If the hard drive is not starting in your PowerBook 100, it may be because the main battery has gone bad. Like the Mac Portable it is based on, the PowerBook 100 relies on a bit of an extra "kick" from the lead acid battery to get the hard drive up and running - even when it's plugged in to a power point.
Some people on here have reported that their PB100s start up ok without the battery. My PB100, like my Mac Portable, does not. I don't know of any source for replacement PB100 batteries and they don't lend themselves to easy repacking like the Mac Portable batteries.
My somewhat ugly solution to running up my PB100 has been to take a small 6v lead acid "gel cell" type battery and connect it to the PB100 battery terminals using fairly sturdy cables and insulated crocodile clips. You can hold the crocodile clips open and guide them in through the battery slot to the standard connectors using needle nosed pliers if you are patient and careful. Make sure you get the polarity right amd don't short them out to anything else (or to the conductive EMI shield coating on the inside of the plastic case)!
Some people on here have reported that their PB100s start up ok without the battery. My PB100, like my Mac Portable, does not. I don't know of any source for replacement PB100 batteries and they don't lend themselves to easy repacking like the Mac Portable batteries.
My somewhat ugly solution to running up my PB100 has been to take a small 6v lead acid "gel cell" type battery and connect it to the PB100 battery terminals using fairly sturdy cables and insulated crocodile clips. You can hold the crocodile clips open and guide them in through the battery slot to the standard connectors using needle nosed pliers if you are patient and careful. Make sure you get the polarity right amd don't short them out to anything else (or to the conductive EMI shield coating on the inside of the plastic case)!