Yes, they can do this with a lot of noise and sometimes also setting things on fire .

Here a similar situation I had with a 486 board. Fixing these caps is usually not that difficult, if you can read and find out the specs ...

UM486V - Capacitor Specs

It's close to a mounting screw, maybe someone carelessly jammed a screwdriver in there while trying to remove the board and destroyed the capacitor.

Recently I got a board with damage near one of the mounting holes, so this post reminded me of that...

cyclone3d wrote on 2026-03-14, 02:41:

Just got a Tandy 1000A computer. Looking it over during the process of cleaning it up before trying to power it on, I noticed a damaged / blown ceramic capacitor next to the printer port.

Has anybody ever seen a ceramic capacitor do this before? I am wondering if it was just damaged or if it actually blew. There are no scorch marks or anything so not sure what to think.

The attachment 22J_capacitor-cropped.jpg is no longer available

I can't say I've ever seen a ceramic cap explode, and if it was caused by too much voltage due to another fault I would expect it to be burnt. This looks very clean, so I'm inclined to blame it on physical damage. The insulation around the leg on the right is also cracked and those caps are all pretty bent looking, like they were beat on at some point.

Still, it is odd to have that kind of damage inside a computer, rather than on a board pulled from a scrap lot. Maybe if this cap's purpose isn't integral to the function of the computer it could have happened during assembly and been that way for 40 years.

Aui wrote on 2026-03-14, 06:43:

Yes, they can do this with a lot of noise and sometimes also setting things on fire .

Here a similar situation I had with a 486 board. Fixing these caps is usually not that difficult, if you can read and find out the specs ...

UM486V - Capacitor Specs

That is a tantalum capacitor and is a completely different thing. They are known to explode or shoot out sparks or smoke when they fail. Ceramic capacitors are not known to do this.

ok thx - I learned something new!

Ozzuneoj wrote on 2026-03-14, 07:19:

I can't say I've ever seen a ceramic cap explode, and if it was caused by too much voltage due to another fault I would expect i […]
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cyclone3d wrote on 2026-03-14, 02:41:

Just got a Tandy 1000A computer. Looking it over during the process of cleaning it up before trying to power it on, I noticed a damaged / blown ceramic capacitor next to the printer port.

Has anybody ever seen a ceramic capacitor do this before? I am wondering if it was just damaged or if it actually blew. There are no scorch marks or anything so not sure what to think.

The attachment 22J_capacitor-cropped.jpg is no longer available

I can't say I've ever seen a ceramic cap explode, and if it was caused by too much voltage due to another fault I would expect it to be burnt. This looks very clean, so I'm inclined to blame it on physical damage. The insulation around the leg on the right is also cracked and those caps are all pretty bent looking, like they were beat on at some point.

Still, it is odd to have that kind of damage inside a computer, rather than on a board pulled from a scrap lot. Maybe if this cap's purpose isn't integral to the function of the computer it could have happened during assembly and been that way for 40 years.

Aui wrote on 2026-03-14, 06:43:

Yes, they can do this with a lot of noise and sometimes also setting things on fire .

Here a similar situation I had with a 486 board. Fixing these caps is usually not that difficult, if you can read and find out the specs ...

UM486V - Capacitor Specs

That is a tantalum capacitor and is a completely different thing. They are known to explode or shoot out sparks or smoke when they fail. Ceramic capacitors are not known to do this.

All the ceramic caps on the board were laid down flat from the factory. I bent those ones up so I could get a better look at the damaged one. After looking at it more, I am inclined to think that whoever put it together got the tip of that cap under the screw head that is seen in the picture and damaged it during assembly.

There is no continuity between the legs of that capacitor and it is just for the printer port so I should be ok to power it up.

I did order an assortment of ceramic capacitors since that was one of the things I didn't already have on hand and it will get replaced once they arrive.