SV: [AMPS] Re: Static discharge caused NOISE

[Tom Rauch]

> 
> No Tom I dont think so: When you use an antenna tuner you have ceramic
> material in the discharge path and do you not get piezoelectric effects?
> Making a lot of noise? I have much practical experience with a copy of the
> old Johnsson Matchbox together with a very long longwire. The antenna was
> connected to the variable capacitive divider in the matchbox and had no DC
> connection to ground. In summertime I had very often a high noise level
> that disappeared as soon as soon as I connected my NATIONAL R-175 choke
> from antenna to ground. Without this choke there was often flash-overs as
> soon as a thunderstorm was coming up.
> 
> sooner .......... Hans

Hi Hans,

I certainly agree on what you say. If something IN the tuner or IN 
the radio is arcing or generating noise from a static charge, then 
the choke (or even a leak resistor) will help because it prevents dc 
from entering the system.

But a dc ground does NOT help the noises in the antenna, or the 
corona noises from "snow static" or "rain static" or distant static 
crashes. The choke does not bypass noise, but it can prevent the 
feedline from charging up and making sparks and arcs in the tuner 
or in small components.
73, Tom W8JI
w8ji@contesting.com

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