[Elecraft] Noise Blanker

[VR2BrettGraham]

VK3HE commented:

>I have compared it to several other radios. One radio in particular the
>TS830S has  one of the most amazing all round  noise blankers. All the
>noise the Elecraft noise blanker struggles on the TS830S noise blanker
>will handle on the low threshold setting. The same results can be had on
>my FT1000D, my mobile TS480 also handles the noise in a more able
>manner. The TS830S's noise blanker is a killer on rain static on a yagi,
>the K2's struggles to cope in comparison.

Careful, it is not valid to compare the functionality of
the NB against other radios.

NBs do not work on some noises & all cause the
receiver to wilt from IMDs.

Or so we hear each time somebody wonders why
the K2 NB doesn't seem to do anything.

Strange, I also find other radios' NBs to work fine
on a wide range of noises & will do so without
adding much of anything untoward.  None of them
require scratching a transistor case with a screwdriver
to establish that the NB works - just flick the front
panel switch will suffice.

They can take a bite out of some atmospherics &
even stuff like power line noise & the British or
Chinese woodpeckers - not completely, but often
enough to be able to hear what I need to hear
through it.

But not on the K2.  The K2's NB either does
nothing or makes things worse - exactly what we
are told here is what all NBs do.

My other radios do not have AGC image responses,
nor are they so inconsistent with amount of AGC
response for a constant level signal on the various
bands.

My other radios may have NB threshold knobs, but I
rarely have to touch them.  Turn on NB, noise is
reduced or goes away, without introducing anything
untoward.

IMHO, much of the problem with the K2's NB has to
do with this variability in gain across the band,
between bands & the additional variable of AGC image
response.

The efforts to explain it away will not change the fact
that the K2's NB is the worst performing NB of any
radio I have ever used.

That the subject keeps coming up here does suggest
there might be room for improvement, but again this
is based on the invalid comparison with other radios,
so we had best shut up, mate.

73, VR2BrettGraham