Just throwing this out there:
https://www.youtube.com/watch?v=CXo4hYKqIVM
FlexRadio Wideband Noise Blanker (WNB).
Yes, this video is real.
Best is to eliminate the noise source, but beyond that, SDR and DSP
can help a lot. I did a ride along with the cooperative identifying
arcing poles. I would still do that today.
I don't know if Anan has something similar but the only place I've
seen this kind of noise blanker is on a Flex.
73
Ria, N2RJ
On Mon, Oct 23, 2017 at 9:59 PM, Charles Harpole <hs0zcw@gmail.com> wrote:
> John, I have monster noise here near Bangkok and have tried several things.
> -ICOM IC-775dsp is jaw dropping good on radiated high voltage lines (it was
> made during the Russian woodpecker era), but can be defeated by other noise
> sources.
>
> -Yaesu FT-9000d has three built-in 'preselectors' ("RF u-tune" name) which
> are amazing on all kinds of noise but with strong noise, they lower the
> level but do not eliminate. Astonishingly good on radiated noise, but not
> a total solution. See
> https://www.dxengineering.com/search/product-line/yaesu-rf-mu-tune-kits-and-units/fits-transceiver-model/ftdx-9000/quantity/sold-individually
> .
>
> -K3 has about 16 settings for noise, all interwoven so that change one
> setting, it affects all the others. Extensive adjusting of these will find
> one which works well but does not totally eliminate my noise (which is
> different at different times, requiring inordinate time to readjust).
>
> -ICOM IC-7800 seems better on some types of noise, like nearly knock out
> one kind while not too good on others.
>
> These radios I have personally tested side by side.
>
> The *best *solution is the MFJ 1025 "Noise Cancelling Signal Enhancer"
> because it is a phasing tuned unit requiring two antennas. In my case with
> noise coming from NE, N, and NW only, this device absolutely eliminates my
> noise while leaving the desired signals untouched. It requires only one
> session of adjusting, but has one astonishing draw-back: it will stand very
> little RF on the second antenna input so as to limit 1.5KW operation near
> its ants.... it needs a COR relay there. Phasing is your answer because it
> really works. The built in antenna on the MFJ-1026 was not tested.
>
> Of course there are a myriad of noise types and sources. Mine are all
> radiated so the MFJ is great. Noise coming thru the AC supply line have
> other solutions discussed elsewhere. GL, 73, Charly HS0ZCW
>
> On Mon, Oct 23, 2017 at 9:27 AM, John Geiger <af5cc2@gmail.com> wrote:
>
>> I was making a rather serious (given my small antennas) effort today in the
>> Illinois QSO Party and had to deal with this intermittent noise I have here
>> for pretty much the entire contest. It is a raspy, hash type noise that
>> will be on for 2 or 3 seconds, then will end, but come back every 20 to 30
>> seconds. I have figured out it is not in my house, and doesn't seem to be
>> power line noise. At one time I thought I had localized it to a house
>> about 4 houses to the west of me, but the house is now unoccupied, but the
>> noise is still there.
>>
>> Anyways, I was using the Kenwood TS950SD which I just picked up, and it is
>> a great rig with lots of receiver tools. The noise blanker pretty much
>> knocked out the noise, but it also produced plenty of IMD products when the
>> band got busy and put a raspy sound on many of the signals, so I was having
>> to turn the NB off and on trying to make the signals as best as I could
>> with this noise. Even engaged the attenuator a few times on 40m which
>> helped a little, but also weakened signals.
>>
>> I have had a slight windfall recently and can afford to get a newer, better
>> rig if I want. Are there any recent contest quality rigs that have noise
>> blankers that take out many different types of noise, but don't mess with
>> the receive signals and receiver dynamic range? I wonder if the DSP based
>> noise blankers are better? An older rig would be ok also if it would meet
>> those criteria.
>>
>> 73 John AF5CC
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>>
>
>
>
> --
> Charly, HS0ZCW
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