Published:2012/9/26 21:33:00 Author:muriel | Keyword: Precise FM, Tuning Indicator | From:SeekIC
Here is an add on circuit to your FM radio for precise tuning of stations. Usually an LED indicator is provided in FM radio to see whether the station is tuned or not. But it is difficult to see the precise tuning points since the variation in the LED brightness cannot be detected easily. This circuit solves the problem.The circuit uses the Op Amp IC CA3140 as a differential amplifier to sense the voltage level between the terminals of the tuning LED. The output of IC1 drives two LEDs one Red and one Green to indicate whether the station is precisely tuned or not. If both LEDs remain off, it indicates precise tuning. If anyone LED is on, it indicates that tuning is not precise. If both LEDs remain on, it indicates that there is no signal.
Precise FM tuner Circuit
Reprinted Url Of This Article:
http://www.seekic.com/circuit_diagram/Signal_Processing/Precise_FM_Tuning_Indicator.html
Print this Page | Comments | Reading(3)
Code: