Mark V


 NB2 Mod






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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This site was last updated 03/05/08