[TowerTalk] static busters
Tom Rauch
W8JI@contesting.com
Mon, 4 Sep 2000 18:18:28 -0400
> 0) Forget speakers, use earphones.
Works for me.
> 1) Put in as much attenuation as you can. This will keep the AGC
> circuit from
> going crazy. If you don't have attenuation buttons turn down the RF
> gain.
> I've used as much as 30db of attenuation at times on 160M.
I prefer very very fast AGC or a hard clipper on the audio line over
backing down the gain or attenuation.
> 2) Use the narrowest possible filters -- both IF and AF. You may have to
> diddle with filter width combinations till you find one which is optimum.
> I find using the slope tuning controls on the TS850 in combination with
> the narrow filters to be quite useful in copying through the QRN.
I mostly disagree with this. As Tom said, filters ring. ALL filters ring
when they are narrow, because narrow bandwidth limits response
time and lengthens on and off time.
This drags the crashes out and makes them longer, so you miss
more "signal" between the crashes. I often use 2.4 kHz filters or
wider for digging signals out of "rough" noise, although narrow
filters do help for "smooth noise" (like background hiss).
> 3) On 160/80/40 Beverage antennas or other "low noise" antennas can
> improve the S/N ratio.
As long as the noise doesn't come from the signal's arrival
direction.
> 6) Listen to a low CW note. It makes a huge difference trying to copy a
> 1KHz tone thought the noise versus a 500 Hz note. I don't exactly know
> why.
Most people experience that effect. Someone needs to the the
engineers who design radios, that most people who work CW on a
regular basis hate high pitched tones. Almost everyone I know like
500Hz tones or lower. Middle C seems to be about
ideal....hey....maybe that's why it's called middle C?
73, Tom W8JI
w8ji@contesting.com
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