SOLVED: W&W Rambox 32k current drain

[Hiwi]

Hi all,
the problem is solved. There was one of the blocking smd ceramic c defect. It has some resistance about 2-3 kOhm so there was a current drain even when the box was shut down. The internal battery and the battery of the HP-41 went empty within a couple of days.

I obtained the box as a gift from a collector's friend. The box was sold over ebay some month ago. Sold as fully functional, only empty battery at a yery huge price about 400$. Thats more than new! It was announced with something like "Last time I was using it, it worked" :-) But it turned out, that it was broken.

I found out, that it s a 64K Box , not only 32k!

There are 3 types of Ramboxes in the magnetic card reader case

First generation was build with over 24 discret ic's from the 4000 series. This is the 32k only version.
Second generation from 1888/89 was build on a foil circuit board with a custom made gate array and ram. 32k and 8k chips (8bit+2bit = 10bit needed for the HP-41)
There are 32k and 64k Versions. The additional Ram was mounted on the top of the foil

Third generation, especially for the Halfnuts (which has a different power management)
has 3 stacked circuit boards with gatearray and 64k Ram.

Ralf