HP41C s/n 1932A00199

[Jose Gonzalez Divasson]

Hi,

I am now in awe, repairing a customer HP41c with serial number 1932A00199, together with a card reader 2029S45402.

When putting a different processor, the power off happens in 45 seconds instead of 5 min! Also the processor has a different texture to later units (even tall keys)

The top plate in the keyboard is nearly perfect too.

I am trying to post pictures but I can't...


   

[Diego Diaz]

Hi,

This is caused by the different display boards. Early units used a timer for the auto-OFF feature with a different capacitor (C2) value than those in the latter units.

You have to replace that capacitor in the CPU board, from 470pF to 10nF and you'll get the standard auto-OFF delay.

Hope this helps.

Best from Canary Islands.

Diego.

[Jose Gonzalez Divasson]

Thanks!