Silvas
Well-known member
Hi!
I´ve been playing with the fetboy circuit for a while and love it. I´m getting about 7.2 volts on the output (unbalanced and transformerless) before the output begin to clip. i sticked to the original 47k resistor value as higer values clipped one side of the waveform too early. Less than 42k is playing with fire i think, with nothing to gain. I also used the original darlington but for the npn used a standard bc547 with approx. beta 130, and worked great.
I would like to increase the output drive capability of the Fetboy and would like to know the options. I´ve been messing with supply voltages, up to 30 volts and custom-biasing the fets for these voltage, and this way i can squeeze a couple more volts out of it at the expense of higher dissipation...any other transformerless options?
I noticed that at 30 volts my Fetboy is quieter, i mean, a different kind of noise, less noticeable for the same gain amount.
Something odd: there´s some noise with the gain totally ccw with no input, the noise gradually dissapears until i reach 9:30 o´clock and starts to increase normally from here...but this noise isn´t noticeable with normal operation. But this bothers me, any ideas?
Thanks!
I´ve been playing with the fetboy circuit for a while and love it. I´m getting about 7.2 volts on the output (unbalanced and transformerless) before the output begin to clip. i sticked to the original 47k resistor value as higer values clipped one side of the waveform too early. Less than 42k is playing with fire i think, with nothing to gain. I also used the original darlington but for the npn used a standard bc547 with approx. beta 130, and worked great.
I would like to increase the output drive capability of the Fetboy and would like to know the options. I´ve been messing with supply voltages, up to 30 volts and custom-biasing the fets for these voltage, and this way i can squeeze a couple more volts out of it at the expense of higher dissipation...any other transformerless options?
I noticed that at 30 volts my Fetboy is quieter, i mean, a different kind of noise, less noticeable for the same gain amount.
Something odd: there´s some noise with the gain totally ccw with no input, the noise gradually dissapears until i reach 9:30 o´clock and starts to increase normally from here...but this noise isn´t noticeable with normal operation. But this bothers me, any ideas?
Thanks!