Showing posts with label solar. Show all posts
Showing posts with label solar. Show all posts
Friday, December 12, 2014
Solar Battery Charger Circuit Schematic
Here is a solar charger circuit that is used to charge Lead Acid or Ni-Cd batteries using the solar energy power. The circuit harvests solar energy to charge a 6 volt 4.5 Ah rechargeable battery for various applications. The charger has Voltage and Current regulation and Over voltage cut off facilities.
Friday, September 19, 2014
Solar Power Supply
This circuit delivers either 4.8 or 7.2 V regulated at 15 mA with a 3-V input from a bank of photocells. Rl should be 453 kQ for a 7.2-V output and 274 РЁ for a 4.8-Vdc output. Regulator efficiency is around 70%. This should be considered when selecting suitable solar cells.
Solar Power Supply Circuit diagram :
Solar Power Supply Circuit diagram :
Sunday, August 17, 2014
RGB Solar Lamp
This deluxe solar-powered light uses a battery and solar cells salvaged from a solar lamp with a four-cell battery (4.8 V nominal terminal voltage).
RGB Solar Lamp Circuit Diagram
The schema can operate from any DC voltage around this value and its current consumption, at 20 mA, is low. This means that the battery can give up to five days of operation. The schema consists of an Atmel ATtiny microcontroller which drives a red, a green and a blue LED directly from three port pins. Series resistors are of course included to limit the LED current. The microcontroller drives the LEDs in sequence to produce an RGB running light effect. The microcontroller is also responsible for ensuring that the light automatically switches on when it gets dark and off when it is light. The light sensor is made from one of the solar cells from a bro-ken solar lamp (it is more common for the battery to fail rather than the solar cells).
The power output of this cell is not important, as the microcontroller only measures its output voltage using its internal A/D converter connected to pin PB4. The project is ideal for beginners, as a ready-programmed microcontroller is avail-able from the Elektor Shop (order code 100581-41).
Saturday, August 16, 2014
Solar Powered Animal Scarer
Here is a solar powered Flasher to scare away the nocturnal animals like bats and cats from the farm yard or premises of the house. The brilliant multicolored flashes confuse these animals and they avoid the hostile situation. It is fully automatic, turns on in the evening and turns off in the morning.
The schema has an LDR controlled oscillator built around the Binary counter IC CD 4060.The functioning of the IC is controlled through its reset pin 12. During day time, LDR conducts and keeps the reset pin of IC high so that it remains dormant. During night, LDR cease to conduct and the reset pin will be grounded through VR1. This triggers the IC and it stats oscillating using the components C1 and VR2. Output pins 7, 5 and 4 are used to power the LEDs strings.
VR1 adjusts the sensitivity of LDR and VR2, the flashing rate of LEDs. High bright Red, Blue and White LEDs are used in the schema to give brilliant flashes. Red LEDs flash very fast, followed by blue and then White. White LEDs remains on for few seconds and provide light to a confined area. More LEDs can be added in the strings if desired. The schema can also function with 12 volt DC.
Animal Repellent Circuit Diagram
The schema has an LDR controlled oscillator built around the Binary counter IC CD 4060.The functioning of the IC is controlled through its reset pin 12. During day time, LDR conducts and keeps the reset pin of IC high so that it remains dormant. During night, LDR cease to conduct and the reset pin will be grounded through VR1. This triggers the IC and it stats oscillating using the components C1 and VR2. Output pins 7, 5 and 4 are used to power the LEDs strings.
VR1 adjusts the sensitivity of LDR and VR2, the flashing rate of LEDs. High bright Red, Blue and White LEDs are used in the schema to give brilliant flashes. Red LEDs flash very fast, followed by blue and then White. White LEDs remains on for few seconds and provide light to a confined area. More LEDs can be added in the strings if desired. The schema can also function with 12 volt DC.
Animal Repellent Circuit Diagram
The schema uses a solar powered battery power supply. During daytime, battery charges through R1 and D1.Green LED indicates the charging mode. During night time current from the solar cell decreases and D1 reverse biases. At the same time D2 forward biases to provide power to the schema. Resistor R1 restricts the charging current and the high value capacitor C1 is a buffer for current.
Animal Scarer Solar Power Supply
Tuesday, August 12, 2014
Simple Solar Powered Long Range FM Transmitter Wiring diagram Schematic
Build a Simple Solar Powered Long Range FM Transmitter Circuit Diagram. This is very stable, harmonic free, long range fm transmitter schema 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 diagram were borrowed from a common schema 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 schema running during brief interruptions of light, such as a bird flying over the PV panel. The 18V is regulated down to 9V with the 78L09 regulator IC to provide a steady 9V supply for the rest of the schemary. With the PV panel shown above, the schema will only work when direct sunlight is shining on the panel. A larger panel that can provide 22mA at 12V during cloudy conditions would extend the diagram operating conditions.
The Electret microphone is biased with a 33K resistor, the resistor value can be changed to vary the amount of modulation and optimize the performance of specific microphones. The microphone signal is amplified by a 2N3904 audio amplifier. This signal is sent to the 2N2222A oscillator stage where it changes the oscillators frequency (FM). The oscillators operating frequency is set by L1, the 6pF capacitor and the 5-20pF variable capacitor. With L1 wound as specified on the schematic, the schema will operate near the low end (88Mhz) of the FM broadcast band.
The output of the oscillator schema is taken from a tap on the oscillator coil L1 and fed to the RF amplifier 2N2222A transistor. The output of the RF amp is run through a low pass PI filter to remove unwanted RF harmonics before the signal is sent to the antenna.
Specifications
Output Frequency: 88Mhz nominal, can cover 88-108Mhz with coil adjustments
Input voltage: 11-18VDC
Operating current: 22mA @18VDC
DC input to RF amp: 81mW
RF output power: 40mW (approx.)
Construction
The prototype schema shown in the top photo was built using the "dead bug" construction method, it was laid out as the schema was designed. A second-generation version of the schema was built using a home-made printed schema board, this is shown in the second photo. The frequency stability of the transmitter was greatly improved when it was built with the schema board. Artwork for the PCB is available at the end of this page.
It important to mount the oscillator components solidly so that they dont move around and cause unwanted frequency shift. The component leads for all of the RF wiring should be kept short. The coils were wound on a #2 Philips screwdriver shaft and stretched out a bit. To improve the diagram frequency stability, wind the oscillator coil on a 1/4" form, then heat the coil in an oven at to anneal the metal. A layer of polystyrene "Q dope" can be painted onto the coil to further improve the stability.
Another trick that will improve the transmitters frequency stability is to build it into a metal box that is surrounded by an insulating material such as styrofoam or bubble-wrap. If the transmitter box is mounted in the shade, it will be less likely to change frequency due to solar heating and cloud shading.
Antennas
This schema will work with a variety of antennas. An adequate short-range antenna can be as simple as a 1 to 2 wire connected directly to the schema. A resonant antenna such as a tuned dipole or a vertical antenna will greatly extend the range of the transmitter.
A resonant half-wave diple antenna for 90Mhz can be made with two 2.6 foot pieces of wire fed in the middle, using the classic dipole formula: quarter wave length (feet) = 234 / frequency (Mhz). the PV panel and wiring should be kept away from the antenna, or in the case of a short whip antenna, the PV wiring can be run in the opposite direction as the antenna to act as the other half (counterpoise) of a dipole.
Alignment
The schema can be aligned in the laboratory by putting 12V to 18V DC across the PV panel to power the regulator. Tune your receiver to a blank spot on the lower end of the FM band and adjust the frequency calibration trimmer until you hear the microphone signal. Turn the trimmer very slowly, alignment takes a light touch. Dont turn the receiver volume up too much or you will get audio feedback. A frequency counter may be useful for setting the output frequency. It may be necessary to retune the frequency a bit after the schema has warmed up in the sun.
The output capacitor should be tuned for the maximum transmitted signal, this setting varies with different antennas. The best way to do this is to connect the antenna to the transmitter and monitor the signal with an oscilloscope (100 Mhz bandwidth) connected to a nearby antenna. Adjust the control for the highest signal. If you have a receiver with a signal strength indicator, that can also be used for monitoring the transmitters output level. Adjustment of the output capacitor will pull the oscillator frequency a bit, it will be necessary to alternate between oscillator and output adjustments to fully align the schema.
Use
Place the PV panel in the sun and tune your receiver to the bugs signal, listen to the world outdoors. An analog receiver is best for picking up the signal since, unlike a digital receiver, it can be fine tuned to track the signal. I use a 1970s vintage Pioneer receiver to good effect. Once the bugs temperature has stabilized, its frequency should not drift very much.
The microphone enclosure and placement can be tuned to optimize sound reception in a particular direction. A good directional microphone can be made by putting the mic element into one end of a short piece of PVC pipe. Inserting a thin tube of porous foam into the pipe can lower the resonant nature of the cylinder.
The solar power supply consists of a small 18V PV panel which charges a 1000uF electrolytic capacitor. The capacitor keeps the schema running during brief interruptions of light, such as a bird flying over the PV panel. The 18V is regulated down to 9V with the 78L09 regulator IC to provide a steady 9V supply for the rest of the schemary. With the PV panel shown above, the schema will only work when direct sunlight is shining on the panel. A larger panel that can provide 22mA at 12V during cloudy conditions would extend the diagram operating conditions.
The Electret microphone is biased with a 33K resistor, the resistor value can be changed to vary the amount of modulation and optimize the performance of specific microphones. The microphone signal is amplified by a 2N3904 audio amplifier. This signal is sent to the 2N2222A oscillator stage where it changes the oscillators frequency (FM). The oscillators operating frequency is set by L1, the 6pF capacitor and the 5-20pF variable capacitor. With L1 wound as specified on the schematic, the schema will operate near the low end (88Mhz) of the FM broadcast band.
The output of the oscillator schema is taken from a tap on the oscillator coil L1 and fed to the RF amplifier 2N2222A transistor. The output of the RF amp is run through a low pass PI filter to remove unwanted RF harmonics before the signal is sent to the antenna.
Specifications
Output Frequency: 88Mhz nominal, can cover 88-108Mhz with coil adjustments
Input voltage: 11-18VDC
Operating current: 22mA @18VDC
DC input to RF amp: 81mW
RF output power: 40mW (approx.)
Construction
The prototype schema shown in the top photo was built using the "dead bug" construction method, it was laid out as the schema was designed. A second-generation version of the schema was built using a home-made printed schema board, this is shown in the second photo. The frequency stability of the transmitter was greatly improved when it was built with the schema board. Artwork for the PCB is available at the end of this page.
It important to mount the oscillator components solidly so that they dont move around and cause unwanted frequency shift. The component leads for all of the RF wiring should be kept short. The coils were wound on a #2 Philips screwdriver shaft and stretched out a bit. To improve the diagram frequency stability, wind the oscillator coil on a 1/4" form, then heat the coil in an oven at to anneal the metal. A layer of polystyrene "Q dope" can be painted onto the coil to further improve the stability.
Another trick that will improve the transmitters frequency stability is to build it into a metal box that is surrounded by an insulating material such as styrofoam or bubble-wrap. If the transmitter box is mounted in the shade, it will be less likely to change frequency due to solar heating and cloud shading.
Antennas
This schema will work with a variety of antennas. An adequate short-range antenna can be as simple as a 1 to 2 wire connected directly to the schema. A resonant antenna such as a tuned dipole or a vertical antenna will greatly extend the range of the transmitter.
A resonant half-wave diple antenna for 90Mhz can be made with two 2.6 foot pieces of wire fed in the middle, using the classic dipole formula: quarter wave length (feet) = 234 / frequency (Mhz). the PV panel and wiring should be kept away from the antenna, or in the case of a short whip antenna, the PV wiring can be run in the opposite direction as the antenna to act as the other half (counterpoise) of a dipole.
Alignment
The schema can be aligned in the laboratory by putting 12V to 18V DC across the PV panel to power the regulator. Tune your receiver to a blank spot on the lower end of the FM band and adjust the frequency calibration trimmer until you hear the microphone signal. Turn the trimmer very slowly, alignment takes a light touch. Dont turn the receiver volume up too much or you will get audio feedback. A frequency counter may be useful for setting the output frequency. It may be necessary to retune the frequency a bit after the schema has warmed up in the sun.
The output capacitor should be tuned for the maximum transmitted signal, this setting varies with different antennas. The best way to do this is to connect the antenna to the transmitter and monitor the signal with an oscilloscope (100 Mhz bandwidth) connected to a nearby antenna. Adjust the control for the highest signal. If you have a receiver with a signal strength indicator, that can also be used for monitoring the transmitters output level. Adjustment of the output capacitor will pull the oscillator frequency a bit, it will be necessary to alternate between oscillator and output adjustments to fully align the schema.
Use
Place the PV panel in the sun and tune your receiver to the bugs signal, listen to the world outdoors. An analog receiver is best for picking up the signal since, unlike a digital receiver, it can be fine tuned to track the signal. I use a 1970s vintage Pioneer receiver to good effect. Once the bugs temperature has stabilized, its frequency should not drift very much.
The microphone enclosure and placement can be tuned to optimize sound reception in a particular direction. A good directional microphone can be made by putting the mic element into one end of a short piece of PVC pipe. Inserting a thin tube of porous foam into the pipe can lower the resonant nature of the cylinder.
Parts
1X GM 684 60 mA 18V PV panel (available from Electronix Express) or equivalent
1X 78L09 voltage regulator IC
1X 1N4001 diode
1X 2N3904A transistor
2X 2N2222A transistors
1X 1000uF 25V electrolytic capacitor
1X Electret microphone
4X 100nF capacitors
2X 22nF capacitor
1X 1nF capacitor
1X 3pF silver mica capacitor
1X 6pF silver mica capacitor
1X 10pF silver mica capacitor
1X 20pF ceramic disk capacitor
1X 27pF ceramic disk capacitor
2X 5-20pF (or similar) miniature variable capacitor
1X six hole ferrite choke or equivalent
1X 100 ohm 1/4W resistor
1X 470 ohm 1/4W resistor
1X 10K 1/4W resistor
1X 20K 1/4W resistor
1X 33K 1/4W resistor
1X 47K 1/4W resistor
1X 1M 1/4W resistor
1X 1-3/4"x3" copper plated blank printed schema board
1 length of #20 tinned copper hookup wire for making two coils
1X weatherproof plastic box (recommended)
Sourced By: Copy righted : G. Forrest Cook
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