[LAU] Audio interface for newbies ?

[Ralf Mardorf]

On Fri, 26 Aug 2016 20:08:54 -0700 (PDT), Len Ovens wrote:
>On Sat, 27 Aug 2016, Ralf Mardorf wrote:
>
>> On Fri, 26 Aug 2016 17:51:25 -0400, jonetsu at teksavvy.com wrote:  
>>> On Fri, 26 Aug 2016 22:50:27 +0200 Ralf Mardorf wrote:  
>>>> Why isn't it happening all the times, if the capacitors are dried
>>>> out?  
>>> There would be a transition time I think.  
>>
>> This could be possible.
>>
>> If they are dried out, then capacitance got lost. If the the oxide
>> coating is broken, they short.
>>
>> What is a capacitor used for, that could cause delayed trouble, if
>> it's broken, instead of causing the trouble all the times?
>>
>> IIUC you hear the crackling only, if there is an audio signal,
>> there's no crackling, without an audio signal.  
>
>This page indicates that the power supply caps.... well the whole
>power supply, is less than adequate already.

Again guessing. This card is not an amplifier that requires a big
reliable power supply, neither it's comparable to a CRT, that has got a
high power consumption.

I do not own this card, so I ask questions to perhaps provide more than
just guessing. I didn't find a circuit layout, but already tried to
read on a photo what is printed on the large TO-220 package component.

I didn't find a photo where I could read what's printed on it, but
while searching such a photo, I found this

https://offog.org/notes/delta-1010lt-repair/

So the two capacitors close to the large TO-220 package component are
reservoir capacitors. Note, my PCI Envy24 cards have a voltage
regulator were the delta seems to have one, too. At the further end of
the large TO-220 package component, there are two small capacitors and
something that looks like a miniature edition of a TO-220 package. On my
cards it's a 1117 voltage regulator.

However, assuming that the provided power by the computer's power
supply should be too fluctuating, to feat the stabilisation of the
delta, I would suspect more dramatic effects. If the stabilisation
should be the reason for the issue, then I would expect broken
capacitors on the audio card.

Regards,
Ralf