Vishay ceramic cap markings (dull thread alert)

[timrobertson100]

Hi folks

I can't find anything on search about this, but today I became confused about ceramic capacitor markings.

I've got in front of me caps marked as 471k (I assume 10% 470pF) but also a Mouser bag labeled "Vishay 470pF" containing caps having a 470k marking.
At first, I assumed a Mouser error (wrong part in bag) and then discovered I also have 750pF and 120pF labeled bags with 750k and 120k markings on them.

I then find I have a 4th Mouser bag labeled Vishay 390pF, but those are marked as 391k.

Using the manufacturer part number on the Mouser bags I've discovered two Vishway docs:

1. This one (last page) does indeed state the caps carry a label of the pF value and they give an example "680 = 680pF"
2. This one says it follows the EIA 198 where 391k is a 10% 390pF

Can it be that similar-looking parts from one manufacturer follow different marking schemes or am I tired and missing something?
How do others identify their caps in the pF range (my DMM doesn't work so low) if they've ended up out of the packaging and mixed in a tray, please?

Thank you.

[martin manning]

The k is 10% tolerance. 390 and 391 could be the same thing. 391 is surely 39 x 10^1 = 390pF, but small caps are often marked with the pF value, so 390 could be 390pF, or it could be 39 x 10^0 = 39 pF. Mouser might just be eliminating the uncertainty by writing 390pF on the bag.

[timrobertson100]

but small caps are often marked with the pF value

Thanks, Martin - that is very helpful.

[Stevem]

Weather repairing or building I dont trust anything these days, I go by what my tester read out tells me, even for resistors.

[timrobertson100]

Thanks Steve - do you do this for things in the 10-100s pF range, and if so, how please?

(Edited to add: I see a peak LCR45 meter at reasonable price I might invest in)

[sluckey]

I bought this cheap Proster LCR meter for the exact reason you are considering one. I checked some small caps and inductors I have in benchstock. Seems to be accurate enough for my use. I haven't had a real world reason to use it though.

[maxkracht]

https://www.amazon.com/HiLetgo-Multifun ... 521&sr=8-3

These only go to 25pf but test transistors/diodes as well. There are versions with a case, and some with a color lcd display. The one I tried with the color screen was really slow but maybe the newer ones are better. I have a DE-5000 for more accuracy, but I usually reach for the cheap one.

[martin manning]

Same here, I have a fancy LCR meter, but the $20 component tester is good enough for a quick verification of the value from reading the marking. Caps under 47p are rarely encountered in audio circuits.

[timrobertson100]

Thank you all for the replies and help.

I'm surprised that markings are not consistent, even from one manufacturer, but I'm really happy to learn what others do.

I've ordered the Peak LCR45 for 82€ + VAT - should be able to measure within a few pF's and certainly distinguish things 10x apart

[Edited to add: The LCR45 is small, came with 2 batteries, is very quick to measure in auto mode, and is giving readings close to all my pF caps in the 10 and 100s range. I'd recommend it]