Noise Blanker Mod for Power Line Noise on the FT1000MP Mark V:
I have been experimenting & comparing the circuitry on various radios over the
past weeks. The FT1000MP MK5 does not seem too good with power line noise
especially on weak signals. The Kenwood TS940 was found to have the best noise
blanker compared to many other radios. I have come up with a very simple
modification that may be useful to many that have very bad power line noise but
don't mind blanking it & putting up with slight distortion on strong signals.
This mod will however only make NB A work & NB B will have very bad distortion
on all signals. The modification greatly improves the ability of receiving weak
signals using NB A. The mod will reduce most S9 power line noise to S1.
1/ Short out Diode D2009 with a wire link ( Located on the IF-Unit PC Board )
The diode is a glass type & is accessible between the IF Noise blanker coils
T2001 & T2002. Just solder a wire link across the diode.
2/ Make sure that coils T2001 & T2002 are adjusted for maximum as per the
service manual. ( My unit was not optimum )
This is an initial modification & further experimenting needs to be done with
the NB AGC feedback circuit to reduce the strong signal distortion with the
noise blanker on.
I hope that this help some that require better noise blanker performance.
Regards Mark VK5EME
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