Mutchus

Build a Simple Solar Powered Long Range FM Transmitter Circuit Diagram . This is very stable, harmonic free, long range fm transmitter circuit which can be used for fm frequencies this one is unique in that it runs completely on solar power. No battery is required. As long as the sun is shining on the PV panel, the transmitter will transmit. The transmitter bug is useful as a "remote ear", and can be used for anything from listening birds to surveillance work. The mic preamp and oscillator circuits were borrowed from a common circuit found around the Internet, a regulated solar power supply and an RF amp that extends the range of transmitter and improves frequency stability were added.    Simple Solar Powered Long Range FM Transmitter Circuit Diagram Theory The solar power supply consists of a small 18V PV panel which charges a 1000uF electrolytic capacitor. The capacitor keeps the circuit running during brief interruptions of light, such as a bird flying over the PV panel. T...

Anyone who has designed circuits using the 555 timer chip will, at some time have wished that it could be programmed for longer timing periods. Timing periods greater than a few minutes are difficult to achieve because component leakage currents in large timing capacitors become significant. There is however no reason to opt for a purely digital solution just yet. The circuit shown here uses a 555 timer in the design but nevertheless achieves a timing interval of up to an hour! The trick here is to feed the timing capacitor not with a constant voltage but with a pulsed dc voltage. The pulses are derived from the un smoothed low voltage output of the power supply bridge rectifier. The power supply output is not referenced to earth potential and the pulsing full wave rectified signal is fed to the base of T1 via resistor R1. A 100-Hz square wave signal is produced on the collector of T1 as the transistor switches. The positive half of this waveform charges up the timing capacitor C1 via ...

Christe is a very well known projector manufacturer. The opening of The Atlantic in Dubai was, in fact, done using the company's projectors. They are at Gitex to showcase some of their new products this year. One of them is the Christie J series range, a compact (in its class) projector solution that combines the best of the company's innovations into one affordable package (if ever these things can be affordable). The most interesting feature of the projector is the Christe Twist, a hardware-based pixel mapping technology that can adjust any image onto the surface it is projecting on, and stitch multiple images into one seamless image. An example is below. The Christe J series is also fitted with the 3-chip DLP platform along with 22,000 lumens of Xenon brightness to help deliver proper color accuracy and clean, crisp images. The J series comes in various low to high-end models, with the Christe Roadster HD20K-J featured above carrying a price tag of USD 80,000.

Anyone who has designed circuits using the 555 timer chip will, at some time have wished that it could be programmed for longer timing periods. Timing periods greater than a few minutes are difficult to achieve because component leakage currents in large timing capacitors become significant. There is however no reason to opt for a purely digital solution just yet. The circuit shown here uses a 555 timer in the design but nevertheless achieves a timing interval of up to an hour! The trick here is to feed the timing capacitor not with a constant voltage but with a pulsed dc voltage. The pulses are derived from the un smoothed low voltage output of the power supply bridge rectifier.  Extend Timer Range Circuit  The power supply output is not referenced to earth potential and the pulsing full wave rectified signal is fed to the base of T1 via resistor R1. A 100-Hz square wave signal is produced on the collector of T1 as the transistor switches. The positive half of this waveform c...