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What is this electrical component? Answered

Can anyone tell me what this is? and if so a good site to by it. thank you!


Yep, as Burf says, a ceramic capacitor. And as frollard says, get them at any of the on-line sites he suggests. You may even be able to get them at a local Radio Shack (might have to tell them you need an electronic part, not a part for a cell phone :/  ). If you have a choice, get a Z series with a voltage rating of 500V or 1KV, seeing as it is being used in a tube situation. Here's a PDF on them.



6 years ago

Sorry but that is more then a capacitor, it is also a break over arc device
called a gap cap to prevent a high voltage from exceeding an upper limit
as the air gap clearly visible on the top of the component establishes.
Very useful in high voltage electron tube circuitry as noted by the old style
hardware sockets evident in the picture frame...


Would you happen to know were to get one?

DigiKey, Allied, Newark comes to mind but I never needed a gap-cap,
so I cant be sure they carry the item.
I have some in my parts box that's how know what they are.

Never ran across them. I found a place (westfloridacomponents.com) that has one (1) value of them (470pF) but that wont help here. The others you mentioned don't carry the GAP-CAP brand/variant. What could you combine with a standard ceramic cap to emulate the GAP-CAP?


Thanks everyone for the quick answers.


6 years ago

Its a ceramic disc capacitor.


ANY electronics website will carry them.

You can get one-offs on ebay...usually cheapest to buy them in the 1000's...
digikey, mouser, newark all sell them individually.