Hi Jean-Pierre,
thanks for the report! I was trying to locate an intermittent fault in the antenna system. Most times, I can go up to my full 200 W,
giving 3.5 A (16 kV rms) without problems. But sporadically already above a threshold of 1 A (4.5 kV rms), some sort of partial
discharge starts to happen, resulting in increased and erratically variable resistance and also slightly increased capacitance. It
is accompanied by strong noise emissions in the FM broadcast band (which had been hardly noticable during several former instances
of visible corona). With a piece of wire as a capacitive probe on a scope, a distinct and fast "ringing" is present on each rising
edge of the carrier sinusoid. I have tried to look for visual corona in the dark and listen for the telltale sharp hiss of voltage
breakdown, but with no definite findings up to now. At the moment all seems ok - Murphy's playing hide and seek...
Best wishes for 2009,
de Markus, DF6NM
----- Original Message -----
From: ""Jean-Pierre Méré (F1AFJ)"" <[email protected]>
To: <[email protected]>
Sent: Thursday, January 01, 2009 7:36 PM
Subject: LF: 137.750 qrss3
Hello Markus (NM)
Good copy of your signal test now !
73 HNY Jean-Pierre f1afj
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