Trimble 4000 Series Software

These files were recovered from a set of disks that came with a Trimble 7400 I bought on eBay. The floppies had been stored inside the airtight Trimble carrying case along with the receiver, which I soon discovered had suffered from a catastrophic lithium battery failure.

The outgassing of the lithium battery into the airtight carrying case seems to have damaged the floppy disks, with the portion exposed at the shutter suffering the worst. None of the floppies were readable. After multiple attempts with different drives, I gave up hope and shelved the disks.

A few months later, I learned about the Greaseweazle; this is a small board with a USB interface that can be connected to a floppy drive. It supports flux level imaging of floppy disks. It was also unsuccessful at imaging the disks, but during my process of trial-and-error, I noticed that the number of failed sectors was dropping with each subsequent imaging pass. I quickly realized that there must have been some sort of residue on the surface of the disk, that was being 'scrubbed' from the surface of the disk with subsequent imaging passes. After a few failed attempts, I was able to extract 100% accurate captures of a number of disks, as found below.