I am reorganising my hobby electronics workplace and have found a box of axial leaded capacitors that all look the same, apart from their size and marking. They are silver with transparent ends, no hint of maker or obvious type number; the biggest, about 10mm long body, 4mm diameter, is marked 470J 125YS.

I am trying to reduce by 3/4 the amount of stuff I have hoarded over the years, and in the process my capacitance meter is still somewhere under the heap to be sorted, so I can't determine the capacitance of most of them yet.

My question is: what type of capacitor are they, and are they cheap enough to dump, or valuable and difficult to replace?


1 Answer 1


They sound like polystyrene capacitors: -

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If they are I'd hang on to them - they are generally quite a stable type of cap and mostly they are better than 5% tolerance (I think that's what the J is in your question). Not as good a dielectric as C0G/NP0 but not far off. Usable in good quality filters for audio and signals.

  • \$\begingroup\$ Definitely good for audio or radio. Main downside is the low melting point of polystyrene : exercise some care when soldering. \$\endgroup\$
    – user16324
    Commented Feb 1, 2014 at 20:09
  • \$\begingroup\$ These things are amazing; I wish i had a good source for them locally. \$\endgroup\$
    – Wyatt Ward
    Commented Feb 1, 2014 at 21:22
  • \$\begingroup\$ Thank you @Andy for that answer, just what I wanted to know, and apologies for not making this comment sooner. \$\endgroup\$ Commented Feb 4, 2014 at 17:30

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