15.jpg]

Forensics test - asin(acos(atan(tan(cos(sin(9))))))result:

[Image: sharp_el-5800_017.jpg]

Error condition on display: SQRT(-2):
All zeros and all decimal points lit.

[Image: sharp_el-5800_018.jpg]

Despite being boxy, it is still a nice looking machine.

[Image: sharp_el-5800_019.jpg]

This is the package I got.

[Image: sharp_el-5800_020.jpg] [Image: sharp_el-5800_021.jpg]
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