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previous: Toddy Hi,I'm wondering if anyone know... -- 5/22/2003 12:06 AM

Re: Bassman CFA7100 schematic and dilemma

5/22/2003 7:25 AM
Enzo	Re: Bassman CFA7100 schematic and dilemma CFA7100? Hum balance is easy to add, or do it the lazy way like they did on many models - run a 100 ohm resistor from either side of the filament line to ground. They usually did this on the rear of the power light socket, check there to see if they are already installed. But first make sure the heater winding is not center tapped with the tap grounded. If you replaced a bunch of caps and NOW it blows fuses, check your work. Chances are one of them is in backwards, or you left a lead where it can touch chassis, or you mis-wired. The value of the cap is irrelevant. Too small a cap results in more hum, that is all. Mod in some bias resistors. Do you mean you want to install 1 ohm resistors to measure cathode current? or do you want to change the values of existing resistors for some purpose? If the former, just wire them between pin 8 and ground on the output tube sockets. Remove the wire that grounds pin 8.

5/22/2003 7:25 AM

Enzo

Re: Bassman CFA7100 schematic and dilemma

CFA7100?

Hum balance is easy to add, or do it the lazy way like they did on many models - run a 100 ohm resistor from either side of the filament line to ground. They usually did this on the rear of the power light socket, check there to see if they are already installed. But first make sure the heater winding is not center tapped with the tap grounded.

If you replaced a bunch of caps and NOW it blows fuses, check your work. Chances are one of them is in backwards, or you left a lead where it can touch chassis, or you mis-wired. The value of the cap is irrelevant. Too small a cap results in more hum, that is all.

Mod in some bias resistors. Do you mean you want to install 1 ohm resistors to measure cathode current? or do you want to change the values of existing resistors for some purpose? If the former, just wire them between pin 8 and ground on the output tube sockets. Remove the wire that grounds pin 8.

Replies:

Toddy Thanks Enzo for the speedy reply!!<... -- 5/22/2003 9:29 AM