A few more observations on my FT-817 , after studying the specs of the final amplifier it became aparent that the "FETs" used in the final are extremely robust ( ) and can safely run 10 watts out per piece , each device can disipate 10 watts of heat with a max junction temp of 175C . I decided to modify some parameters in the radio just to see what could be accomplished , in fact the radio at max power was outputing 4 watts at 1.88 amps , removing the transmit limiting current completely in hf only (HF1IC1 ,2 and 3 and increasing the drive (HF1H1 , 2 and 3 see the alignment on egroups) the radio ran 10 watts at 9-13 volts with 2.5 amps total consumption , simple math proved that the TX was 50% efficient and max current parameters were never exceeded , however I did not test any further and suspect that since the transmitter was probably running full bore there was probably no headroom left for ALC so I then adjusted the IC settings for 7 watts and the drive "H1" settings for a max of 6 watts , alc was not affected and so I left it this way . I realize that this represents a very small DB increase going from 4 to 6 watts however I felt that this setting was the best option in high power setting ( the rig has 4 switchable settings with a warning power icon in the highest setting when on battery power )
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