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VTA M-125 mono block kit.
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Old 9th January 2017, 09:19 PM   #21
boatheelmusic is offline boatheelmusic  United States
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Actually, it's star grounded.
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Old 9th January 2017, 09:20 PM   #22
boatheelmusic is offline boatheelmusic  United States
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Try running the yellow negative feedback wire right up the chassis to the board instead of along the side.
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Old 9th January 2017, 10:11 PM   #23
dahlberg is offline dahlberg  Sweden
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Quote:
Originally Posted by boatheelmusic View Post
Try running the yellow negative feedback wire right up the chassis to the board instead of along the side.
Well the yellow wire isn't yellow any longer, it's black and it's screened. It
helped a bit but not all the way. It changed position a bit as well during that
change. I have some consern about filament wiring from the transformer to
the output tubes. Also pentode/UL wiring is drawn between the output tubes
instead of along the side of the input pcb. The signal wire is also changed for a
screened one, dual wire, screen connected at the pcb ground (not in the picture).
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Old 9th January 2017, 10:14 PM   #24
boatheelmusic is offline boatheelmusic  United States
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Be very sure all those screens terminate at the star grounding lugs.
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Old 9th January 2017, 10:18 PM   #25
Bob01605 is offline Bob01605  United States
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Quote:
Originally Posted by boatheelmusic View Post
Try running the yellow negative feedback wire right up the chassis to the board instead of along the side.
The second photo shown in post #18 is not the correct photo of the CCS version of the M-125 amp. That photo in post # 18 may still be online. I will track it down and have it removed. The correct photo for the CCS version of the M-125 is shown below. Yes - As Boatheelmusic has mentioned > You are advised to run the yellow wire that goes to the NFB eyelet on the driver board away from the two wires that connect to the input jack. You should run the wire as shown in the photo below.

Bob Latino

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Old 9th January 2017, 10:45 PM   #26
dahlberg is offline dahlberg  Sweden
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Quote:
Originally Posted by Bob01605 View Post
The second photo shown in post #18 is not the correct photo of the CCS version of the M-125 amp. That photo in post # 18 may still be online. I will track it down and have it removed. The correct photo for the CCS version of the M-125 is shown below. Yes - As Boatheelmusic has mentioned > You are advised to run the yellow wire that goes to the NFB eyelet on the driver board away from the two wires that connect to the input jack. You should run the wire as shown in the photo below.

Bob Latino

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Thanks Bob. I will try to relocate the feedback wire tomorrow, how about my filament wiring ?
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Old 9th January 2017, 10:49 PM   #27
Bob01605 is offline Bob01605  United States
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The filament wiring looks fine .. well done ..

Bob
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Old 9th January 2017, 10:56 PM   #28
dahlberg is offline dahlberg  Sweden
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Quote:
Originally Posted by Bob01605 View Post
The filament wiring looks fine .. well done ..

Bob
Thanks.
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Old 9th January 2017, 11:10 PM   #29
BinaryMike is offline BinaryMike  United States
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Quote:
Originally Posted by boatheelmusic View Post
Actually, it's star grounded.
I'm seeing at least three chassis ground connections, two at the cathode resistors and one at the multi-section 'lytic.
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Old 10th January 2017, 12:12 AM   #30
dahlberg is offline dahlberg  Sweden
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Quote:
Originally Posted by boatheelmusic View Post
Be very sure all those screens terminate at the star grounding lugs.
The pcb is already connected there, why would it be a better idea to connect the
screens with an additional wire to the star ground point ?
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