yet another noob here. answer is probably obvious for most but not for me really. Just wondering how to interpret markings on these capacitors (red circles)

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ps. first lesson learnt :)

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    \$\begingroup\$ These ain't resistors, rather capacitors. \$\endgroup\$ – Marko Buršič Oct 1 '19 at 15:00
  • \$\begingroup\$ Those are capacitors, and I read 220n K which I am not familiar with so I don't know if they are 220n Farad or 220nx1000 is 220u Farad. \$\endgroup\$ – Oldfart Oct 1 '19 at 15:02
  • \$\begingroup\$ What makes you think those are resistors? \$\endgroup\$ – Hearth Oct 1 '19 at 15:02
  • \$\begingroup\$ my bad, I thought its combination of both :/ just edited \$\endgroup\$ – user3328469 Oct 1 '19 at 15:04
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    \$\begingroup\$ I just noticed the line around the brown-black-brown silver resistor which means it is 100 Ohm. +/- 10% \$\endgroup\$ – Oldfart Oct 1 '19 at 15:22

Take a clue from the black silkscreen painted on the printed circuit board surface:

  • C as in C20 is some kind of capacitor. Most of those you've circled are not polarized and could be mounted either way.
  • R denotes a resistor - can be mounted either way.
  • T denotes a transistor, additional silkscreen show "E"(emitter), "B"(base), "C"(collector)
  • D denotes a diode. A silkscreen diode symbol shows which direction the cathode points.

The numbers following each letter allow multiple resistors to be uniquely identified...a schematic diagram would also show this letter followed by a number, and most often its value.

An example might be C4 220n...This is a capacitor, value 220 nanofarads. The silkscreen doesn't show the value, whereas the schematic diagram should.


There are at least two values that are printed on larger capacitors:

  • The value or size of the capcacitor, listed with a number followed by farads with units, like uF nF pF or sometimes mF. On smaller capacitors, the F is sometimes omitted.
  • The voltage rating, a number followed V. The voltage rating should not be exceeded or damage may occur.
  • Manufacturer codes (sometimes there, sometimes not) has codes for the manufacturer and can tell you what product line or even when it was manufactured.

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