output transformers

[Dmoney]

can changing OT stop the presence control in my amp from working?
i took out the depth mod in my jcm800 and return it to stock, purple wire from R47 to the 4ohm lug.
still nothing.

not sure what to check next...
try in the cable on the 8 or 16 ohm tap?

[nilsampmaker]

Took a quick check at some schematics and couldnīt find a R47, but the wire should go from the opt to a 100k resistor (R22) that in turn is connected to the presence pot and a resistor and capacitor. Referred to this schematic http://www.dreamtone.org/pdf/NEW2204LayoutSchemBomDreamTone.pdf. Cheers