transiently permanent:
Canon Palmtronic LE-81M, 1974
transiently permanent:
Casio Memory A-1
transiently permanent:
TI SR-16, 1974
transiently permanent:
Tealtronic K-80M (Type 1), c 1972
transiently permanent:
Casio model 121-E, 1973
transiently permanent:
Decimo VATMAN calculator
transiently permanent:
Texas Instruments TI-1250 calculator
transiently permanent:
Texas 1025 calculator
transiently permanent:
Brinlock Abacus
transiently permanent:
Brinlock Abacus calculator
transiently permanent:
Triton 1400 calculator by Radofin
transiently permanent:
Adler 80c
transiently permanent:
Sinclair Cambridge type 3
transiently permanent:
Sinclair Cambridge Scientific, 1974
transiently permanent:
Sinclair Cambridge Programmable, 1976
transiently permanent:
HP 35
transiently permanent:
TI Datamath
transiently permanent:
TI Datamath II
transiently permanent:
TI Datamath II
transiently permanent:
Hewlett Packard HP35, 1973
transiently permanent:
Texas Instruments Programmable 57
transiently permanent:
TI SR-40
transiently permanent:
Sharp Elsimate EL-8117K, 1977
transiently permanent:
Accuron calculator c1977/8?
transiently permanent:
Triton calculator 1974-5?
transiently permanent:
TI-1250
transiently permanent:
Decimo Vatman Mini M2, c.1977/8
transiently permanent:
Binatone Memory Master M, 1976 or 77
transiently permanent:
Casio Personal Mini, 1975
transiently permanent:
Commodore scientific calculators. SR7919 (left) and 899D, both 1976