[Elecraft] Re: KX1 noise blanker

[wayne burdick]

Andrew,

There isn't much space for a serious noise blanker in the KX1. You 
might be able to make a module that fits in the same place as the KXB30 
or KXB3080, but blankers take a lot of parts, so it would have to be 
all SMT. There are very specific height constraints on any components 
used on a module in this area.

You might be able to use a simple diode limiter. It could be placed at 
the output of the receive mixer if the noise pulses are *really* 
strong; otherwise it would have to go at the output of the product 
detector or the AF amp. Unfortunately, the signals found at even these 
stages might still be too low to allow limiting diodes to conduct. The 
ARRL Handbook may show examples of pre-biasing the diodes so conduction 
happens with smaller signals.

If blanking and limiting don't work out, you'd be left with one further 
possibility: outboard, DSP-based noise reduction. This can be very 
effective, depending on the type of noise, although it'll be more 
expensive.

73,
Wayne
N6KR

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