could someone please identify this component for me?

[Liam O'Rourke]

hi Could someone please tell what the cuboid shaped beige components in the attached image are please?
The ones with the black writing that says '1j63' on them and the one with '33j63' on it.
Thanks a lot

 

[Minder]

0.1μf and 0.33uF capacitors .
M.

 

[Liam O'Rourke]

thanks a lot. is there a name for the style of component? ie. electrolytic, ceramic etc.
thanks

 

[Minder]

Probably ceramic.
Max.

 

[Liam O'Rourke]

ceramic? Surely there is a name that would differentiate them from the more common type of ceramic capacitor. Ie... the disk style ones

 

[davenn]

ceramic? Surely there is a name that would differentiate them from the more common type of ceramic capacitor. Ie... the disk style ones

definitely not ceramic
they are more likely to be mylar or polyprop. most likely the later


Dave

 

[Liam O'Rourke]

so

definitely not ceramic
they are more likely to be mylar or polyprop. most likely the later


Dave

yeah i dint think theyd be ceramic i just said that cus 'minder' said they were. Anyways... thanks again

 

[hevans1944]

hi Could someone please tell what the cuboid shaped beige components in the attached image are please?
The ones with the black writing that says '1j63' on them and the one with '33j63' on it.
Thanks a lot

They appear to be 0.1 μF and 0.33 μF, respectively, metalized plastic-film capacitors. Plastic film can be a lot of things, but Mylar and polypropylene are common, as @davenn stated. There are dozens of others. At the capacitance given, definitely not mica... too small in size and mica is usually encapsulated in a different material. These are either by-pass or timing capacitors. Quality and reliability of this type of capacitor is usually high. For timing use, the dielectric has to be a low-absorption type for good repeatability. This Wikipedia article has a good discussion and pictures of example types.

 

[davenn]

but Mylar and polypropylene are common, as @Liam O'Rourke stated

as I stated

 

[hevans1944]

as I stated

Oops. Fixed it.

 

[davenn]

At the capacitance given, definitely not mica... too small in size and mica is usually encapsulated in a different material.

out of curiosity, have you seen silver mica caps ?
They can be VERY small down to at least a 1/4 of the size of those caps in the photo. Ones I commonly use
are from a few 10's of pF to a few 100's of pF

mica is usually encapsulated in a different material.

Yes, the SMica ones are usually dipped in a brown resin

I scrounge everyone I can get off old boards, treat them like gold ... difficult to buy.
Used in RF Transmitter circuits, very stable under temperature



Dave

 

[hevans1944]

Hundreds of picofarads for mica capacitors is common. A few microfarads is unheard of. I have a transmitter mica stashed away somewhere that is good for a few dozen amperes of RF current. It is mounted in a three or four inch diameter ceramic cylinder with heavy metal mounting plates/electrodes on the ends. If I can find it, I'll take a photo and post it here. At one time I thought it might make a good DC blocking cap for a high-power amateur radio final amplifier... not that I would deliberately run it at ten kilowatts output power... that would be illegal, except perhaps into a dummy load.

And, yeah, I treasure dipped silvered mica capacitors too. I don't know what the resin is, but it is really tough stuff... some sort of epoxy maybe.

 

[Andy Dowell]

Generally, in the Eighties, Digikey reffered to them as Plessey box capacitors. I see them referred to as metalized polyester - but more research might be made to confirm.

33j63 would be .33 uF, "j" is tolerance of 5 (or 10)% _I forget which), and 63 is voltage.

a