Abstract
An analog electrical technique is presented to measure a small current that is generated by a thermionic converter when it is operated at low temperature regime. Direct and inverse currents are generated simultaneously in a thermionic converter at steady state (emitter temperature > 1500K); although, at low temperature regime any of them may be more significant. Important information is obtained from a thermionic converter when it is operated at low temperature regime, particularly, when the inverse current is generated from the collector to the emitter (inverse current ? 1 ?A). An operational amplifier is used as a buffer circuit to measure the voltage in a small capacitor. A mathematical treatment was made from the voltage data obtained from the charged capacitor to measure indirectly the current generated by the thermionic converter. It was possible to measure a small current like 1 ?A by this technique.References
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