Series Modulator

Fred send me an interesting series modulator desing using an op-amp and a 2N3055.
This "famous" design has been in use for a while by the "free radio aficionados" :pirate:
and shouldn't have any problems dealing with current to the IRF510
The test I did with just a single NPN and 2N3055 was promising and think this
design will work beautiful.
For now I will try out this series modulator to get this little rig on the air.
However, I haven't completly given up on the idea of modulating in an earlier stage.

Oh, here's the schematic of the series modulator. Thanks Fred!