Hi,
I haven´t hard of copper-film caps in SMD either.
Since the cap manufacturers rely on ´standard´ films, which are typically aluminum or zinc sputtered and since there´s no real advantage using copper in this application I doubt that anyone will manufacture such caps.
jauu
Calvin
I haven´t hard of copper-film caps in SMD either.
Since the cap manufacturers rely on ´standard´ films, which are typically aluminum or zinc sputtered and since there´s no real advantage using copper in this application I doubt that anyone will manufacture such caps.
jauu
Calvin
I'm mainly looking for SMD size types - and possibly small size copper foil/polypropylene/PTFE capacitors ...
Cheers,
Jesper
Hi Jesper,
I have been searching for the same kind of capacitors and I expect for the same usage. I can send you some samples of the four candidates I have settled on - two copper foil and two silver mica - no SMD parts, but relatively small in size and if hand soldering it is easy to use SMD pads on the PCB.
they are selling MLCC in NP0/C0G ceramic.
Nickel witch is a magnetic material (at room temperature) are used as the inner electrode.
And...
These devices are used in other sensitive analogue/digital equipment.
Correct...
And when I replace them with non-magnetic capacitors the equipment still performs as specified...
The only difference are that the SQ improves..
Really? Blind, level matched, ability to switch fast?
(you don't have to just ABX with short listening/fast switching but it does improve discrimination of some sound differences in controlled testing - so you really need the capability so you can compare on several time scales)
and its likely the actual inner electrodes in monolithic mlcc don't have Ni, some are even Ag – but there may be a barrier layer of Ni plating under the terminal plating to prevent leaching during soldering
(you don't have to just ABX with short listening/fast switching but it does improve discrimination of some sound differences in controlled testing - so you really need the capability so you can compare on several time scales)
and its likely the actual inner electrodes in monolithic mlcc don't have Ni, some are even Ag – but there may be a barrier layer of Ni plating under the terminal plating to prevent leaching during soldering
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apparently in a way that doesn't show in "conventional measurements" - like harmonic distortion at -140 dB downhow can a bit of nickel in a small cap affect an A.C. signal?
but there are components made for NMR machines – with no (ferro)magnetic materials at all
I will simply quote the results from Samuel Groner's thesis.
Distortion of capacitors at +20dBu on the capacitor, 1kHz
Polysyrene LCR components FSCEX 10nF - no visible harmonics above -153.4dB noise floor (none nada zilch)
Vishay MKP1837 PP film - same
Vishay COG/NPO - same, noise floor -142.5dB (ceramic BTW, this was 1nF which I assume is why the noise floor was higher)
Dick, I'm not being a trouble maker and I'm asking nice could you please show me schematically how to put a sine wave through a C with rectifying defects at the input to get the cancellation of distortion.
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but there are components made for NMR machines – with no (ferro)magnetic materials at all
Interesting - do you have any info / links?
Hi All,
- have just had a quite special morning riding my bike along the coast line of Aarhus where I live. The sun was rising and reflected against a thin layer of clouds with yellow/orange pastel colors. Wow! - I really find myself gifted living where I do ...
And then about the capacitors:
@RayCtech: Thanks (once more) for offering to help me with components I'll send you a PM about it shortly.
I've found these from Vishay that appear to be non-magnetic and possibly also have an interesting termination ("noble metals"):
http://www.vishay.com/docs/45128/vjnonmagneticseries.pdf
They're available in C0G types but as far as I can see not in a copper foil. Max value is 39 nF for the C0G types.
@jcx:
Hi jcx ... Might you have a link to Samuel Groner's "thesis"? I searched for it yesterday but didn't really find any ...
And then a thanks to all for considering my question by answering
Jesper
- have just had a quite special morning riding my bike along the coast line of Aarhus where I live. The sun was rising and reflected against a thin layer of clouds with yellow/orange pastel colors. Wow! - I really find myself gifted living where I do ...
And then about the capacitors:
@RayCtech: Thanks (once more) for offering to help me with components I'll send you a PM about it shortly.
Interesting - do you have any info / links?
I've found these from Vishay that appear to be non-magnetic and possibly also have an interesting termination ("noble metals"):
http://www.vishay.com/docs/45128/vjnonmagneticseries.pdf
They're available in C0G types but as far as I can see not in a copper foil. Max value is 39 nF for the C0G types.
@jcx:
Originally Posted by scott wurcer .... I will simply quote the results from Samuel Groner's thesis.
Hi jcx ... Might you have a link to Samuel Groner's "thesis"? I searched for it yesterday but didn't really find any ...
And then a thanks to all for considering my question by answering
Jesper
So nothing that is going to be audible.apparently in a way that doesn't show in "conventional measurements" - like harmonic distortion at -140 dB down
NMR machines create very strong magnetic fields, hence you don't want ferro-magnetic materials in there, audio is a bit different.
I would love to see some hard evidence of such a tint amount of nickel affecting the sound, in a way that is audible.
yes Vishay lists nonmagnetic parts
2010 Super 12
Syfer (Cu):
http://www.google.com/url?sa=t&rct=...-chadCa7CqISIC4Uw&sig2=CQbLI59Dpd4BOX1a6y8gfw
2010 Super 12
Syfer (Cu):
http://www.google.com/url?sa=t&rct=...-chadCa7CqISIC4Uw&sig2=CQbLI59Dpd4BOX1a6y8gfw
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So nothing that is going to be audible.
NMR machines create very strong magnetic fields, hence you don't want ferro-magnetic materials in there, audio is a bit different.
I would love to see some hard evidence of such a tint amount of nickel affecting the sound, in a way that is audible.
Harmonic distortion are the very least issue that matters...
@jcx: Thanks for the tip on the Syfer capacitors - looking into it ;-)
Cheers,
Jesper
As they use / can use different dielectric materials further investigations into this will be interesting..
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