I have found some capacitors like this one:
Does anyone know what kind of capacitor it is? How can I read its value?
Capacitor Identification – What Kind of Capacitor is This? How to Read Its Value Code?
capacitoridentification
Related Solutions
Without specific examples (i.e. links to the circuits you found) it's hard to give an authoritative answer.
In general:
Capacitors specified with no polarity (no + and -) and no voltage rating are usually ceramic types, and common voltage ratings (25V, 50V) should be fine.
Capacitors that show polarity are polarized types - usually electrolytic, sometimes tantanlum. Substitution with ceramic or other types usually isn't possible as the capacitance needed may require many in parallel. Polarized capacitors in the tens of microfarads or higher are generally electrolytic. Lower values could be electrolytic or tanatalum.
A voltage rating is a helpful hint. Never place a cap with a lower voltage rating where a higher voltage rating is indicated. A good guideline is to choose the capacitor with voltage rating, which is twice the nominal voltage across the capacitor in the circuit. High voltage, small values (picofarads to a few nanofarads) are generally ceramic; high voltage with higher values (tens of nanofarads and up) are often metal film or polypropylene capacitors.
Capacitors that say X, Y, X# (i.e. X2) or Y# (i.e. Y1) are safety-critical and must be special ceramic or film capacitors that bear safety markings (UL, TUV, etc.)
The photo is helpful. I suspect it's a Chinese part that is numbered similarly to the Panasonic FP series.
That would make it a 220\$\mu\$F/50V 105°C RoHS low-impedance part, size code "G" (10mm⌀\$\times 10.2\$mm tall)
Of course if it's not a genuine Panasonic part (and I don't think it is, the markings don't look like the Panasonic parts I have) the characteristics may not be the same (and chances are they will be, at best, equal).
Best Answer
These images appear to have your answer. This capacitor is a 0.01µF 250v capacitor from old electronic equipment (most likely radio, audio, or television related) containing vacuum tubes. It is similar looking to some of these which are old mica capacitors:
The stripes on the capacitor can be interpreted using the standard resistor color code to give a 3-digit code like on standard capacitors, where the third digit is the multiplier. In order to read the capacitor code, simply multiply the number created by the first 2 digits by 10multiplier to get the final value in pF.
With resistors, the last stripe indicates the tolerance, but with older capacitors it indicates the voltage. If a tolerance is not specified, it is usually 20%.