I have no cabinet sound on my DE SW. Left and right sound works fine. Here's the run down:
-Sound board version 520-5050-00 Rev. C
-I have continuity from the sound board to the speaker so the wiring is good
-The speaker is good
-Voltages to the sound board check fine. If anything, the +12v is high (14.11). 5v is 4.94.
-On the MB3730A amplifier for the cabinet sound I get 10.9v at pin 7 (VCC) with respect to ground, this is the same as the other two MB3730A amplifiers for the left-right sound.
-On pins 5 and 6 (the output of the MB3730A for the cabinet sound), I get 10.42v with respect to ground. On the other MB3730A for LR sound I get 4.65v. So this obviously a lot higher.
-On the +/- speaker outs for the LR sound, I can measure AC voltage between the the connections (obviously or there would be no sound). On the +/- out of the cabinet sound I measure no AC voltage between the connections.
-The MB3730A amplifier for the cabinet sound gets noticeably hotter than the other two amplifiers.
Any suggestions on where to go next? Any other measurements I should take? Should I replace the MB3730A amplifier? They are $7.50 at GPE. Check and replace capacitors?
Thanks!
-Sound board version 520-5050-00 Rev. C
-I have continuity from the sound board to the speaker so the wiring is good
-The speaker is good
-Voltages to the sound board check fine. If anything, the +12v is high (14.11). 5v is 4.94.
-On the MB3730A amplifier for the cabinet sound I get 10.9v at pin 7 (VCC) with respect to ground, this is the same as the other two MB3730A amplifiers for the left-right sound.
-On pins 5 and 6 (the output of the MB3730A for the cabinet sound), I get 10.42v with respect to ground. On the other MB3730A for LR sound I get 4.65v. So this obviously a lot higher.
-On the +/- speaker outs for the LR sound, I can measure AC voltage between the the connections (obviously or there would be no sound). On the +/- out of the cabinet sound I measure no AC voltage between the connections.
-The MB3730A amplifier for the cabinet sound gets noticeably hotter than the other two amplifiers.
Any suggestions on where to go next? Any other measurements I should take? Should I replace the MB3730A amplifier? They are $7.50 at GPE. Check and replace capacitors?
Thanks!