HP41c Zebra - last tests

[Jose Gonzalez Divasson]

Hi,

We have been using elastomeric zebras for the connection between keyboard circuit and processor of the HP41c. These worked more or less well - until some more current was required (updating a CL, using a card reader). The higher resistance (a factor of 20 more than the original part 1251-5731) was the cause.

Following the work of Mark Fleming, we designed a smaller part that so far works very well. We are now trying to find what is the best fill for the connector tubes, to provide support with flexibility, but good connection is achieved even with nothing inside: the nice "MEMORY LOST" message appears immediately. You can see the pictures in the attached files.

   

As soon as we have settled on the fill, we'll publish it!