Simple opamp circuit with one transistor gives reliable hot-wire anemometer for measuring flow of gases or liquids. R2 is heated above ambient temperature in Wheatstone bridge including overheat resistor R1which is calibrated to be 30% larger than cold resistance of R2. Bridge is fed from power tran. sistor which is within feedback loop of opamp th
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at senses bridge unbalance. Output of bridge is fed back to power transistor in correct phase for maintaining constant- temperature condition in which R2 is approximately equal to R1. Article covers construction of hot-wire probe made from Wollaston wire. -W. Bank, Build Your Own Constant-Temperature Hot-Wire Anemometer, EDN Magazine, Aug. 1, 1972, p 43.
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
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This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
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