ODP: one for the theorist

[Roman Sowa]

H field is never apart from E field, unles it is DC (well, all this
audio stuff is actually DC anyway...). Change in H-field makes
E-field and vice versa - this way we have radio waves.
E and H are more or less like voltage and current in Ohm law,
and air impedance (vacum too) is about 377 ohms, belive it or not.

Another point - wire without return path
Well, for me it is antenna. Such wire has certain impedance with
relevance to ground, and it depends on frequency. Might be real
(resistance) or complex, inductive or capacitive depending on ratio
of frequency (or actually a wave length) to wire length.

Roman
now antenna people will start to jump on me >:-P


> -----Oryginalna wiadomość-----
> Od:	Haible Juergen [SMTP:Juergen.Haible at nbgm.siemens.de]
> Wysłano:	14 lipca 1999 13:14
> Do:	Roman Sowa; synth-diy at mailhost.bpa.nl
> Temat:	RE: one for the theorist
> 
> 
> Sure, but using open wires you're probably leaving the reign of 
> approximations where values such as inductance (and mutual
> inductance) are making sense. The current density (which is
> responsible for the magnetic field) is not just determined by
> the current in the wire anymore, but also by the d/dt of the electric
> field. That is, capacitive and inductive effects are not independent
> of each other anymore.
> 
> JH.