[ICOM] IC-706MKIIG Issue

[KD7JYK DM09]

"It's had this issue since it was new. It appears to me that the radio 
is overly sensitive, both on HF and VHF. I bought the rig for mobile use 
but, due to this problem, it is unusable..."

Assuming it wasn't bad the day it was made...

Do all your tests with a 50 Ohm load, the antenna ports open, and 
shorted, to get a baseline of what the radio itself is doing without any 
antenna at all.

I don't have my MKIIg handy, but I recall with a MODIFIED 70 MKII, that 
the pre-amp turns on and off in odd places when tuning, so things change 
from deaf, to noisy, while spinning the dial, or, if in a memory, and 
pre-amp was a parameter on one channel, and not another, different noise 
on different channels.  When tuning, and you observe this odd behavior, 
make note of the pre-amp light.

Generally, I found the radio too wide-open for the RF cesspools of big 
cities.  It's been a while since I've been to a big town, but seem to 
recall an S-meter reading of well beyond S-9, just from all the garage 
in most towns.  Legitimate signals still come through OK, with no noise 
being heard when something was actually there, making me think the 
S-meter is just relative crap.

I last used my rig in a big city around 2009, and swore I'd never do it 
again without literally a pickup truck load of band-pass filters, just 
to make things work as expected.

To get decent usage, but still with absurdly high readings of nothing, 
just ambient RF, on VHF, pre-amp off, narrow FM, noise blanker on, and 
DSP on.  A PL decode helps, if available.

Kurt