| Author | Views | Views Today | Rank | Comments |
| 72,689 | 64 |   |
44 |
| Author | Views | Views Today | Rank | Comments |
| 72,689 | 64 | |
44 |
| This simple circuit uses an incandescent lamp to detect airflow. With the filament exposed to air, a constant current source is used to slightly heat the filament. As it is heated, the resistance increases. As air flows over the filament it cools down, thus lowering it's resistance. A comparator is used to detect this difference and light an LED. With a few changes, the circuit can be connected to a meter or ADC to provide an estimation on the amount of air flow. |
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| R1 and R2 are parallel conected? | ||
| sir, i would like toknow if this circuit can be used to detect the flow of hydrogen gas through a process of electrolysis. i am plannig to used this circuit in my project: Hydrogen torch | ||
| instead of that incandacent bulb which can be used please reply... the circuit is nice in use.... | ||
| This is an idea of the Hot-wire Anemometer.You've to heat L1,when air flow pass L1,it's cool down and it's resistance is changed along it's temperature. R4 is used to adjust the reference voltage,you've to adjust it to the highest velocity or at the position that make the LED just blind or use lower resistance,I think value not over 1k may be used. | ||
| How about substituting a tiny positive temperature coefficient (PTC) thermistor in place of L1? That would be a lot safer than breaking light bulbs, and would achive the same result. Many electronic components dealers offer them very cheap too. | ||
| i think it will not work properly | ||
| Can some one tell me about R4?... is it a varible resistor or a fixed resistor??.... I have built this circuit many of times but have not been able to get it to work..... Can anyone give me some feedback...thanks!! | ||
| sir i am going to take this as my project of present semster can i have some more details about this???? plz plz plz | ||
| hi there. nice circuit. i have some problems regarding the Incandescent lamp. i would like to implement this circuit into the pspice program but i do have problem to place the incandescent lamp. may i know, if there is a part can replace the criteria of the incandescent lamp in pspice? thank you | ||
| Sir i want to take this circiut as my annual project,so plz plz send me more details about this cct. | ||
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