Also, long tailed pair phase inverters are liably to oscillate if you feed them with too low frequencies. C12 is there as a quick fix to stop this, but for a proper design I would reduce the value of C11 to 4n7 for a roll-off of 17Hz.
For the grid stop of the output, I had try bigger resistor like 10 K with no result justifing them.
I will try with lower capacitor in C11 and I 'll get back with the result
Thank's
I will try with lower capacitor in C11 and I 'll get back with the result
Thank's
One more thought- you might be having a negative resistance condition in the screens as you push it hard and the supplies sag. That could cause an oscillation burst. I haven't experienced this myself, but I've sure heard about it.
Doesn't that only apply to tetrodes?SY said:One more thought- you might be having a negative resistance condition in the screens
How much in (%) ripple is acceptable on the plate and on the screen voltage supply when the amplifier is driving at maximum?
I'm not sure about the voltage doubler. Does it need more capacitor?
The oscillation seem to have stop but now i'm hearing like a gost note
especially when i'm playing up the neck on the guitar only when i'm driving the amp at maximum.
Any hint?
I'm not sure about the voltage doubler. Does it need more capacitor?
The oscillation seem to have stop but now i'm hearing like a gost note
especially when i'm playing up the neck on the guitar only when i'm driving the amp at maximum.
Any hint?
I'm ignorant of what guitar guys do in that respect. It might be worth poking through the tech notes at Aiken Amplification to get a better feel for it.
Thank you guy's for all the information but my problem was that the driver was clipping before the maximum preamp signal. Now I have change that and the oscillation disapear. But now I see 120hz in my signal and I know that it come from my supply so any advice on my voltage doubler, publish earlier, will be welcome.
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