For all those who wants a little more of driving power with the new IC-746,here is the way to do it easily.
Important settings pots within the IC-746 HF/VHF radio. Remove the twelve screws holding on the bottom cover. With the Radio laying flat on it's top remove the bottom cover.
Underneath the radio there is a board named MAIN UNIT (B5083J) where there are 4 important small pots provided to increase or decrease the power output in different bands as follow:
R-989 HF Power output (rated at 100W)
R-991 50 Mhz band Power Output (rated at 100W)
R-993 144Mhz band Power Output (rated at 100W)
R-994 AM Power output (rated at 40W)
R-546 Tx gain,set at factory for best linearity in TX IF (better not to play with it)
Do this totally at your own risk. Don't get more than 140 Wts in FM because with high SWR you might damage your final stage and void your factory warranty.
Note: Be sure to do all the setings over a pure 50 ohms dummy load.
On my particular radio (usa version) ser 3300++ i found a different board # and different variable resistors
THE BOARD # IS B5699G
R320-ADJ AM POWER
R317-ADJ VHF POWER
R311 ADJ 50 MHZ POWER
R306 ADJ HF POWER
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