Topband: Re: Receivers, Noise Blankers and Key Clicks

[VR2BrettGraham <vr2bg@harts.org.hk>]

N1EU added to KV5V's interesting observation about working close in to
loud local signals generated by FT1000s:

> I'll let Mike answer, but I was assuming he was referring to the original
> FT-1000, NOT the MP/MkV.  I've heard many FT-1000(D) transmitters on the air
> that have been burdened by noisy sidebands, and sometimes low level discreet
> spurs.

I have two within 500m of here & would tend to agree with N1EU's 
observations.
Yet KV5V's experience contradicts this somewhat & WB6RSE's efforts to see
what the proverbial whack-with-the-hand repair actually did, it all is making
sense now (original design misses something, circuitry is carried from product
to product & a little sloppy assembly to top things off from time to time).

Interestingly, 500m away one of the FT-1000s wilts when my K2/100 + 400w
is in transmit mode but not key down.  I have tried to listen with another 
antenna
myself (usually, second rig does SO2R & is on another band & has a BPF in
front of it) on the same band & could only hear phase noise at a level I could
still hear stuff through.  That doesn't make so much sense.

Just listening to the band when one of my neighbors is on, I can tell who 
it is &
which rig he's using.  Sometimes, I can do this by listening on a different 
band
altogether.  I'm sure they can do at least the former with me, but I can 
also CQ on
one band whilst listening to really weak signals on another that's just 
centimeters
away.  Without BPFs, I can hear stuff on 20 through my own phase noise as
heard on a 6m dipole equally close.  Yet things are apparently really bad for
my neighbors, even when I'm not key down.  There are several things going on
here simultaneously, as I think K8FC it was has suggested in his comments
about judging signals with the sort of receivers some rigs have.

73, VR2BrettGraham

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