I am a very new hobbyist to vintage computer repair/maintenance, mostly as a way to rekindle the excitement I felt when I discovered computers way back then. I’m picking up the machines I owned/used back then and integrating them into my modern workflow as a writer.

Anyway…in trying to diagnose issues with a Toshiba T1000 laptop (circa 1987), I’ve narrowed one problem to the power block. One part in particular was loose on the board. Its legs were soldered tight; they were actually loose inside the part. So I pulled it for testing. But I have no idea what it is, so I don’t know if I’m testing it correctly. If it’s a resistor, it’s shorted, since it reads 000.0 on my MM. But I can’t find any current parts that look like this (cement?) and bear these markings. In fact I’ve only found fuses identified like this, but they don’t look similar. Anyway, I’d appreciate any help/info.

BTW, as far as I can tell, Toshiba never published the schematics or a parts list for this machine.

 

It's a fuse. You can confirm this by working out where it is in the circuit. The form factor isn't important, the ratings are.

 

Could it be of the thermal type?

 

It's a fuse. You can confirm this by working out where it is in the circuit.

Thank you! Fuse makes sense, since it may be one of the first components in the power block. (The T1000 PCB is very tightly packed, front and back.)

I was thrown by the fact that it’s encased in cement, and I couldn’t find any modern fuses like it.

 

Thank you! Fuse makes sense, since it may be one of the first components in the power block. (The T1000 PCB is very tightly packed, front and back.)

I was thrown by the fact that it’s encased in cement, and I couldn’t find any modern fuses like it.

There have been improvements in the materials that are available for components and space is at a premium, so...

 

Could it be of the thermal type?

It is.

 

Search for Thermal cutout or thermal cutoff or just thermal fuse. The ones I have look like the second picture.
" 250V2.5A 130C Thermal Cutoff Fuse "
"uxcell Thermal Fuse 125V 2.5A 130 C"

 

There have been improvements in the materials that are available for components and space is at a premium, so...

I’ve just ordered some replacements!
Thanks so much for your very fast and helpful replies. I really do appreciate it.

Bob

 

Search for Thermal cutout or thermal cutoff or just thermal fuse. The ones I have look like the second picture.
" 250V2.5A 130C Thermal Cutoff Fuse "
"uxcell Thermal Fuse 125V 2.5A 130 C"
View attachment 241730
View attachment 241731
View attachment 241732

Thank you!!

Bob

 

hi rm,
E


Update:
BTW These are Bi-metal Temerature cut out switches.