Recent content by tech99

You can buy a portable compass/sundial here: https://nauticalia.com/collections/replica-navigation-instruments/products/sundial-for-travelling They also sell a portable astrolabe so you can find position (to some extent).

The "mirror drum" must be very perfect optically, difficult to achieve I think.

The initial beam from the laser must have finite diameter for it to work I think, that is why I suggested a first, round concave lens as a spreader. The final lens need to be concave cylindrical.

I think you might use a Galilean telescope arrangement. First a concave lens to expand the beam diameter, followed by a large cylindrical lens to spread the beam in the one plane.

What caught me by surprise was that although the ship was stationary, the flow of the tidal stream caused suction.

It is incredibly interesting. I have plotted actual fields in this way using models. It looks rather as if your dipole is terminated in resistors because the E-field along the dipole moves progressively in the manner of a travelling wave. I wonder what your assumptions are about this? It is also...

I have noticed the effect when sailing a little boat near a large tanker, which was anchored. As a fast tide was flowing between us, I felt myself strongly drawn towards the tanker due to the Bernoulli effect. Managed to get clear.

I understand that for switched mode power supplies, the choke input filter is more possible because the frequency is high.

The choke input filter is an excellent circuit because it has good regulation under load and uses the transformer efficiently. With a capacitor-input filter the current flows in short pulses, so that transfomer resistance has a large adverse effect. The choke greatly reduces the flow of AC to...

I suspect the camera has an automatic exposure adjustment, so that the dynamic range can be accommodated, and which will prevent reliable calibration.

Also just to mention that silver compounds should not be put into the drainage system as it is very toxic to plants and animals.

In principle, the coil can be made to present an impedance of 50 Ohms resistive by using two capacitors. The actual loss resistance of the coil is unfortunately not easy to ascertain by calculation but could be measured.

The amplifier is able to operate into any load safely, and has ample power available, so i would try a direct connection first.

It seems that you have two in-phase sources of radiation spaced apart. So you have an array. The energy absent from the minima will be found in the maxima.

The radar cross section of a sphere is simply pi r^2, its cross sectional area. The energy hitting this area is then reflected isotropically. Mie scattering will occur when the sphere is around its resonant frequency, which does not seem applicable in this case.