Page 1 of 1

The Capacitor Site: "I Equals C*dV/dt" iequalscdvdt.com

Posted: Sat Feb 16, 2019 5:06 pm
by mediatechnology
This site started out as a simple exercise in web page making that sort of got out of control. Once I started writing, I found it hard to stop.
Everything you ever wanted to know about capacitors:

The Capacitor Site: "I Equals C(dV/dt)" http://iequalscdvdt.com

Re: The Capacitor Site: "I Equals C*dV/dt" iequalscdvdt.com

Posted: Sun Feb 17, 2019 1:19 am
by brianroth
What a great link, Wayne! For me, it's a refresher course as well as a lot of "....hmmm learned something new today"

Interesting coincidence, but in the past week or so I discovered a new line of TDK branded MLCC C0G/NPO caps in axial/thru-hole packages at Mouser. I just messed with the Mouser filters, and they stock up to 0.22 uF ($1.32 in singles, 5 mm lead spacing, which is kinda small for that amount of uF).

Reading about C0G caps in audio applications ( see John Hardy's website and elsewhere) I tend to no longer hate ceramics...LOL.

Bri

Re: The Capacitor Site: "I Equals C*dV/dt" iequalscdvdt.com

Posted: Sun Feb 17, 2019 12:34 pm
by Gold
I’m closing in on finishing building my T-filter EQ’s. I’m using polystyrene caps for the lower value in the tuning sections.

I want to try using C0G ceramics in those positions in the Barry Porter SVF EQ instead of Polypropylene or polystyrene.

Re: The Capacitor Site: "I Equals C*dV/dt" iequalscdvdt.com

Posted: Sun Feb 17, 2019 3:51 pm
by JR.
I love polystyrene and used piles of them in my kit company back in the 70's -80's, but they were not robust enough for large scale manufacturing processes.

NPO/COG ceramic will be suitably neutral (linear) and more robust.

JR

Re: The Capacitor Site: "I Equals C*dV/dt" iequalscdvdt.com

Posted: Sun Feb 17, 2019 4:53 pm
by Gold
The polystyrene sound good. The low band needs a 4.7uf and a 3.3 nf All Electronics has some large values for cheap. I got 100pcs of 5000pf for $7.50. Two in parallel and one in series gets me to 3.333nf. I actually got 200 pcs and hand selected to nail the absolute value. I never would have figured that out without the handy Electronic Toolbox Pro.