dF 96 — electrolytic capacitors also have inductance from the foil winding.
The larger the cap typically the higher the inductance, the inductance limits the slew rate of current flow especially at higher frequencies. Smaller caps = lower inductance = faster response. But you knew all that...........
Best to use bipolar electrolytics , and two back to back bipolars is even better.
See Cyril Bateman‘s extensive capacitor tests.
https://linearaudio.nl/sites/linear...0 to 100uF caps and 100 Hz measurements_0.pdf
The larger the cap typically the higher the inductance, the inductance limits the slew rate of current flow especially at higher frequencies. Smaller caps = lower inductance = faster response. But you knew all that...........
Best to use bipolar electrolytics , and two back to back bipolars is even better.
See Cyril Bateman‘s extensive capacitor tests.
https://linearaudio.nl/sites/linear...0 to 100uF caps and 100 Hz measurements_0.pdf
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Dave,
As mentioned before, respectfully, our experiences differ. I myself am still waiting for any acceptable sign/utterance from the OP to convince me that he is not simply trolling. finish. If he feels hurt by that (seeing that he seems to be taking long leave), fine. Who said that life (or its participants) are fair...... Perhaps some have learnt from this thread where doubt existed before (I do not mean regarding the OP; we have done. I mean regarding electronic principles.)
Frecrowder,
For ideal caps, yes one can. Point is that where electrolytics have been used as coupling caps, hopefully there was a d.c. difference between the coupling points, otherwise why not use non-polars from the start? But there is a distinct difference in leakage current between electrolytics of whatever kind and say polyester or such - that is what Tony implied. In fact, the only reason for using electrolytics at all is still size.
Imagine using a say 1000µF 450V polyester capacitor for filtering/coupling. Excellent - but the size (if manufactured at all)? As Tony implied, all capacitors have greatly decreased in size as well as increased in efficiency. But still 'horses for courses'.
________________________________________________________________________
P.S:
Frecrowder,
Apology! My reply above is to your post #38. Seems I have overlooked the subsequent contributions since! Still. Non-polar/bi-polar capacitors also have inductance, but I have never found such bothersome in any electrolytic unless the circuit is - er - rather sensitive.
.......and I can thoroughly recommend the mentioned series by Cyril Bateman!
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The largest film cap available at 600-650V from DigiKey is this: https://www.digikey.ca/products/en?keywords=C44UHGT6600G8TK
It's non-stock and you need to buy 50 of them for almost 12 grand...
It's non-stock and you need to buy 50 of them for almost 12 grand...
... unless I throw one at your head!
But, seriously, if it is established that Arjock just comes here to troll, why not just kick him off the premise? We've got enough amusement here as it is.
Jan
Is that the origin of the term 'flying capacitor'?... unless I throw one at your head!
... unless I throw one at your head!
Interested in capacitor **speed**???
Couldn´t find exactly that but Lithium Battery speed ... literally; results should be real close
Will 2000 FPS be fast enough?
These funny/crazy guys shoot *anything* (and I mean ANYTHING) out of their shotgun barrels, as long as it fits inside a 12 Ga shell.
Here they shoot 123 type Lithium cells, and I´m certain some capacitors (both electrolytic and film) will fit there too, so results should be comparable.
YouTube
I only fear showing this video will spark yet another fierce battle about capacitors ... including a bunch of snake oil or wholly subjective claims
. . . since we're having fun, how about using a capacitor or two to speed a projectile on its way?
450J Coil Gun
YouTube
When I worked at Philips in Eindhoven, we used something like that to initiate newcomers.
We would put a large electrolytic under his chair, wired to a mains variac.
Wait till the unsuspecting victim was in the middle of a measurement and then slowly turn up the variac until first it starts smelling foul, then thick smoke starts to rise, finally (often, not always) a big bang.
Worked every time ;-)
As he said, don't try this at home!
Jan
We would put a large electrolytic under his chair, wired to a mains variac.
Wait till the unsuspecting victim was in the middle of a measurement and then slowly turn up the variac until first it starts smelling foul, then thick smoke starts to rise, finally (often, not always) a big bang.
Worked every time ;-)
As he said, don't try this at home!
Jan
We used to wire big electrolytics into the mains point all along a bench. Then wait until the apprentice came in and flicked the breaker to turn the whole bench on.... bangbangbang!! That really woke people up!!We had another guy who used to build real rat's nests of prototypes - 3d sculptures. Someone drilled a small hole through his bench, attached a long bit of thin tube. Then, would blow smoke through the tube at critical moments. Took him ages to figure out it wasn't his circuit...
Like the old adage - "electronics runs on smoke. You can tell this as when the smoke gets out, it stops working".....
I used to do this. Except instead of a 55 gallon drum I used a pop bottle.
6V-25V cap, connected to 120VAC... Like an electric cherry bomb
If I had a nickel for every time I tripped a breaker blowing up caps, I'd be a happy guy.
Never had a stones to use 240VAC though
But sadly, I now have fuses instead of breakers and don't like paying for replacements
For those interested in the results for the series cap. Here they are. No I will not be replying.
Setup
6cg7 tube with a constant current source
DC Bias mid 200 volt range
DC filter .2uf cap 100K to ground .15uf cap 100K to ground
DC bias leaked through the second cap is 0.5mv as measured by my HP3478A
Down 1.9dB at 30hz as compared to 1kHz. This was expected and is fine for this application
10Khz square wave is nice and clean
1kHz is ok but is affected by the 30hz response
Setup
6cg7 tube with a constant current source
DC Bias mid 200 volt range
DC filter .2uf cap 100K to ground .15uf cap 100K to ground
DC bias leaked through the second cap is 0.5mv as measured by my HP3478A
Down 1.9dB at 30hz as compared to 1kHz. This was expected and is fine for this application
10Khz square wave is nice and clean
1kHz is ok but is affected by the 30hz response
Generally:
Not sure of the application (the attached images would not open). Where such small voltages were measured in a basic grid coupling circuit, it might well have been caused by electrons landing on the grid, not necessarily capacitor leakage per sé. The latter is best measured in a passive circuit. In capacitor coupled circuits it is normal to measure a few mV on the grid, depending on the measuring topology and circuit values.
Not sure of the application (the attached images would not open). Where such small voltages were measured in a basic grid coupling circuit, it might well have been caused by electrons landing on the grid, not necessarily capacitor leakage per sé. The latter is best measured in a passive circuit. In capacitor coupled circuits it is normal to measure a few mV on the grid, depending on the measuring topology and circuit values.
cap leakage causes red plating....in a Fisher 500 receiver i repaired, the culprit was a coupling cap, replaced with a fresh one and problem fixed...
wrt coupling caps, i learned from the gurus here that one should use the minimum value of coupling cap that one can get away with...
wrt coupling caps, i learned from the gurus here that one should use the minimum value of coupling cap that one can get away with...