1uf Non-Polar Tantalum Capacitors - replacement for expensive films?

Started by chromesphere, June 04, 2013, 01:22:08 AM

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chromesphere

Hi everyone,
In my recent build report (Youtube channel) for the 'prismatic reverb' aka dead astronaut flying saucer reverb i mentioned that i used a tantalum in place of a film cap for a 1uf capacitor as i didnt have any 1uf films on hand.  These were 12c each.  Haveyouseenhim (mike) on this forum suggested it is a multi layer ceramic but i dont believe it is.  There is a seperate section on the Tayda site for those.  This one DEFINITELY came from the tantalum section.

So the questions.
1) as it's not popalrised does that mean its a non-polar tantalum?  I know you can get NP tants.  But would this be one? Or something else entirely!?
2) it was cheap 12c.  Can we use these instead of 1uf films that can cost 2x or 3x more.  And can you use them in any application?  I had no trouble with in my reverb.

Im fairly certain its just a NP tant, and im fairly certain you could use it whereever without problems, but i thought i would ask the experts.  Heres a link to the cap:

http://www.taydaelectronics.com/capacitors/tantalum-capacitors/1uf-50v-radial-tantalum-capacitor.html

Cheers,
Paul
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Pedal Parts Shop                Youtube

psychedelicfish

My suggestion is:
Buy a whole load of them. Get a 60V (or more) power supply. Hook them up directly across it (outside). Stand back, and if they explode violently, they're tantalums. If they have some kind of polarity marking on them (even just one lead longer than the other) hook one up to the power supply with what you think is the positive side to the positive end of the supply, and the negative to the negative. Time how long it takes for it to explode, and record the data, along with the polarity. Do the same, but with the opposite polarity. Record the time and polarity. Repeat a few more times until you have some reliable data.
;D
If at first you don't succeed... use bigger transistors!

chromesphere

There is no marking on the capacitor and no lead length difference.

So these CAN NOT be non polar tantalums?  They HAVE TO BE tantalums?  and i LOVE TO USE caps lock?

Edit, Haveyouseenhim just pointed out the lead lenght in the photos on tayda, hah!  Maybe i just didnt notice when i solder it in.

Anyway, onto question 2:

Can you use a 1uf tantalum willy nilly in place of a 1uf film cap?

Edit again: Ahhh!  There was a recent thread about cap polarity.  I remember the advise was bascially dont use them in the signal path because the polarity is not straight forward, plus or minus.

Paul
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Pedal Parts Shop                Youtube

armdnrdy

I've ordered and installed the tantalum capacitors from Tayda and they are definitely polarized.

If you look closely, you'll see that one lead is longer than the other and on that side of the cap there is a + sign indicating......positive.

Tayda doesn't stock any non polarized caps except for ceramic, poly box type, poly "greenies,"  and a small amount of multi layer ceramics.

I wish they at least stocked 1µf non polar electrolytics!

Edit:
Looks like Paul posted as I was writing.
One other scenario is that you ordered  tants and they sent you multi layers.
I ordered (3) 2PDT footswitches and they sent (3) green knobs! They came in a bag with the proper switch part number sticker on it.
I just designed a new fuzz circuit! It almost sounds a little different than the last fifty fuzz circuits I designed! ;)

chromesphere

Quote from: armdnrdy on June 04, 2013, 01:53:21 AM
I've ordered and installed the tantalum capacitors from Tayda and they are definitely polarized.

If you look closely, you'll see that one lead is longer than the other and on that side of the cap there is a + sign indicating......positive.

Tayda doesn't stock any non polarized caps except for ceramic, poly box type, poly "greenies,"  and a small amount of multi layer ceramics.

I wish they at least stocked 1µf non polar electrolytics!

Ill have to double check but im SURE i didnt see a + sign...then again I didnt notice the freaking lead size difference either so anythings possible at this point....ill check them out tonight.

Paul
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Pedal Parts Shop                Youtube

Rethfing

The cap you posted link about is different than the one you show in your latest video. This one in the video is actually tantalum, but the one in video is ceramic KCM.

chromesphere

Ok so heres a photo of the cap.

I looked up A-321 and it looks like its a monolithic!!  pretty sure I ordered a tant....oh well, case closed.




SO.  Do you guys use <MONOLITHIC> caps in place of 1uf films?   Anything to be concerned of?  Harsh tone?  Insult to the tone gods?

Paul
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Pedal Parts Shop                Youtube

IvIark

These are good, cheap and non-polar alternatives to 1u film caps, I use these quite a lot where the film cap would be physically too large to fit comfortably in the space:
http://www.ebay.co.uk/itm/250879684670

Rethfing

I also used them couple of times and heard no difference. I even used normal polarized electrolytic cap in place of those and the pedals still worked fine. I heard a statement once on this forum: "Caps are caps", and I stick to it :D

chromesphere

Quote from: Rethfing on June 04, 2013, 03:39:11 AM
The cap you posted link about is different than the one you show in your latest video. This one in the video is actually tantalum, but the one in video is ceramic KCM.

Yep, its confirmed!  Hah, there you go!  

Checked the order, apparently that's what I ordered!  

What a mess up...sorry everyone for the confusion.

Paul
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Pedal Parts Shop                Youtube

armdnrdy

I just designed a new fuzz circuit! It almost sounds a little different than the last fifty fuzz circuits I designed! ;)

R.G.

I'd never seen NP tantalum, so I went off looking. Didn't find any. I'm sure it's possible.

I also checked prices. Mouser wants US$0.39 for a 1uF 35V tantalum and... yep, $0.39 for a 1uF/63V film cap. 1uF/25-50V ceramic in epoxy dipped radial is $0.15-$0.45 in ones.

The surface mount parts are significantly cheaper for tantalum and ceramic.
R.G.

In response to the questions in the forum - PCB Layout for Musical Effects is available from The Book Patch. Search "PCB Layout" and it ought to appear.

armdnrdy

Quote from: R.G. on June 04, 2013, 08:28:56 PM
I'd never seen NP tantalum, so I went off looking. Didn't find any. I'm sure it's possible.

Google first try:
http://www.vishay.com/docs/49054/49054_sg2160.pdf

Look though the PDF, there are several different part numbers that are available in polar or non polar.
I just designed a new fuzz circuit! It almost sounds a little different than the last fifty fuzz circuits I designed! ;)

Jdansti

  • SUPPORTER
R.G. Keene: EXPECT there to be errors, and defeat them...

armdnrdy

Those are very nice caps John....but now you have posted partial finger prints on the internet!

A crafty individual can now make replicas of your prints....leave those prints at the scene of a crime to implicate someone else!

Guess who that someone else is??????


Do you know a good criminal attorney?  :o
I just designed a new fuzz circuit! It almost sounds a little different than the last fifty fuzz circuits I designed! ;)

Jdansti

^ I tend to look at it the other way 'round. Now I can commit crimes and blame it on some guy on DIYSB who replicated and planted my fingerprints!   :P
  • SUPPORTER
R.G. Keene: EXPECT there to be errors, and defeat them...

chromesphere

OK John, what if I use your finger prints to break into your house and steal your caps?  That's going to be difficult to explain to the cops hah?

;-)
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armdnrdy

Quote from: chromesphere on June 05, 2013, 03:44:19 AM
OK John, what if I use your finger prints to break into your house and steal your caps?  That's going to be difficult to explain to the cops hah?

;-)

Especially since John lives in Texas and you live in Australia! 
No one in their right mind would ever believe that someone would pay for the airfare from Australia to Texas and break into a house to steal $2.00 worth of capacitors!

Although stranger things have happened!  :icon_lol:
I just designed a new fuzz circuit! It almost sounds a little different than the last fifty fuzz circuits I designed! ;)

chromesphere

Well I ordered monolithics without realising so yeah, I'm a Crazy Aussie :D
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Pedal Parts Shop                Youtube

Jdansti

Let me know when you plan to break into my house and I'll make sure that my wife isn't home at the time. We would miss you on the forum!   :icon_cry:
  • SUPPORTER
R.G. Keene: EXPECT there to be errors, and defeat them...