John
I have to say that 80% of the noise that impacted me on the low bands (and
even 2M) was in my house. The worst was a Cisco switch that wiped out from
1Mhz - 240Mhz. It was the switch I was using in the shack. It had some
amazing broad spurs that landed on key RF frequencies.
I spent a few days going around with a Handheld that had AM on it and
narrowing it down. I replaced about a dozen wall chargers (Garmin and
Apple being the worst).
I added Mix 31 and 43 chokes to both ends of every feedline depending on
the frequency. This also includes DC power cables. I ended up buying
about 100 of each and I have used most of them.
It was the Yankee Contest Clipper Club document on choking that got me to
dig in further into my own home. I would share the link, but I think it
would be stripped out. You can easily Google it.
If you have 100% eliminated everything internal to your QTH, that you can
ignore my comments. hi hi
Good luck in the contest, Mike va3mw
On Thu, Oct 22, 2020 at 10:04 AM Martin, LU5DX <lu5dx@lucg.com.ar> wrote:
> Hello John,
>
> In my case I use several things.
> I have two noise cancelling units:
> QRM Eliminator by SP8RSM
> JPS ANC-4
> These are no DSP but rather X-Phase type.
> I owned a Timewave DSP599zx which worked okay in many aspects, like with no
> specific EMI sources.
>
> I sold it when I bought the FTDX3000D.
> This rig is great. I have tested it during SSB and CW contests. On CW with
> the optional 300Hz roofing filter it simply outperforms other rigs I have
> used like, IC7851, K3S, IC7700, IC7600.
> The noise reduction capabilities are pretty good.
>
> I think you may have to experiment fighting the QRM based on what's present
> at your location though.
> Eventually you may want to explore with software using Linrad for example
> as a last step in your noise-fighting artifacts chain.
>
> Some videos on YouTube that may give you an overview:
>
> QRM Eliminator:
> https://youtu.be/0KJai82eP2g
> https://youtu.be/efyJRS3jbOI
>
> Linrad
> https://youtu.be/rWm38BW2-TI
>
>
> I would really suggest you consider the DX Engineering NCC2
>
> Vy 73,
>
> Martín, LU5DX
>
> El mié., 21 oct. 2020 10:19 p. m., John Geiger <af5cc2@gmail.com>
> escribió:
>
> > I made a rather serious effort in the Illinois QSO party today since I
> > used to live in IL and know a few of the operators in the contest, plus
> it
> > is only an 8 hour effort-but I wish they would move it away from football
> > season! Conditions weren't the best, but I was really suffering from
> noise
> > on 40 meters-not one specific noise source, just the crud you get from
> > living in an urban neighborhood with lots of consumer electronics and
> their
> > crummy switching power supplies and other noise makers. I am sure I am
> not
> > the only ham with this issue. The noise reduction circuit in my current
> > rig didn't do the greatest on handling this noise.
> >
> > One idea that came to me, that would be cheaper than a new rig (but less
> > fun) would be an outboard DSP unit. Does anyone have any recommendations
> > on DSP units that have good noise reduction circuits? I have seen some
> > reviews on the Clearspeech and GAP speaker units that said that after you
> > unkey after transmit you are hit with a burst of noise until the unit
> > readapts itself to the receiver noise. I don't want something with that
> > issue.
> >
> > Recommendations? Also, what radios are really good at dealing with this
> > type of noise. I have seen the FTDX3000 and K3 mentioned as having great
> > noise reduction circuits.
> >
> > 73 John AF5CC
> > _______________________________________________
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> >
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