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#1,123
I would like to post a small revision for the tube section I proposed on this thread.
I added two resistors to charge and discharge the output capacitors safely.
I omited them because I only build things for myself and these resistors where already present in my setup.

So the need to be as general as possible when you share ideas with others.

Jean-Charles
 

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#1,127
Hi,

More here
http://www.diyaudio.com/forums/showthread.php?s=&postid=997741#post997741

But to sum up, i tried ASUS DVD-ROM Drive (E616) and ASUS CD-RW + Plextor DVD-ROM P130A + Nec DVD-RW ( i don't have the reference) They all work. Just in case, i have the message you wrote when the drive was not in master mode.

If anyone has tips about Asus DVD-ROM E616 reclocking (where to find the Crystal and which frequencies) i'm interested.

RTD,
 
#1,132
Tube-lover (Thomas) is On Leave Again

Dear all,

I would like to inform you that my friend Tube-lover (Thomas) has been re-admitted to the hospital again owing to the inflammation of his leg after surgery.

He cannot respond to any enquiries for some days until he returns.

Regards,
T.C. MA
25 Sep. 2006
 
#1,135
hi all,

first, get well too thomas !

second a little question, Thomas here sugested using 0.1 uF MKP (Wima or EPcos...) for the coupling cap after the opamp . If we consider the polarized existing cap (ex: C85,C90) they are equivalent to approximatively to 22 uF.
So ok for replacing them with a 0.1 uF MKP, but is this the best value ?
Could it be better to use for instance 1 uF MKP ( if cap size is not a problem) ? Are the opamp + R + coupling Caps a low pass filter or the opposite ?

thanks if some has ideas,
 
#1,137
rtd said:
hi all,

first, get well too thomas !

second a little question, Thomas here sugested using 0.1 uF MKP (Wima or EPcos...) for the coupling cap after the opamp . If we consider the polarized existing cap (ex: C85,C90) they are equivalent to approximatively to 22 uF.
So ok for replacing them with a 0.1 uF MKP, but is this the best value ?
Could it be better to use for instance 1 uF MKP ( if cap size is not a problem) ? Are the opamp + R + coupling Caps a low pass filter or the opposite ?

thanks if some has ideas,
Click to expand...

To answer myself 😉, there is a 47k resistor before output, so the cut frequencies should be around 33Hz with this 47k and coupling caps of 0.1uF, with 0.22uF we should have 15 Hz, so is this right ???
 
#1,140
rtd said:
hi all,

first, get well too thomas !

second a little question, Thomas here sugested using 0.1 uF MKP (Wima or EPcos...) for the coupling cap after the opamp . If we consider the polarized existing cap (ex: C85,C90) they are equivalent to approximatively to 22 uF.
So ok for replacing them with a 0.1 uF MKP, but is this the best value ?
Could it be better to use for instance 1 uF MKP ( if cap size is not a problem) ? Are the opamp + R + coupling Caps a low pass filter or the opposite ?

thanks if some has ideas,
Click to expand...


rtd said:


To answer myself 😉, there is a 47k resistor before output, so the cut frequencies should be around 33Hz with this 47k and coupling caps of 0.1uF, with 0.22uF we should have 15 Hz, so is this right ???
Click to expand...


:xeye: I made a mistake (C85,C90) is equivalent to 11 UF. And I think 0.22 uF is even too low if u by instance use a preamp with an impedance of 10 ko
 
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