Brooke, you have been busy. I assume you refer to #28 as a candidate comparison. Either way it is clear that an ESR reading of 50 is very bad. I think I will go with like for like. That is 1uf non-polarised electrolytic. Cheers Justin On Tue, Apr 23, 2019 at 2:54 AM Brooke Clarke wrote: > Hi Justin: > > Here's a table with measured ESR for a wide variety of capacitors. #28 is > a 1uF Orange Drop (FRS OMB1MFD). > https://prc68.com/I/Capacitors.shtml#Tbl > > -- > Have Fun, > > Brooke Clarke > https://www.PRC68.com > http://www.end2partygovernment.com/2012Issues.html > axioms: > 1. The extent to which you can fix or improve something will be limited b= y > how well you understand how it works. > 2. Everybody, with no exceptions, holds false beliefs. > > > Date: Mon, 22 Apr 2019 20:16:39 +0800 > > From: Justin Richards > > Subject: [EE] Typical ESR for 1uF non-polarised cap > > To: "Microcontroller discussion list - Public." > > Message-ID: > > < > CAKMvr86HwJUw4u6tD+zaa39MWbVuekq6Jq738rz0vXV1o-yUOA@mail.gmail.com> > > Content-Type: text/plain; charset=3D"utf-8" > > > > Can I use a ceramic 1uF cap to replace a 1uF non-polarised electrolytic > in > > the final stage of a woofer driver? > > > > What should a typical ESR range be for a 1uF non-polarised electrolytic= ? > > > > Details:- > > A Behringer B115W requires replacement 1uF non-polarised caps. > > > > The original electrolytics measured approx 50ohms ESR. I haven't been > able > > to find anything definitive regarding ESR values for non-polarised > > electrolytic except to find a reference to them having generally higher > ESR > > than their polarised counter parts. However, I have to assume 50ohms E= SR > > is really bad. > > > > Trawling the archives I found this from Olin "...There is really no pla= ce > > left today for a 1uF electrolytic capacitor..." > > > > In the B115W these caps (c33 and c34 if the attachment made it) are use= d > to > > connect the two woofer drive traces to ground. They appear just before > the > > final inductor/transformer. > > > > [image: image.png] > > > > What say ye. > > > > Justin > > -------------- next part -------------- > > A non-text attachment was scrubbed... > > Name: image.png > > Type: image/png > > Size: 12289 bytes > > Desc: not available > > Url : > http://mailman.mit.edu/mailman/private/piclist/attachments/20190422/297a2= 961/attachment.png > > > > ------------------------------ > > > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .