The "What Kind Of Caps Are These" Thread

[YetiHunter]

Some old yet everlasting adages for starters:

Do it right the first time.
Stop, ask questions first.
There are no dumb questions, only arrogant mistakes.

Am I on the right track?

So, for the sake of learning, I'm going to put up some pictures of capacitors,
and hopefully someone can tell me what they are.

I'm going to start with some tantalums that I'm questioning my value readings
on.

Am I going in the right direction?

First and second stripes are the value digits, stripes/dots are the multipliers,
final band is the voltage. Correct?

Exhibit A: Yellow, Purple, Yellow, blue stripe... what's with the green leg ?
Exhibit B: Brown, black, blue, green stripe
Exhibit C: Yellow, Purple, blue, brown stripe
Exhibit D: Yellow, purple, yellow, blue stripe

This is my guess...

A: um... 47 uf 6.3v or 16v....or ????
B: 1uf 20v
C: 470pf / .47nf 20v
D: 47uf 6.3 v

Now the important questions.

Some of these tantalums are on power rails, should those be replaced with electrolytics?

Is it good practice to replace tantalums in the audio path one every 30-40 years?

That's it for round 1.

[YetiHunter]

Round 2

These are polyester caps?

Exhibit A: Yellow Purple Orange White Red Brown
Exhibit B: Brown Black Yellow Black Red Brown


Exhibit A: 47 nf ... 20 v +/- 10% ?
Exhibit B: .1 uf .... 20v +/- 20% ?

[YetiHunter]

Foil Tantalum? Wet Tantalum? Electrolytic?

[YetiHunter]

Polyester film capacitor on top.
What's the story on the Sprague?

[YetiHunter]

What is this?

[YetiHunter]

What is this?

[nucelar]

Originally Posted by YetiHunter

That's it for round 1.

What Kind Of Caps Are These?
Round 1 are obviously DANCING caps

[YetiHunter]

I got an e-mail from my solder monkey friend that went like this...

"I FOUND ONE!"

<see attachment>

[drtechno]

before capacitor companies had to conform to printing numbers on their capacitors, some used color codes. and they differed between manufacturers too on the tantalums,

the polypropylene used standard color code for numbers from the the top to bottom it was first number, second number, multiplier (in picofarads), tolerance.

on the tantalums I remember, the stripe down side was voltage indicated positive lead

and the "legs" were colored positive and negative tolerance, positive tolerance on the voltage stripe side.

you shouldn't have to replace those tantalum caps unless you are having issues with voltage sags or noise. tantalums usually don't go bad unless you subject them to temperature extremes. If they are part of an EQ on a mixer, then I'd change them every 10 years so the eqs are constant across different channels on the mixer.

I'll look and see if I had some of the old "standards" capacitor color value charts.

the red-orange spauges were 5% precision poly caps

the black kement is a solid tantalum cap, pointed tip positive

silver one with black letters, electrolytic crimp rim indicated positive if not marked positive lead

silver one with red numbers, tantalum, value in nanofarads, stripe indicated positive lead

round 2 polypropylene caps .047 uf and .1 uf body measurement dictated voltage rating.

[YetiHunter]

Thanks friend.

For reference, this is what I was working off of

Capacitors

[dualflip]

The first one are tantals, the second ones are polyester film, the fourth seems to be an axial electrolytic, i think its the same as the fourth pic, axial electrolytic, the next one is also an axial electrolytic, the kemmet i dont know, havent seen one like that

Capacitors: Types, Specs, notes on Use "Capacitors: A Field Guide to Types and Habitats" - by Harry R. Bissell Jr.

That link may help you out...