Simple Ceramic Capacitor questions - Page 1
Forum section: electronics / beginners

author: CircuitQuest
author_rank: Contributor
timestamp: October 05, 2023, 05:25:54 pm
content: I have a ceramic capacitor on a radio from 1981 (Sanyo M1700F) that is chipped and I want to replace it. The code on it reads 223 with no underline and has KCK under it.So based on what I have read 223 = 0.0022uf. But all the examples have an underline underneath the223and I don't know what KCK means.So my noob questions are.1. if there is not an underline does that mean the capacitor is not 0.0022uf?2. If the underline does not matter then is the voltage rating the same for all caps reading 223?3. Is the KCK a voltage rating code or just a manufacturer code?4. I cant seem to find 223 ceramic caps on Amazon (Canada). There are kits with 222, 224 and 225. Is there a reason why 223 would not be included in these kits? Just wondering if 223 is a special type of capThanks

author: wasedadoc
author_rank: Super Contributor
timestamp: October 05, 2023, 05:40:17 pm
content: Quote from: CircuitQuest on October 05, 2023, 05:25:54 pmNo. 223 means 22 followed by 3 zeros picofarad. 22,000 pF which is 22nF which is 0.022uF. Ten times larger than you concluded.

author: TimFox
author_rank: Super Contributor
timestamp: October 05, 2023, 05:45:58 pm
content: Disc ceramic capacitors are no longer popular.However, Mouser lists 9 different 22 nF disc ceramic capacitors, of which 3 are in plentiful stock, 2 are expected shortly, and 4 are not stocked.

author: Vovk_Z
author_rank: Super Contributor
timestamp: October 05, 2023, 05:53:27 pm
content: I guess other kinds of ceramic caps can be used too, and possibly non-ceramic types too (it depends on a role it is doing in the circuit).I guess there isn't large voltage anywhere in the whole radio so you don't have to concern about capacitor rated voltage. Anything >16 VDC should be fine.

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: October 05, 2023, 06:04:21 pm
content: If it works, leave it alone. The chip in the package may not be affecting its capacitance.

author: Zero999
author_rank: Super Contributor
timestamp: October 05, 2023, 06:23:12 pm
content: The chip appears to have exposed some of the metal plates. It's possible it's short circuited it or reduced the capacitance slightly. If it still works, then you can leave it, but I would be concerned it might be more vulnerable to failing later on, as moisture could get into it.

author: wasedadoc
author_rank: Super Contributor
timestamp: October 05, 2023, 06:34:32 pm
content: Quote from: Zero999 on October 05, 2023, 06:23:12 pmIf it is working OK, apply clear or coloured varnish* to seal the chip. Your other half, gf etc is likely to have something for her nails. Avoid any with glitter particles as those might be metallic.(* Maybe known as nail polish in some parts of the world.)

author: wraper
author_rank: Unknown
timestamp: October 05, 2023, 06:44:26 pm
content: Quote from: Zero999 on October 05, 2023, 06:23:12 pmWith disc capacitor shorting is very unlikely, plates are too far away and chip probably is not even large enough to reach metal plating. There is no real need to replace it, but it can be replaced with leaded MLCC ceramic cap which are more common even though phased out too due to TH assembly becoming obsolete for most of things. Power supplies remaining among a few of things where it still makes sense.

author: CircuitQuest
author_rank: Contributor
timestamp: October 05, 2023, 06:44:48 pm
content: Oops added an extra 0.