EasyFace question about a capacitor

Started by daren, July 11, 2006, 07:08:02 PM

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daren

I tried building the Tonepad EasyFace and gave it up last year (didn't work, didn't have time, etc.) It's here:
http://www.tonepad.com/project.asp?id=19

But now I've picked it up and hope to finish it this week. I just noticed that the ONE thing that I have in my parts that is incorrect is the 0.01uF capacitor is NOT polarized.

So, is it really important for the capacitor to be polarized?
If it is, can I somehow solve this problem by sticking a diode in the way or should I just go to the store to buy the capacitor?
I actually went to my University store that sells parts and the guy who retrieved my parts said he was pretty sure there isn't such a thing as a polarized capacitor, but I'd like to check with you guys.

jeroen_verbeeck

#1
There are polarised capacitors, we call them electrolytic caps. They look like This. Mind the 3 "-" signs going down the side.

We also have ceramic and metalfilm caps (and more), they look like this and this. Those are not polarised. There are more species like tantalum, mylar, silver mica, ...
They all do the same work, but some just sound better in audio circuits like guitar stompboxes.

I took a look at the schematic and it clearly states that u needed to use a electrolytic cap ("elko" for short). You can see it has a slightly different symbol, one legg is a bit rounder than the other one.

I can't really predict the effect of a wrong cap here because I've never made that fault myself. But mostly there is a reason for using elko's, like decoupling caps for blocking dc voltage...
Maybe you need to read some more about capacitors Here.
If you're not used to the units, you can use this chart to convert them, it's a pretty handy page.

petemoore

I just noticed that the ONE thing that I have in my parts that is incorrect is the 0.01uF capacitor is NOT polarized.

So, is it really important for the capacitor to be polarized?

  Non polarized caps don't recognize polarity...
 
 
Convention creates following, following creates convention.

billings

As far as I know, the main difference between a polar electrolytic capacitor and a non-polar capacitor (electrolytic or no) is that a polar electrolytic cap will explode if you hook it up wrong or in an inappropriate place in a circuit.  I used non-polar (bi-polar?) electrolytics in my fuzz face build and had no problem at all.  If anything, they give you less things to screw up.  The polar ones are cheaper, though, and provide identical performance.

petemoore

  at about 1uf, maybe a little more, non-polarized caps start becoming less available, I don't know what the largest avaialble value is, but electolytics are available in values of 4u7, I don't remember hearing of a 2u2 NP.
  Overvoltaging a cap rating damages the cap.
  Reverse polarizing a polarized cap damages the cap.
Convention creates following, following creates convention.

daren

Sorry. I didn't right out my question correctly. The odd store clerk didn't believe that there are polarized capacitors at such as small charge (0.01uF). I'll just bug him tomorrow about it.

The capacitor I tried using for the 0.01uF capacitor is a ceramic one, I don't know if that will prevent anything from going through, but I sure hope so, because then I can finally finish my first pedal.