I just noticed something on my FT-1000D. While tuning 18 MHz, I notice a very
low level "image" of strong signals. I first noticed I was receiving W1AW
(S9+10 on 18.097.6) on 18.114.2 (about S0). This is a difference of about 16.6
KHz. I looked 16.6 below but heard nothing. Then I found an "image" of an SSB
signal (S9+5 on 18.129.9) on 18.113.6 (about S0) AND on 18.146.5 (again, about
S0). The tuning on the SSB signals is quite "broad", and they can't be tuned
like one would with a proper SSB signal. Also, the 18.113.6 frequency is the
same as the W1AW CW "image" because of the difference in frequency display when
shifting between CW and SSB.
I tried finding other strong signals to see if this happens otherwise in the
rig. No other really strong (S9+) signals on 18 MHz. I tried 14 MHz but could
not duplicate this (either above or below the actual transmit frequency). But,
I must say that 20m is lot busier than 17m, and this might mask the effect.
I might add that the use of the NB and pre-amp made no difference. Indeed,
changing the setting of any of the controls made no difference (even tho I did
notice a change in background noise when I swept the notch control thru its
range-yes, it was off!).
Anyone have an idea what's going on? I suspect when the sunspots come back and
signals start getting stronger I am going to have a REAL problem.
Bob, W9UI.
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