The following procedure will result in excellent AM transmit operation with the FT-100D. The User's Manual does not include any guidance regarding this. For this discussion I assume HF AM operation.
- Install the 6 kHz filter. You need the filter in order to have proper AM operation.
- Turn on the unit while holding in the A, B and C buttons in order to access the sub-menu "F" functions.
- Place the unit in AM mode.
- Set the MIC gain setting to 17 (seventeen).
- Using the F51 function, key the mic and set your un-modulated carrier output power to 25 Watts, no higher.
That's it. You should now have 100 Watts PEP on voice peaks which is 6 dB (4 times) the un-modulated carrier power.
Extra hints: Set function F15 to 170 in order to avoid non-linear compression on voice peaks. But note the original setting and restore F15 to the factory setting when you operate SSB and CW. You should have 100 Watts output in CW mode when F15 is properly set.
You can use the speech processor during AM operation but you must not exceed a setting of 17 when using it, just as with non-processed operation. The PROcessor control is simply a second MIC gain control which over-rides the MIC gain control setting whenever you enable the PROcessor. The FT-100D actually does not allow you to vary the compression percentage.
Have fun on AM with the FT-100D. I get excellent audio reports and even operate 1000 Watts PEP (250 Watts un-modulated carrier) using an SB-220 amplifier with the FT-100D.