What is this component?

I recently took up an interest in selling kits for my instructable "The Light Theremin." However upon ordering the exact parts I realized I still don't know what type of capacitor I used! When I built it I assumed from its size that it was 1.0uF, and judging from the lack of complaints on the instructable I must be somewhat right. Here is all the information i know and can provide...

- its marked "104" on one side
- It is a ceramic disk capacitor.
- light brown in color.
- and seems to work well in an experiment around 9 volts direct current.

Here is a link to my instructable: https://www.instructables.com/id/Light-Theremin/

Thank You!

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TXTCLA55 (author) 6 years ago
Thank you all for your help!
6 years ago

See AndyGadget's link, or the Wikipedia article on capacitor markings. The three-digit codes are a compact "exponential notation:" xyz == (xy) × 10z, with a base unit of picofarads (pF).

Your capacitor is marked "104", which becomes 10 × 104 = 10 × 10000 = 100,000 pF = 0.1 µF.

jensenr306 years ago
Any capacitor marked "104" will have a capacitance of 100,000 nano-farads (or 0.1 uf) When discerning the code written on ceramics, do the following.
• Treat the first two numbers as one number. (10)
• Now take that number (10) times 10^(the third number)
• since the third number is 4, we get the following equation:   10 x 10^4.
• This of course equals 100,000, and thus, 100,000 nf.
we can apply this to other ceramic caps too!
take for instance, the 473 ceramic capacitor.
cap 473 = 47 x 10^3 = 47,000

frollard6 years ago
I do believe you are correct, 104 = 1.0x10^4 nF = 1000 nF = 1uF
6 years ago
You've dropped two zeros and added three :-) The first two digits are the mantissa, so "104" actually means 10 × 104, or 100,000 (not 1,000). Also, the base unit for those three-digit codes is pF, not nF. The net result is 0.1 µF.
6 years ago
I knew someone would jump in :) I thought the 2 digits was 1 and 1 of precision...good to know :)
steveastrouk6 years ago
100nF, 0.1uF

Steve