1944GPW
Veteran Member
I bought this Compaq LTE notebook back in 1991 and used it for some years as a portable terminal, running Kermit to talk to NCR Tower / Unisys 5000 machines when I went onsite at my customers installations. After my dad used it for a few years, it went into the cupboard for many years until I rediscovered it recently and brought it home. I plugged it in and the power supply went click-click-click but after a dozen power cycle events it started up. Unfortunately the hard disk seems faulty now, and attempting to load the LTE diagnostics floppy resulted in nothing happening.
I disassembled the machine and found the floppy drive belt was now just a broken sliver of gooey rubber that had stuck to the motor and spindle pulleys. Being natural rubber and only 2.3mm wide and 0.28mm thick it was exceedingly fragile, after picking it off with tweezers this was all that was left of it:
I tried seeing if a regular 3.5" floppy drive would work, but the LTE drive was about 3/4 the height of all the regular drives I had in my parts lot and to compound matters it also used a film ribbon connector instead of a plug. So that ruled out a repair with a drive that would fit into the laptop case.
The drive belt path ran the belt around a fixed idler pulley, to get it clear of some components on the circuit board and to also clear the head impinges upon.
After cleaning the remains of the melted belt off the pulleys with isopropyl alcohol, I tried a rubber band:
With this arrangement the spindle pulley turned, but only slowly. The rubber band was far too thick and rubbed against itself at the idler - a thinner belt was mandatory.
Thinking back thirty something years, my S-100 machine had a TEAC FD-50A 5-1/4" floppy drive hanging off a VersaFloppy controller. I recalled the FD-50A had a simple untensioned belt that looked like a loop of cassette leader tape stretched between the motor and spindle pulleys, and I always wondered at the time how the belt didn't stretch and fall off. Perhaps something like that would work?
I measured a cassette tape but unfortunately the width was far too wide and would have rubbed on the board. It was also narrow enough to cause problems trimming to the required width.
So I decided to cut a strip to the required width of 2.3mm from a VHS video tape. I wanted some metres of it for experimentation in joining the ends with different adhesives.
I disassembled the machine and found the floppy drive belt was now just a broken sliver of gooey rubber that had stuck to the motor and spindle pulleys. Being natural rubber and only 2.3mm wide and 0.28mm thick it was exceedingly fragile, after picking it off with tweezers this was all that was left of it:
I tried seeing if a regular 3.5" floppy drive would work, but the LTE drive was about 3/4 the height of all the regular drives I had in my parts lot and to compound matters it also used a film ribbon connector instead of a plug. So that ruled out a repair with a drive that would fit into the laptop case.
The drive belt path ran the belt around a fixed idler pulley, to get it clear of some components on the circuit board and to also clear the head impinges upon.
After cleaning the remains of the melted belt off the pulleys with isopropyl alcohol, I tried a rubber band:
With this arrangement the spindle pulley turned, but only slowly. The rubber band was far too thick and rubbed against itself at the idler - a thinner belt was mandatory.
Thinking back thirty something years, my S-100 machine had a TEAC FD-50A 5-1/4" floppy drive hanging off a VersaFloppy controller. I recalled the FD-50A had a simple untensioned belt that looked like a loop of cassette leader tape stretched between the motor and spindle pulleys, and I always wondered at the time how the belt didn't stretch and fall off. Perhaps something like that would work?
I measured a cassette tape but unfortunately the width was far too wide and would have rubbed on the board. It was also narrow enough to cause problems trimming to the required width.
So I decided to cut a strip to the required width of 2.3mm from a VHS video tape. I wanted some metres of it for experimentation in joining the ends with different adhesives.