/Radio/tx/sine in/PNP/sign-out/cw/
The advantage of PNP here is that it can be keyed more easily. Admitted, that this is the typically simplified thinking of cw QRP old school types. One more transistor would enable a more favorable NPN output transistor to be keyed.
On the other hand, its simplicity that the QRP design is looking for.
I forgot to mention that in some RF QRP circles, its thought that this configuration using a PNP output transistor produces less 'chirp'! This is an effect that makes the resultant CW (Morse or other ASK) sound like a chirping bird. I don't know if PNP transistor switching is helpful or not, in this respect.
I do know that the real solution is pulse shaping circuitry that allows the power to the PA stage to gently rise and fall! Contemplation and meditation!
As ever I welcome the community comments from trolls, know it all professor buggers and others. Alteratively, you could add constrictive criticism? No? Oh OK then well it was nice while it lasted.
Enjoy
73
