[ICOM] IC-746 Tuner Failure

[C.Whitaker]

de WB2CPN  a.k.a.  AFA3DJ
Mac, as you know by now I'm in AF MARS twice a
day.
So I have reaon to operate my AH-4 on a wide range
of frequencies.
It's possible your radio has the same situtaion my AH-4
does when the load, (antenna and feed line), is not
within the Z and j range that it can handle.
I do a frequency run to verify it can can handle the ones
I legally use, and snip or add to the antenna is any are
out of range. 
I'd try a good HF dummy load on your radio, and you can
check it on all frequencies to see if there are any holes.
There shouldn't be, but if there are the radio needs TLC
to see what's wrong with it inside the auto-tuner section.
73  Clete