Dear all,
the different efficiency of a typical radio amateur LF aerial between
winter and summer is due to the frozen ground in winter, causing lower
ground loss. Therefore I have employed a matching transformer between
feeder cable and the aerial feed point using three taps on the
secondary.
This has already been confirmed earlier by Swiss LF operators in the
"good old CW period" around 1998-2000. But I also remember that british
LF operators had problems to confirm this, possibly because of less and
weaker freeze periods in wintertime in their country.
This transformer has also the task to separate the safety ground in the
shack and the outside aerial ground, otherwise I have noticed that
plugging and unplugging equipment in the shack may change aerial
tuning.
HW?
73 Ha-Jo, DJ1ZB
"rn3agc" <[email protected]> schrieb:
> Hi Stefan,
> The aerial doesn't work in the summer...
> In the winter on PA 24V 12A, now only 7A with 32V.
>
> Frequency of a synthesizer "jumps", this is something new..
>
> 73
> Andrey
>
>
> > ...is currently transmitting DFCW-60 at 137.7775 kHz, visible in YO
> > http://qsl.net/4x1rf/yo/lfgrabber.htm
> >
> > Maybe the signal comes up here in west EU later...
> >
> > 73, Stefan/DK7FC
> >
>
>
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