Yeah, I use 470k mixer. It sounds as expected. Great!
![Very Happy :D](./images/smilies/icon_biggrin.gif)
Moderators: pompeiisneaks, Colossal
Hey Bepone, have you fixed the motorboating issue on V1?bepone wrote: ↑Thu Dec 14, 2023 12:56 pm After tweaking like crazy all morning, adding RC elements, separating decoupling the tube halves, changng pot, raising the wires in the air.. all what should stop osc - nothing. V1a stopping with LF osc only when i disconnect V1b!
Now im quitting , mazbe i ll rebuild all, but at the end i was changing amplitude in freq. gene and i saw miracle! And tragedy in the same time![]()
my problem is very strange, i tried all what i can think off, remove pot, input, ground input v1a, still is oscillating. but only at no, or low signal, when i increase input to 200mVpp then it acts normally..fred.violleau wrote: ↑Fri Jan 05, 2024 2:34 pmHey Bepone, have you fixed the motorboating issue on V1?bepone wrote: ↑Thu Dec 14, 2023 12:56 pm After tweaking like crazy all morning, adding RC elements, separating decoupling the tube halves, changng pot, raising the wires in the air.. all what should stop osc - nothing. V1a stopping with LF osc only when i disconnect V1b!
Now im quitting , mazbe i ll rebuild all, but at the end i was changing amplitude in freq. gene and i saw miracle! And tragedy in the same time![]()
Did you try to add a 100pf cap between plate and cathode of V1?
looks like it adds stability on JCM800, maybe that could help ?
Fred.
Can be.. i have cleaned totally and varnished this board but never checked conductivity between the eyeletts