Jim, These are non-polarized (or bi-polar) electrolytics. An example is the following digikey part number: 493-12697-3-ND
You can always whip one up out of your junk box - just put 2 normal (polarized) electrolytic in series with the polarities alternating (for example, connect the two positives together). Each capacitor has to be twice the value of the result - so for example, to replace a 1uF 50v non-polarized, you can put two 2uF in series. Hope this helps. Ian > On Jul 30, 2016, at 10:24 PM, Jim Brain <br...@jbrain.com> wrote: > > Since I acquired a Coco Orchestra 90 unit awhile back, and I am trying to > find the source of some humming in my system when the Orch 90 unit is > operational, I looked at the schematic: > > > http://www.colorcomputerarchive.com/coco/Documents/Manuals/Hardware/Orchestra-90%20CC%20Stereo%20Music%20Synthesizer%20(Tandy).pdf > > > (page 109 of the PDF) > > I understand the ROM, the resistor ladders, and the latches, but analog is > not my strong suit. I made my way through the op-amp design, but I am > stumped on one component (actually three)? > > > C7,C9, and C10 > > They look like electrolytic polarized caps, but are NP (non polarized), with > no '+' on the schematic. > > > Can someone shed light on what these are and where you would find them (or if > they can safely be replaced with another kind of capacitor)? I will admit > I've never seen mention of these before now. > > Are they "bipolar"? > > http://www.digikey.com/product-detail/en/nichicon/UVP1H010MDD/UVP1H010MDD-ND/242804 > > > Or, are they called something else now? > > Jim > > > > > > -- > Jim Brain > br...@jbrain.com > www.jbrain.com > > > > --- > Filter service subscribers can train this email as spam or not-spam here: > http://my.email-as.net/spamham/cgi-bin/learn.pl?messageid=3CDFF5C056DF11E6946E026893ED0201
