I have opened my Sky Digibox which has stopped working and I am having problems reading capacitor values. For example, there are many blue blob type capacitors (ceramic dipped resin I guess) which I can't understand, for example, one has 221K
I then took it out and measures 1.4nF if I remember correctly. What does 221K mean? p.s. it was rated at 2kv - is that a switching psu? anyone knows how to troubleshoot those? (panasonic tu-dsb20)
try google "capacitor codes" ?
O.k. so what is 221K ?
The first link on google "capacitor codes" points to
"Now, what about the three numbers? It is somewhat similar to the resistor code. The first two are the 1st and 2nd significant digits and the third is a multiplier code. Most of the time the last digit tells you how many zeros to write after the first two digits, but the standard (EIA standard RS-198) has a couple of curves that you probably will never see. But just to be complete here it is in a table."
The single letter at the end is explained a bit further down the page.
It's the value in pF as follows. The first and second numbers are the first part of the value and the last digit is the number of trailing zeros.
So 221 = 220 pF
The K is a tolerance letter ( 10% ).
The cap you mention sounds like a snubber cap in a switch mode psu.
Graham
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