# novice question

• posted

hi all, i'm building a small electronics project which was bought in kit form... bear with me i'm a beginner ;) everything is soldered onto the board except for a few components i'm not sure about... there are places on the board left for 4x 1microF capacitors (the tiny ones which aren't polarity sensitive- not sure the proper name!) i have 4x capacitors with just the number "105" on them left over- do you think they have sent the wrong capacitors or is "105" actually a 1microF capacitor?

there are also 9 places on the board left for 9x 100nF capacitors... i have

9x capacitors with the number "104" left over - are these the wrong ones?

many thanks!! andy

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"Andy C" wrote in news:qCjHh.14168\$ snipped-for-privacy@text.news.blueyonder.co.uk:

*snip*

Capacitors are labeled funny. (To me, at least.) What I usually do is search for "104 capacitor" via Google, and often I get a page with the value of the capacitor. If you're doing a lot of work with capacitors, you'll want to learn the codes. If it's just a "now and then" thing, there's no need.

Puckdropper

```--
Wise is the man who attempts to answer his question before asking it.

To email me directly, send a message to puckdropper (at) fastmail.fm```
• posted

Yes, the 105 means a 10 followed by 5 zeroes or 1,000,000pF (pico-Farads) which is exactly equal to 1uF (micro-Farad), or even 1,000nF (nano-Farads)

Those are the correct caps. 104 is 10 followed by 4 zeroes or 100,000pF which is the same has 100nF and .1uF. Does that help?

• posted

Hi, Andy. You're doing fine -- your caps marked 105 are 1uF, and the

104s are 0.1uF or 100nF caps. You can complete your kit with the parts you have.

This is a common newbie question. For many good answers to your question, go to Google Groups s.e.b. and search in that group for the phrase capacitor codes (no quotes).

Congratulations on getting the parts right. That's not the easiest thing for a newbie. Hope everything works OK. If not, feel free to post again -- be sure to mention the kit manufacturer and kit number

-- it helps.

Cheers Chris

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thank you! don't know why i didn't think of that !!

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Ceramic capacitors are often marked with their values in picofarads, using a three digit code: two digits plus a multiplier.

Your "105" capacitor is 1, 0, 00000 pF, or 1,000,000 pF which equals 1 uF. the "104" parts are 0.1 uF or 100 nF or 100,000 pF.

```--
Peter Bennett, VE7CEI  Vancouver BC, Canada
peterbb4 (at) interchange.ubc.ca  ```
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Use of milli-Farads can be confusing and/or hazardous.

In ancient times, before the Greek alphabet was invented, we used "mF" or "MF" to mean microfarad (and mmf for micro-micro farad, now called picofarad), so using mF for millifarad will confuse many older techs, and mislead newer techs looking at old schematics.

```--
Peter Bennett, VE7CEI  Vancouver BC, Canada
peterbb4 (at) interchange.ubc.ca  ```
• posted

You're right, and I just saw a schematic using mF for uF, why oh why.

• posted