It has been a known (documented by W8JI with fix) issue since the
FT-1000D.  The noise blanker contains a dual gate MOSFET connected
to the IF that runs all the time.  Instead of disabling the MOSFET,
the second gate is simply biased into an "off" state when the NB
is turned off.  Unfortunately this allows the first gate to be
overdriven by strong signals which creates IMD that is coupled
directly back into the IF.

The FT-2000 uses the same noise blanker circuit as the FT-1000,
FT-1000D, FT-1000MP, etc.

73,

    ... Joe, W4TV


On 1/3/2011 2:31 PM, Jan Erik Holm wrote:
> Is this a known issue with the FT-2000?
> /SM2EKM
> ------------
> On 2010-12-31 23:31, Joe Subich, W4TV wrote:
>>
>> or issues of IMD generated in the noise blanker (even when the NB
>> is off).
>>
>> 73,
>>
>>       ... Joe, W4TV
>>
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