[CQ-Contest] FT-1000D HUM in RX audio

[Bob AD5VJ]

I have a FT-1000D which, with the RF and AF gain CCW (off) and everything
disconnected from the radio except a Heil PRO headset or my Yeasu SP-8
filtered speaker, has a very noticeable 60 Hz hum on both channels (ie.,
main and sub in "stereo"). After searching in Google with various phrases,
all they can talk about is ground loops.

I am about to start throwing filter caps at the headset and the external
speaker, but would rather solve the problem (if there is a known problem)
rather than just the symptom. The hum level doesn't vary with the AF gain
control, the AF output is clean and the hum disappears into the "normal"
volume level.

I just bought a RASCAL GLX last week and hooked it up a couple days ago. The
hum also appears in this setup but the hum doesn't appear in the digital
decode window. I can hear it in the head set for a second as I send, then it
disappears into the sounds of the monitor signal as my signal is sent back
to the headset. It doesn't appear in the transmitted signal in the decode
window however.

I've been living with the hum for a couple of weeks now, I went to the shack
of the ham who I purchased the radio from and he had it all hooked up when I
got there, while listening to very low signals on his headset off the
beverages I noticed no hum at all, until after I drove it home and hooked it
up here.

He uses a Heil headset which is the PRO with the phase switching in it and
also an external speaker. I use the standard Heil PRO without a phasing
switch and the SP8 external speaker. It was fine with all the other rigs I
used it on including an FT-775DSP and an FT-1000MPMKV and Icom 756PROII that
I had before.

Has anyone fixed this in the 1000D?

Thanks for listening and looking forward to your responses,

73, Bob AD5VJ