The didgeridoo is a wind instrument composed of a single large tube often used as drone instrument for backing up the mids and lows of an ensemble. A didgeridoo is played by buzzing the lips and blowing air into the didgeridoo. To play a didgeridoo continously one can employ circular breathing but the volume of air required poses a real challenge to novice players. In this paper we replace the ...

We report an electronically switchable dielectric leaky wave antenna. The main beam angle can be electronically steered using p-i-n diodes. The diodes are used as switches to control the radiation from two sets of gratings with different periods, thereby switching the main beam angle. Beam steering is achieved at a single fixed frequency; no frequency sweeping is necessary. A microwave prototyp...

Highest resolution imaging in astronomy is achieved by interferometry, connecting telescopes over increasingly longer distances and at successively shorter wavelengths. Here, we present the first diffraction-limited images in visual light, produced by an array of independent optical telescopes, connected electronically only, with no optical links between them. With an array of small telescopes,...

It has been observed that electronic magnification of imagery results in a decrease in the apparent contrast of the magnified image relative to the original. The decrease in perceived contrast might be due to a combination of image blur and of sub-sampling the larger range of contrasts in the original image. In a series of experiments, we measured the effect on apparent contrast of magnificatio...

Logic gates were fabricated from an array of configurable switches, each consisting of a monolayer of redox-active rotaxanes sandwiched between metal electrodes. The switches were read by monitoring current flow at reducing voltages. In the "closed" state, current flow was dominated by resonant tunneling through the electronic states of the molecules. The switches were irreversibly opened by ap...

Current space-based lidar systems for Earth remote sensing have a number of inherent limitations that impact their use for broader science applications. These include no cross-track coverage, fixed spatial sampling that forces pointing control to be performed by the spacecraft, cloud loss over many types of scenes, and, in general, lifetimes set in part by the number of laser shots fired. The E...

A planar phased-array antenna has been constructed from a 15x15 square grid of z-directed monopoles with a length of 0.475 λ, element spacing of 0.29 λ, average directivity of 20.0 dBi across all scan angles, an average H-plane HPBW of 37 degrees, an average E-plane HPBW of 23 degrees, and an efficiency of 99.6%. Two current distributions are tested: uniform and binomial. The binomial current d...

The paper presents a new realization of bipolar full-wave rectifier of input sinusoidal signals, employing one MO-CCCII (multiple output current controlled current conveyor), a zero-crossing detector (ZCD), and one resistor connected to a fixed potential. The circuit provides the operating frequency up to 10 MHz with increased linearity and precision in processing of low-level input voltage sig...