Troubleshooting TX side of Easy BITX with my homebrew N5ESE Classic RF Probe

VFO output of the Raduino board in Easy BITX is from the 34th pin of the long 40 pin connector soldered to the PCB. That goes to the input of T3 trifilar transformer. From T3 it goes to C42 capacitor at the input of Q10 transistor as well as to the BAT54S diode ring mixer. I checked sequentially at this point and then at the input of the final IRF 510 transistor and found increase in RF voltage while modulating with mic. But no output was noted at the antenna output. So I presume that the IRF 510 final transistor has blown off!