For this mod you need an Power meter and a dummy load!
Open the transceiver case (top panel, 5 screws) as shown in the manual on page 59
Locate R1082 (HF), R1084 (6 mtr), R1086 (VHF) and R1088 (UHF) see manual page 63
For adjustment R1082 (HF): power on the Rig set Frequency to: 14,100 Mhz, Mic gain: 5, Mode USB and push PTT (don’t forget to whistle in the mic or use an audio generator set to 1,5 Khz 30mV !)
The same procedure for 6mtr (set to 52,000 Mhz), VHF (set to 145,000Mhz) and UHF (set to 435,000 Mhz)
Turn above Potis (R1082, R1084, R1086 and R1088) clockwise to maximum output
Ouput power after the modification:
HF: between 125 Watts and 150 Watts (on 40mtr)!
6M: 120 Watts
VHF: 70 Watts
UHF: 40 Watts