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Old 2nd May 2011, 03:52 PM   #31
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Quote:
Originally Posted by komigenie View Post
hmm, whats the value of this Capacitors on this red board ? 220/35 or something diferent .. i see ther 47/50 ...

what should be best value and what kind of cap ?
The caps on the red Jim's Audio PCBs are 47 mfd, 50 vdc. They are non-critical, and are in fact optional in the design. The Pass design does not use them.
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Old 2nd May 2011, 11:55 PM   #32
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then i'll plan on getting a proper trafo, and should i wait until i get it together and running, to try anymore playing with the amplifiers?
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Old 3rd May 2011, 06:59 PM   #33
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It looks like the N channel irfp240 is gone - as you indicated the offset is -27V.
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Old 3rd May 2011, 10:22 PM   #34
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i'm going to get the right transformer, and i'll have to get back to this once i caqn get it going, to see if my voltages being too high is the issue
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Old 4th May 2011, 04:14 AM   #35
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Quote:
Originally Posted by CanAm Man View Post
The caps on the red Jim's Audio PCBs are 47 mfd, 50 vdc. They are non-critical, and are in fact optional in the design. The Pass design does not use them.
I presume that they tie to ground, otherwise oscillation is a real possibility.

If in doubt, try taking them out.

More poetry:

When Q4 goes
R14 blows

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Old 4th May 2011, 05:59 AM   #36
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yes, they do tie to ground.

as well as in that case! i'll be replacing Q4!
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Old 5th May 2011, 12:03 AM   #37
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Quote:
Originally Posted by Nelson Pass View Post
I presume that they tie to ground, otherwise oscillation is a real possibility.

If in doubt, try taking them out.

More poetry:

When Q4 goes
R14 blows

so if you dont mind me asking, if Q4 goes out, do i just have current flowing strait through it to R14? is that whats happening?
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