Please help me with this complicated beast. I have power to all other tubes. I checked the tubes. They are good. I also don't have any front panel lights. I found a schematic on here but this thing is going to be really difficult to trace. Is this a common problem with these amps? Where should I start? Please help me avoid sending this thing to Cali. Thanks in advance!
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Need help with my Mesa Mark V. No power on V1, V2 & V5
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That link is to the file on your hard drive - no good here. Click Go Advanced below, then Manage Attachments, then navigate to the file, click Add Files, and navigate to the file.
I suspect that unlike the rest, those three tubes are fed by a 12VDC filament supply, giving you 6VDC across each heater. If so, there will be a TO220 regulator IC somewhere on the chassis.
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On pg.1 of the schematic, there is a LM2940 regulator powering the heaters of V1, V2, and V5.Attached FilesOriginally posted by EnzoI have a sign in my shop that says, "Never think up reasons not to check something."
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Originally posted by Redline View PostWeird... I can't find that one. I found an LM780. That's all."I took a photo of my ohm meter... It didn't help." Enzo 8/20/22
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Originally posted by Redline View PostWeird... I can't find that one. I found an LM780. That's all.
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Originally posted by Orbeck View PostToo hard for me, even if I am trying to follow all the steps.
Here is the pinout, what DC voltages do you measure at pin 1 and pin 3?
Originally posted by EnzoI have a sign in my shop that says, "Never think up reasons not to check something."
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