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previous: JohnC I just got an Orange Overdrive Seri... -- 6/21/1999 0:54 AM

Re: Orange help, svp

6/21/1999 3:02 AM
D.L.	Re: Orange help, svp Has the amp 2 or 4 output tubes ? Do you have any experience with methods of working on hi voltage equipment? You should familiarize yourself with the routine of unplugging the amp, draining the residual voltages out of the amp with an insulated clip lead, one end clipped to chassis ground other end touched firmly to each plate connection or B+ or to the filter cap+ terminals themselves whenever you are gonna be hanging around an open chassis. I have a schem for Orange but dont have my scanner working right now. You have one trim pot for the hum balance of the heater supply on the preamp tubes and one for the neg bias voltage on the power tubes- they call for minus 37 volts d.c. on the grids of the power tubes. Your neg meter probe will go to the grid (pin 5) your pos probe on the meter goes to ground (chassis) USE an alligator clip to attach your meter probe to the tube socket lug AFTER you have unplugged the amp and drained the charge off the main filter capacitors, then put one hand in your back pocket, use your free hand to touch the pos probe to chassis. gotta run, good luck.

6/21/1999 3:02 AM

D.L.

Re: Orange help, svp

Has the amp 2 or 4 output tubes ? Do you have any experience with methods of working on hi voltage equipment?

You should familiarize yourself with the routine of unplugging the amp, draining the residual voltages out of the amp with an insulated clip lead, one end clipped to chassis ground other end touched firmly to each plate connection or B+ or to the filter cap+ terminals themselves whenever you are gonna be hanging around an open chassis.

I have a schem for Orange but dont have my scanner working right now. You have one trim pot for the hum balance of the heater supply on the preamp tubes and one for the neg bias voltage on the power tubes- they call for minus 37 volts d.c. on the grids of the power tubes. Your neg meter probe will go to the grid (pin 5) your pos probe on the meter goes to ground (chassis) USE an alligator clip to attach your meter probe to the tube socket lug AFTER you have unplugged the amp and drained the charge off the main filter capacitors, then put one hand in your back pocket, use your free hand to touch the pos probe to chassis.

gotta run, good luck.

Replies:

JohnC >Has the amp 2 or 4 output tubes ?<... -- 6/21/1999 11:51 PM