Le lundi 31 juillet 2006 à 08:57:27, [email protected] a écrit:
> Remember that when the antenna was tuned, one suggestion was to place a
> matching transformer with TV Horizontal Ferrite core in the circuit. When
> that was done, the waveform on the scope turned to garbage. (high in odd
> order harmonics)
/ ... /
> Any ideas on how to approach this waveform problem?
Hi Jay,
I had a similar problem when experimenting with a 1:1 transformer in between
the LF transmitter and the 50 ohm dummy load. The transformer was wound on a TV
HV transformer (3C90 iron dust or the like) It appeared the transformer did
not perform as expected because of the two C-shape halves glued together with
a gap. There is no need for a gap in a matching transformer. The gap reduces
the reactance of both windings and therefore needs to be removed, or the turn
number increased if size permits.
With a much higher inductance (> 200 ohms) there is still a small phase
difference
between current and voltage (the phasemeter shows an inductive load) but the
amplifier does not complain anymore.
73 de Michel f5wk
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The Bat 3.80.06
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