Recent content by tech99

So far as I can see, and I may be incorrect here, when the switch is closed there is oscillation, which is gradually damped out by resistive and radiation losses. The energy we extract by the oscillation was contained within a radius of half a wavelength of the oscillation. If you discharge a...

I assume the wire is the same gauge, copper, enamelled? If so I strongly suspect the material of the core as the problem.

It is easy to try quenching the core if making an electromagnet. I have found it works on nails used by pupils as cores for making magnets. The untreated steel retains its magnetism and the quenched steel does not.

I have often turned nails into "soft iron", by heating and quenching them, for pupils making magnets. This makes the core lose its magnetism when the current stops.

Thank you. I think the annealing process makes the steel magnetically "soft", so it does not retain magnetism.

I remember turning mild steel into soft iron by heating it to cherry red than quenching in water.

If you use a parallel plate transmission line and tune to its resonant frequency, the electric field max position will correspond to a zero, or node, in the magnetic field. Maybe this would be a starting point.

A waveguide does not follow the shape of the ordinary resonant curve, because it has sharp cut-off on the low frequency side. The PCB example seems to be a TEM line and is not therefore a waveguide.

The Lorenzian shape arises because you have placed matter within the cavity. It appears that the material has losses at 100 MHz, which happens to be well below the cavity resonance in this case. So we have the case of a lossy waveguide operating below cut-off. I suspect, therefore, that in...

The particles are only 1/100 wavelength in size and the 100nm layer is only 20 particles thick, so scattering might be rather small.

In the Hertz experiment, he did not rely on the waves impinging on the wire. He arranged for an antenna to sample both the wave on the wire and the wave in free space. The velocity on the wire will of course differ somewhat from c, but only within a small range, and Hertz observed very large...

Hertz carried out what was, in effect, a race between a wave on a wire and a wave in free space *. If I am reading his paper correctly, he noticed that, close to the antenna, the electric wave had a velocity much greater then c. So one might ask, are electric waves limited to velocity to c when...

The propagation along a wire will depend on the shape into which it is bent and the proximity to other parts of the wire and other objects. Other modes will be excited in some cases. As Maxwell says: "In the case of electric currents, the resistance to sudden increase or diminution of strength...

2. I do not agree with this statement . The wave follows the wire, as a waveguide, so that if the wire is in a tortuous path, say a helix, the wave will tend to follow round the curves at nearly the speed of light. 3. There are actually two pulses, of opposite polarity, which originate- from...

One of these terminals has an excess of electrons on it, waiting to "go". That is the initiation of the wavefront. We require electrons to initiate the electric field of the wavefront.