Where is this kind of cap used?

[nenad88]

Google says its Metallized PET Stacked. I dont see this kind of cap often, where is it used?

An externally hosted image should be here but it was not working when we last tested it.

 

[ubergeeknz]

Seems they're primarily designed for switching power supply applications, they are supposed to offer low esr and good high frequency performance, as well as good storage capacity for volume

 

[nenad88]

Any chance someone can tell me which are these two big input caps and those 2 little between them?

 

[ubergeeknz]

The biguns are electrolytics. The littleuns will be poly film of some description.

 

[nenad88]

Nono, those two big behind pot.

 

[ubergeeknz]

Nono, those two big behind pot.

I see. Hard to say, I mean they look like the stacked film type but they could be anything. If I had to guess based on this appears to be a cheap chinesium thing, they're regular poly caps epoxied into a big can to look expensive.

 

[jan.didden]

Any chance someone can tell me which are these two big input caps and those 2 little between them?

You can't tell without a schematic or tracing the board to produce one. Big ones could be coupling. Then again, could be something else.
A cap provides a function that can be used in many places in a circuit.

BTW This type of cap is at least 40 years old. Polyester film caps. Used wherever a, well, cap, is needed ;-)
Someone found a NOS stash.

Jan

 

[lcsaszar]

It was produced by Siemens and used everywhere. I think it is good for audio coupling and power rail bypassing. It is made of metallized sheets of polyester (polyethylene terephthalate). But I better like the look of the WIMA MKS4... same material.

 

[jan.didden]

I see. Hard to say, I mean they look like the stacked film type but they could be anything. If I had to guess based on this appears to be a cheap chinesium thing, they're regular poly caps epoxied into a big can to look expensive.

No, I have a box of those. From Philips in the 1970's. Siemens made them also.
Good caps actually, low inductance because of the end metallisation, all cap elements in parallel.

Jan

 

[nenad88]

You can't tell without a schematic or tracing the board to produce one. Big ones could be coupling. Then again, could be something else.
A cap provides a function that can be used in many places in a circuit.

BTW This type of cap is at least 40 years old. Polyester film caps. Used wherever a, well, cap, is needed ;-)
Someone found a NOS stash.

Jan

Schematic is simple they are input audio capacitors and they are in parallel.

 

[nenad88]

I have found this in local store

47nF/400V | Silken Electronic

MKS, SIE, 10%, RM 5mm

An externally hosted image should be here but it was not working when we last tested it.

It looks much like those smaller caps.

 

[jan.didden]

Schematic is simple they are input audio capacitors and they are in parallel.

You mean coupling capacitors? Isn't this a stereo circuit?

Jan

 

[nenad88]

Yea coupling, I mean those 2 big are each in parallel with one smaller near them

 

[jan.didden]

Yea coupling, I mean those 2 big are each in parallel with one smaller near them

Ahh! Yes you see that often in an attempt to impress.

BTW You do know that there is no such thing as an 'audio capacitor', except for marketing purposes ;-)

Jan

 

[nenad88]

Yea I understand but still some are more audio friendly than others

 

[jan.didden]

I wouldn't know

Jan

 

[nenad88]

or not

 

[Mark Tillotson]

Google says its Metallized PET Stacked. I dont see this kind of cap often, where is it used?

An externally hosted image should be here but it was not working when we last tested it.

Looks like polycarbonate stacked film (low inductance), no longer obtainable I believe.

 

[nenad88]

Looks like polycarbonate stacked film (low inductance), no longer obtainable I believe.

Oh, You can get them https://www.newark.com/epcos/b32561j1105k000/polyester-film-capacitor-1uf-100v/dp/25M8103

 

[Mark Tillotson]

It turns out there are also polyester in this welded stacked package type, but when first introduced this was polycarbonate only. Polycarbonate dielectric film is no longer obtainable I believe. This package is a liability if you forget its got exposed metal and layout a pcb so that neighbouring components can short out. Much lower inductance than many film cap styles though.