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Old 9th February 2013, 08:19 PM   #3111
ericj is offline ericj  United States
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Quote:
Originally Posted by DevilsRightHand View Post
All the parts were in the same bag, so I had to check the values of each resistors, which is easy, but now I have 8 ceramic caps that I can't figure their values. Here's what I have:

4x with BC 221 on it
2x with BC 105z
1x 223 E1M
1x 213AFP

That's what is writen on them an I don't know what it means
Why not compare the numbers on the parts with the values in the bill of materials?

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Old 9th February 2013, 09:09 PM   #3112
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Those number codes signify picofarads. 1st digit, 2nd digit, tens multiplier. So...
221 = 220pF (C11, C12, C19, C20)
105 = 1000000pF = 1μF (C1)
223 = 22000pF = 0.022μF
213 = 21000pF = 0.021μF
The last two are for C16 & C21. Probably an availability issue, so a cap 1 nanofarad less was substituted. Virtually no difference where it's used in the O2 power management circuit.
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Old 11th February 2013, 02:41 PM   #3113
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I had difficulty with those capacitors, too, but I guess I got them right. Mine were also different than what they were in O2 reference pictures. Capacitor calculator really helped with them.

Anyway, my subject was that I just plugged my O2 to a DC adapter and now it outputs no sound anymore. It still "works" with one battery though, but clips very badly.

Where could I get some spare parts for the O2 in EU? Also do you know which parts could potentially be broken with it?
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Old 11th February 2013, 03:24 PM   #3114
ericj is offline ericj  United States
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Quote:
Originally Posted by hedphones View Post
I had difficulty with those capacitors, too, but I guess I got them right. Mine were also different than what they were in O2 reference pictures. Capacitor calculator really helped with them.

Anyway, my subject was that I just plugged my O2 to a DC adapter and now it outputs no sound anymore. It still "works" with one battery though, but clips very badly.

Where could I get some spare parts for the O2 in EU? Also do you know which parts could potentially be broken with it?
If you go back a couple pages, when I did that it cooked the 4556 chips. It sounds like you are down a battery too? Make sure you replace the damaged one with the exact same, or just replace both.

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Old 11th February 2013, 06:52 PM   #3115
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I just got done soldering the O2 and I have to say that I am quite impressed. However, I have some opamps from previous projects such as the LM4562, AD8066, AD8620, etc. If I were to try these out in the O2 build, which slot do I switch them into? U1, U2, U3, U4? Thanks!
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Old 11th February 2013, 08:05 PM   #3116
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Originally Posted by defi View Post
I just got done soldering the O2 and I have to say that I am quite impressed. However, I have some opamps from previous projects such as the LM4562, AD8066, AD8620, etc. If I were to try these out in the O2 build, which slot do I switch them into? U1, U2, U3, U4? Thanks!
4562 and 8620 may replace the 2068 effectively. 8066 may be too fast of a chip for this board. Or not.

Give the stock parts a few hours burnin and you will be even more impressed. And i do mean few.



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Old 12th February 2013, 04:01 AM   #3117
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Quote:
Originally Posted by gootee View Post
....There's bypassing and there's decoupling....
Good explanation, I will be reading more on "Power Supply Resevoir Size" .
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Old 12th February 2013, 04:15 AM   #3118
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Quote:
Originally Posted by hedphones View Post
...Anyway, my subject was that I just plugged my O2 to a DC adapter and now it outputs no sound anymore. It still "works" with one battery though, but clips very badly....
For spares take help from swalter of "head n' hifi".

BTW What really happens if you connect DC adapter? Does the o/p is busted if h/p is connected apart from 1 bat. not getting charged? Or does the PM of O2 offers some protection from DC adapter.?
I wont be doing this trial/mistake on my O2
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Last edited by availlyrics; 12th February 2013 at 04:22 AM.
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Old 12th February 2013, 01:28 PM   #3119
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Originally Posted by ericj View Post
If you go back a couple pages, when I did that it cooked the 4556 chips. It sounds like you are down a battery too? Make sure you replace the damaged one with the exact same, or just replace both.

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I measured my batteries, they were about 8.8V each. Anyway weird thing, yeasterday my O2 worked for few minutes fine, but then as I turned power on and off, it stopped working again.. I'll take some measurements and post here later..
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Old 12th February 2013, 04:45 PM   #3120
swalter is offline swalter  Switzerland
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Quote:
Originally Posted by sofaspud View Post
[...]
223 = 22000pF = 0.022μF
213 = 21000pF = 0.021μF
The last two are for C16 & C21. Probably an availability issue, so a cap 1 nanofarad less was substituted. [...]
Hi, finally found some time to read up on the thread.

I guess the set came from me, just to point out that the caps are actually packed like this from mousers supplier, I just take two out of a bag of a thousand and do not really read what is printed on them when preparing the kits.
Taking the tolerance of 20% into account those caps have, even a 173 would still be within specs as long as it has a tiny bit of positive tolerance

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