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power selection switch, question/ choice.

4/14/2000 4:58 AM
Bryan James	power selection switch, question/ choice. was looking at the marshall jcm900 schematic and noticed a switch that changes the input on the screen of the el34 from just after to the choke to in parrellel with the plate. the switch is labeled hi low. is this the half output power switch? can someone explain how it works? and which would be better to put in a output section. (built from scratch, not moding) this high low switch or the 60/100 switch from mesa/boogie (the one that removes 2 of the tubes from ground. -Bryan

4/14/2000 4:58 AM

Bryan James

power selection switch, question/ choice.

was looking at the marshall jcm900 schematic and noticed a switch that changes the input on the screen of the el34 from just after to the choke to in parrellel with the plate. the switch is labeled hi low.
is this the half output power switch?
can someone explain how it works?
and which would be better to put in a output section. (built from scratch, not moding) this high low switch or the 60/100 switch from mesa/boogie (the one that removes 2 of the tubes from ground.

-Bryan

Replies:

DIRTY L KARLSSON It´s a pentode/triode switch. -- 4/14/2000 5:13 AM
dale as the last guy said, it's a pentod... -- 4/15/2000 1:40 AM