Page 1 of 2

Schematic

Posted: Mon Mar 24, 2003 4:34 am
by Mike
I am used to eading the symbol for a capacitor that looks like this:<p>---+)|----<p>I recently found a circuit I would like to build that uses symbols that look like two rectangles next to each other. I have figured out that if both are black, it needs a non-polarized capacitor and if one is white and one is black it needs a polarized. But what I don't know is which side is which. what is white and what is black.<p>The schematic is in the subject "lm383" in the folder "general" there is a link in there to a datasheet. The one I would like to build is pasge 8, fig 16. Thanks.

Re: Schematic

Posted: Mon Mar 24, 2003 5:34 am
by bridgen
The white, or hollow, one is the positive plate.<p>In the one you have drawn the straight plate is the positive.

Re: Schematic

Posted: Tue Mar 25, 2003 4:32 am
by Mike
Thanks, but the one that I can't read is the one that is two rectangles put together and one is shaded black, and one is shaded white. Which side is which? is black negative and white positive, or is it the opposite. I already know how to read the one below<p>--+)|--<p>Thanks

Re: Schematic

Posted: Tue Mar 25, 2003 2:42 pm
by greg123
I think what dave is trying to say is that the one you have drawn is incorrect.<p>--+)|--<p>It should be like this:<p>---)|+-

Re: Schematic

Posted: Wed Mar 26, 2003 2:02 am
by gadgeteer
I wouldn't go much over-voltage-ratinged with an electrolytic; they have a bad habit of changing values if you severely under-drive them.<p>Drive a 20µF 110V at 6 volts, you may find it has changed to 5µF after a while...

Re: Schematic

Posted: Thu Mar 27, 2003 4:37 am
by Mike
Can somebody PLEASE answer MY question? I don't care about the other junk. I simply want to know how to read the symbol. I KNOW HOW TO READ THIS ONE! :mad: <p>---)|---<p>NOW CAN SOMEBODY TELL ME HOW TO READ THE ONE THAT IS TWO RECTANGLES NEXT TO EACH OTHER. ONE IS BLACK AND THE OTHER ISN'T FILLED. WHICH ONE IS WHICH? CAN SOMEBODY JUST LOOK AT THE PAGE I SAID IN THE FIRST POST?

Re: Schematic

Posted: Thu Mar 27, 2003 5:35 am
by L. Daniel Rosa
From the schematic, I'd assume that solid is negative.

Re: Schematic

Posted: Thu Mar 27, 2003 5:45 am
by bridgen
Mike,
the black (filled) plate is the negative one, the white (hollow) one is the positive one.
Sorry, I thought my original post would have been sufficient.

Re: Schematic

Posted: Thu Mar 27, 2003 6:32 am
by Ron H
David, I don't think an apology from you is in order. One from Mike might be nice. Your first post was clear to me.<p>Ron

Re: Schematic

Posted: Thu Mar 27, 2003 7:37 am
by frhrwa
I agree with RonH.. an apology from MikeA is in order.. going balistic on everyone when they are offering you free help, then adding to it by shouting.. you'll find a kind thank you for the extra info works better in the future!

Re: Schematic

Posted: Thu Mar 27, 2003 10:47 am
by Chris Smith
In Electronics black should always be neg, or ground. However in house hold wiring and AC black is hot. So unless your wiring your home, black is neg, cold, or ground, but not neutral! Why any one would mention values for the cap, also got by me? You were clear in your asking. I think the Japaneese do the little rectangles instead of the plates?

Re: Schematic

Posted: Thu Mar 27, 2003 11:50 am
by greg123
Mike,<p>Dave bridgen did answer your question in the second post.<p>"the white one is positive"<p>No need to flip<p>[ March 27, 2003: Message edited by: Greg ]</p>

Re: Schematic

Posted: Thu Mar 27, 2003 2:42 pm
by Ron H
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by 1206DX:
You are refering to a specifice data sheet you are specifying National Semiconductor part.
A datasheet is the part manufacturer's specifications.<p>National Semi does not use any color code. <p>The symbol is a non-polar capacitor.

The other JUNK is more specific discription for someone who does'nt know how to read a schematic for the part that you described. There are 6 pdf pages of details on the data sheet to date. I described only the information you made reference to. <p>I think the JUNK you refer to is an expression of your unwillingness to let go of the fantasy electronic self image and explore the reality of electronic schematics and enjoy it and it's details.<p>[ March 27, 2003: Message edited by: 1206DX ]
<hr></blockquote><p>1206DX, even though the subject of the other thread was LM383, the link was as follows:<p>"See Fig. 16 of the datasheet:
http://www.unisonic.com.tw/products/icpdf7/TDA2030A.pdf "<p>I was the one who posted that link for Mike, which he says he "found".<p>Ron

Re: Schematic

Posted: Thu Mar 27, 2003 2:47 pm
by bodgy
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by Chris Smith:
In Electronics black should always be neg, or ground. However in house hold wiring and AC black is hot. So unless your wiring your home, black is neg, cold, or ground, but not neutral!<hr></blockquote><p>Just to be a smarty - that colour coding only applies to non European/AU/NZ/SG and Hong Kong wiring systems.<p>The rectangular way of drawing caps is the IEEE /European way.<p>Just don't pick up a copy of Elektor mag that uses IEEE standard for drawing logic gates - just shows what happens when a committee gets to design a symbol.<p>Colin

Re: Schematic

Posted: Thu Mar 27, 2003 7:02 pm
by Mike
Ok, Ok, I'm sorry. I wrote that at 6 in the morning while half asleep and was a little angry then that, although you were helping, I wasn't getting an answer. I'm really sorry for getting you all mad. Please forgive me. Also, thank you for answering my question. Again, I'm very sorry about that.<p>- Mike