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Old 12th December 2011, 03:21 PM   #1401
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@Limp, did you run all the power controller tests in the Initial DIY Testing section? You might have static zapped a MOSFET and one of them is stuck on which would cause one rail to turn on before the other making for a much bigger transient. With either rail low, both MOSFETs should shut off. Be sure and conduct the tests with no headphones connected.
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Old 12th December 2011, 03:57 PM   #1402
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Default Remote mounting pot

I'm planning on running this using the batteries for most of the time. Puting the battery on the board, the wires are pretty much right on top of the batteries, may be 1mm over it. Is that ok? or will the batteries introduce noise into the pot cables?
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Old 12th December 2011, 04:18 PM   #1403
Limp is offline Limp  Norway
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I'm getting 24V across C8 and C9.
Bugger, I guess that means being careful with those MOSFETs just isn't careful enough.

Last edited by Limp; 12th December 2011 at 04:22 PM.
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Old 12th December 2011, 06:30 PM   #1404
Limp is offline Limp  Norway
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Quote:
Originally Posted by RocketScientist View Post
@Limp, did you run all the power controller tests in the Initial DIY Testing section? You might have static zapped a MOSFET and one of them is stuck on which would cause one rail to turn on before the other making for a much bigger transient. With either rail low, both MOSFETs should shut off. Be sure and conduct the tests with no headphones connected.
Everything seems fine, right up to the Low Voltage Shutdown test. With one battery intalled I get ~.5V, and with the other I get about half that. Now both are below the .7V you mention in the blog, but it is still a prety large discrepancy.
Is this where the problem is?
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Old 12th December 2011, 07:10 PM   #1405
qusp is offline qusp  Australia
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Quote:
Originally Posted by hbarradah View Post
I'm planning on running this using the batteries for most of the time. Puting the battery on the board, the wires are pretty much right on top of the batteries, may be 1mm over it. Is that ok? or will the batteries introduce noise into the pot cables?
unlikely, its DC, it doesnt introduce much EMI like transformers (AC) do.
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Old 12th December 2011, 08:39 PM   #1406
Alexium is offline Alexium  Ukraine
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Originally Posted by RocketScientist View Post
FIY, "decoupling capacitors" are used on power supply lines to decouple power supply noise from other components and present a low power supply impedance to components.
Thank you very much for taking time to reply and educate me (I'm just starting to understand electronics).
I feel severe lack of electrical engineering vocabulary. In Russian C13 and C14 would be called "decoupling" or "separating" caps as they decouple signal from DC component, and C17/C18 would be just called "filtering" caps.
Is there any site or book which could help me to quickly learn most common English terms of electrical engineering domain?

P. S.
Limp, thanks for the refernce photo!

Last edited by Alexium; 12th December 2011 at 09:04 PM.
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Old 12th December 2011, 09:27 PM   #1407
oslpag is offline oslpag  Sweden
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Default Transformer

I am having a nightmare trying to find a power supplier for the O2 here in the UK. I have found this, would it work for the UK?
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Old 12th December 2011, 09:35 PM   #1408
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unlikely, its DC, it doesnt introduce much EMI like transformers (AC) do.
cool, thanks qusp.
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Old 12th December 2011, 10:35 PM   #1409
agdr is offline agdr  United States
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Originally Posted by oslpag View Post
I am having a nightmare trying to find a power supplier for the O2 here in the UK. I have found this, would it work for the UK?
It will if the plug fits properly in the O2. The output ratings are fine. 16VAC 700mA puts it right between the WAU16-400 and WAU16-1000 adapters on the BOM in terms of current capability, but the manufacturer doesn't specify if the output plug is a 2.1mm.

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If you have access to the adaptor just try it to see if it fits, otherwise maybe the seller could confirm what output plug it has.
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Old 12th December 2011, 10:39 PM   #1410
oslpag is offline oslpag  Sweden
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Originally Posted by agdr View Post
It will if the plug fits properly in the O2. The output ratings are fine. 16VAC 700mA puts it right between the WAU16-400 and WAU16-1000 adapters on the BOM in terms of current capability, but the manufacturer doesn't specify if the output plug is a 2.1mm.

Sandan Limited (BS)

If you have access to the adaptor just try it to see if it fits, otherwise maybe the seller could confirm what output plug it has.
Thanks for the info. I am not too worried about the output plug, that can easily be sorted out. I will get one and see how it goes as it is not so expensive.

Thanks again
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