Texas Instruments

Model: TI-59
Battery: BP1 A
Adapter: AC9131 or DC9105
Year: 1980
Chip: TMC0501E TMC0582 TMC0583 TMC0571 TMC0594  4x TMC0598    
Info: TI-58 / 59 programmable        

TI-58 or TI-59 calculator this rare Marine Navigation version uses a specialized module with navigation related programs. The calculator was mounted in a expensive wooden box and equipped with a DC-converter for usage on a boat. 

The TI-58 and TI-59 calculators introduced a novelty, the Solid State Software Modules™ with up to 5000 program steps. On the backside of the TI-58/59 you'll note a small lid with a place for a module. The Master Library, known as "Module -1-", with 25 different programs was included with the TI-58, TI-58C, and TI-59. Twelve additional Solid State Software Modules™, known as "Module -2- to -13-" were available from Texas Instruments as Standard Modules.

TroubleShooting

Card reader with replacement of the licorice wheel... As promised the photos. I used the 7 mm external and 3 mm internal tube, in some cases I had to use the 6 mm one (SR series), since you disassemble everything, clean all the gears and then use a lithium grease (little I recommend). Since you have to disassemble everything, clean the magnetic head with isopropyl alcohol.