VT-150 Schematic or Service Manual

[spippolone]

Hi my friends,
I have a VT-150 with low bias.. I excange the tubes with other channel but the same amplifier has a low bias.
I can turn all clockwise the adjust pot, but the maximum value are 40 mA
Someone know this problem ? I have found the schematic of VT-150SE but I don't think that it is the same.. Someone can help me ?

Thank you in advance

 

[baudouin0]

Cannot find VT150 but some similar schematics here which may help:
http://4tubes.com/2-SCHEMATICS/BY-BRAND/Audio-research/

 

[baudouin0]

The VT150 and VT150SE are the same manual - so I guess the SE has more monitoring.
https://arcdb.ws/Database/VT150/ARC_VT150SE_schematic_and_parts_list.pdf

 

[spippolone]

Thank you for your interest... now I try to check it ..

 

[OldHector]

Seems so complicated - does the design warrant all of those ICs?

 

[spippolone]

Good morning .. fortunately .. the problem is the alignment and the variation of the characteristics over time .. with a precise and delicate adjustment of the currents I solved the problem.