I have found that the cascaded 800Hz mechanical filters in my 75A4 to have
less ringing and IMD induced noise than a TS-940 or 950SD with any of the
250, 400, or 500Hz selections.
Rather than reducing the RF gain pot I use the front end attenuator and have
an external one for the A4. None of the above are even close to ideal and
each has its better nights.
Id also suspect the 50-80KHz LC filtering of the vintage boatanchors to be
superior but reducing the front end IMD might be a chore without the
extensive mods similar to the A4. While my R-4C's had extensive filter, AGC,
product detector and audio mods, nothing was done to the front ends and it
was never a pleasant radio to use for extended times.....with all its own
faults the TS-930 that replaced it was less tiring. For about 6 months I had
one of each.
The NC-300/303 and HQ-170/180 come to mind
Carl
KM1H
----- Original Message -----
From: "Tree" <tree@kkn.net>
To: "Robin" <wb6tza@socal.rr.com>
Cc: "160" <Topband@contesting.com>
Sent: Tuesday, March 27, 2012 10:15 AM
Subject: Re: Topband: how to hear through static crashes?
> For me - Receiver AGC doesn't matter - typically on fast. However, I will
> back the RF gain back so that most of the static crashes do not activate
> the AGC. I will advance the AF gain to compensate. I find that setting
> things up this way allows my brain to focus on the signal without the
> signal changing amplitude due to the AGC being triggered by a static
> crash.
>
> I am not sure IF bandwidth matter that much at this point - but typically
> use 400 Hz. I also find a CW tone down around 400 Hz works well for me.
>
> Not sure any digital processing really helps with this - I haven't ever
> found something that I would say really works. Diversity seems to help -
> but only after you are using directive antennas to minimize the static if
> possible.
>
> I have done this for a very long time - from using an S line on 80 meters
> at K6RR, to a C line on 160 meters at P40V, a TS850 and K3 here at my
> station.
>
> Tree N6TR
>
> On Mon, Mar 26, 2012 at 7:57 PM, Robin <wb6tza@socal.rr.com> wrote:
>
>> Maybe this is a good time to share the techniques we individually find
>> successful for
>> hearing through the giant sparks.
>>
>> Directional receive antennas, obviously,
>>
>> Receiver AGC?
>> IF bandwidth?
>> IF and RF gain distribution? (includes antenna preamps)
>> what classes of digital processing do better?
>> what's the best way to keep the receiver processing from ringing and
>> increasing the
>> effective duration of the crash?
>> noise blanker performance?
>> post receiver audio processing?
>> can you let the IF strip "clip" in a modern receiver and be an effective
>> "peak limiter"
>> without serious ringing?
>>
>> What do YOU do? and with which receiver?
>>
>> some shared experience might remind all of us of things to try to hear
>> when the big sparks
>> are flying
>>
>> Robin, WA6CDR
>>
>>
>>
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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