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spice repair

shown here is an illustrated disassembly of an hp-32e calculator, one of several spice models.
many thanks to tony duell for showing me how to do this.

take off the battery cover and remove the battery pack. undo the two small screws at the top.

the unit wont open because there is a catch inside the case at the base. adopt the special grip shown here and push up with the thumbs and pull back with the hands so as to pull the case twowards you.
the case should click open.

now remove the back and put it aside.
carefully lift out the battery pack connector taking care not to damage the ribbon cable.

 
there are six small lugs that hold in place the main circuitry of the machine. you need to prise these away carefully, often  simultaneously. the lift out the main circuit unit.

take care here not to disturb the keycaps underneath. you might like to make a keycap diagram before this stage incase some of the keycaps fall out of place.
here are the back of the keycaps and the underside of the circuit board.

be careful not to lose the small metal on switch.
i look the opportunity here to scrape some oxide from the switch.

see here the circuit board. its a solderless construction held together by two spring clips one down each side.
the spring clips are asymmetrical. carefully prise open the underside and they fall away.
when separating the board, be careful that the chips dont fall out! (hint: the notches face the top of the unit).

see here the main cpu (larger) and two small rom chips. some models have a third.

the other board is the power supply.

 
here is the underside of the circuit that contacts the chips.

re-assembly is easy. clip the spring clips back in place. maintain an even pressure on the board to prevent the chips dislodging whilst you put in place the second clip.
clip the foot back first, it will snap in place.