I have a 47uF Ampicillin cheap online capacitor and a 2.5V – 3.5V solar cell. I hook them up together (+ to red, buy Ampicillin – to black) and it charges up and stuff, then I take off the order Union Bank Ach amoxil solar cell, add an LED and it blinks then quit. When I hook up the LED while Minocin buy amoxil NVM Private Equity Limited the capacitor is charging, it faintly glows (it runs on 2.6V). I want to build a symet or another BEAM bot, but how do I get it to charge up and dump it out (kinda like a balloon) instead of running it through? I think I’ll need some transistors, so can you give me a nice buy cheap ampicillin schematic with the stuff I need? (like PNP and NPN stuff)
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It’s not surprizing the LED just blinks, your capacitor isn’t big enough to deliver a current for very long.
47F charged up to say 3V holds a charge of 47×3 = about 140 uC or 0.14 mC (millicoulombs). If you have a high brightness LED that only takes 1mA current, the capacitor will light it for about 0.14 seconds. If it’s an ordinary LED that takes say 20mA, it will light for a about 0.007 sec.
You can get electrolytic capacitors with sizes like 47,000 uF, or even 1-farad (1,000,000 uF) capacitors. They would run a high brightness LED for a few minutes.
Of course a 47,000 uF capacitor will also take 1000 times as long to charge up as a 47 uF.
Making a “clever” charging circuit won’t alter those basic facts, though it will inevitably be less than 100% efficient and so reduce the total energy available. Probably the most efficient option would be to use the solar cell to charge a 1.5V battery and use the battery to power whatever you want to build. If get bored waiting for the solar powered charger to do its thing, you can use a conventional battery charger.instead.
You have to make sure the solar cell is putting out enough power to light the LED. If it’s in indoor light it’s not likely there’s enough. The problem with solar cells is that they put out variable amounts of voltage depending on how much light they’re getting.
Find a voltmeter and measure how much voltage is comming out of the solar cell. If it’s not at least 2.6V the LED will glow dimly if at all. If the voltage is high when the LED is disconnected and then drops a lot when connected it probably means the cell isn’t putting out enough power. And then there’s the danger of the cell putting out too much power when in very bright light and burning out the LED.
The best solution would probably be to connect two or more cells in series and then run them into like a 5V regulator(you can buy these as 3 pin devices from Digi-Key or even your local Radio Shack). Then run the output of the voltage regulator through a resistor(chosen so that the right amount of current goes through the LED at 5V) and then to the LED. This will ensure the LED gets lit consistently with different lighting conditions.
What you need is what, in robotics, we call “solar engine” which is an electronics device which takes light energy and turns it into bursts of motor movement.
If you want to build a solar engine circuit yourself, you can find several of them here
http://www.solarbotics.net/library/circuits/se.html
You can get it as a kit here:
http://www.solarbotics.com/products/k_mse/
Also you can get everything you need for your solar/robotic project here:
http://www.solarbotics.com