Akula eternal lantern 4

[hartiberlin]

Yes, I have already tried a large value choke with not much change, but maybe
including the large filter cap as well will help. I have found however that the power supply regulator
is OK at lower pulse frequencies if I keep the pulse widths short.

you really need this Filter capacitor otherwise it is no lowpass filter and it will not help

[itsu]

All my yellow traces are only measured directly on the base/gate.

The purple trace (in some screenshots) is at the input of the circuit, meaning before the 10 Ohm / 10nF RC.

Regards Itsu

[hartiberlin]

I find it really strange that in theAkula scope shots there is on the yellow base signal
3 different states like high , mid and low...
Why is the base signal going back to mid state after just a few nanoseconds of
on time ?
does anybody know , why this happens ?

[hartiberlin]

All my yellow traces are only measured directly on the base/gate.

The purple trace (in some screenshots) is at the input of the circuit, meaning before the 10 Ohm / 10nF RC.

Regards Itsu

Okay,  I  see then your signal from the drain or collector effects the base signal by some kind of capacitive coupling between the drain and gate capacitor or collector and Base diodes..
otherwise it is note possible that one could get such a burst on the base signal when pulse width is so low....so the gate or base is affected by the drain or collector...

[Void]

I find it really strange that in theAkula scope shots there is on the yellow base signal
3 different states like high , mid and low...
Why is the base signal going back to mid state after just a few nanoseconds of
on time ?
does anybody know , why this happens ?

Can you post a scope shot. Could what you are calling a high state on the base
be overshoot, and then it falls back to its high pulse level, and the low state is base pulse off?