I followed this circuit http://www.saers.com/recorder/craig/TENewsV2/TENews68/RadioWaveEnergy.jpg to harness radiowave and turn it into dc and it seems to generate around 1.4 volts but interestingly enough when i measure the amperage of the current there is zero amp...so i am looking on how to get the amp from the circuit kindly advise
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You will only get microwatts (or less) from a radio antenna. – Peter Bennett Apr 15 '16 at 03:30
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How did you measure the current? To measure any current you need a load connected to the circuit. Anyway, Peter is right, the power from such a circuit will be very low. – Claudio Avi Chami Apr 15 '16 at 03:59
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Something that may be useful to understand: http://electronics.stackexchange.com/questions/175121/rf-energy-harvesting – Andy aka Apr 15 '16 at 08:02
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When you know the load (resistance) and the voltage across it, you can calculate the current with V=IR.
Assuming your multimeter has a 1 Megaohm input, that means you are getting 1.4 microamps (uA) -- This agrees with @PeterBennett estimate of microwatts. Power = V^2 / R = 1.4*1.4/1E6 = 1.96uW. Seems pretty good for a first try!
Depending on how precise your meter is, you could try a 1K load, we can estimate this would see 0.044V across it.
Edit: In addition to trying different known loads, see this post for tips on determining the input resistance of your meter -- If it is a decent new one it might be higher than 1Mohm, in which case the power you're getting could be less than a mirowatt.
Keegan Jay
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