Tropical Fish Caps

[Joe Hart]

I scavanged an old Hi-Fi, and got a bunch of old caps and resistors. Would they sound cool in a ToneBender? Are they worth anything? I know nothing about them, just that I've heard the name and when I saw these, I checked online, and they look like them! Thanks.
-Joe Hart

[Nasse]

They were popular when I was young and started to make mistakes. I think they are mostly polyester caps, quite o.k. for audio and rugged, and colour codes were easily available and easier to read than f****** small numbers of today.

I dont know why they disappeared, maybe it is cheaper to make caps like they make them today.

[bwanasonic]

Using parts for their aesthetic value when you plan on putting them in a metal box may seem silly, but I would like to have bunch of tropical fish caps only because they look cool. Anyone know of a NOS source (reasonably priced- not one of those places that sells *authentic NOS* pots for your tweed deluxe at $250 @)?

Kerry M

[BillyJ]

Do non electrolytic caps have any problems with being old?
If not I too would love to at least check these out.
Aren't they suppose to havre 'mojo' for lack of a better term?

[Ge_Whiz]

"Aren't they suppose to have 'mojo' for lack of a better term?"

What? Oh, behave!

[Peter Snowberg]

Do non electrolytic caps have any problems with being old?
If not I too would love to at least check these out.
Aren't they suppose to havre 'mojo' for lack of a better term?

"Paper and foil" caps eventually die. They didn't use acid free paper so it eventually breaks down and starts conducting. I think wet tantalum electrolytics also die; that's why they're all dry electrolyte tantalum now.

Now to get picky about names:  :wink:
The dry tantalum in the newer caps also is called an electrolyte. The common "electrolytic" cap is an aluminum electrolytic. They use water to keep hydrated (chemically wet) a layer of aluminum oxide on the positive plate of the cap. If the water leaks the plating gets damaged and the cap shorts and goes poof.

Mojo? That's the sound of a good capacitor. Try a film/foil type (polystyrene, polyester (mylar), polycarbonate, polywantacracker). Slightly lower on the pole are the metalized film caps, also in polyester, polycarbonate, and more polys.

-Peter