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It's quite difficult to make a filter to separate one station from another when they are on different frequencies so what we normally do is use an oscillator and mixer circuit to shift the station frequency to a fixed frequency where filtering is much easier. The Oscillator frequency sets which input (station) frequency is shifted down so it can go through the filter. Look up "superhet" or to give it it's full name "superhetrodyne" for more information.
can you tell me what should be the modifications in the circuit below ,to get more radio stations, as i am getting only 1 station which is also full of noise ?
Is it would be helpful of applying this oscillator circuit (below )in above circuit ?if yes then plz tell me which terminals should be connected to where ?
The radio circuit you show is not a 'superhet', therefore you cannot apply this oscillator to it.
For me, your radio circuit is very difficult to understand, so it will be very hard to improve it.
Also, it is unclear if the one station capability is due to poor sensitivity, or due to lack of
tuning range (I think this was mentioned in another thread). Which is it?
If you really want an FM radio, you may have to move to a very different design, maybe using ICs.
mk16820, that circuit is horrible, it's a VERY crude kind of super-regenerative receiver which has poor sensitivity, poor selectivity and it receives AM, it only works as an FM receiver if it is tuned away from the center frequency (slope detection), It may also cause interference to other receivers nearby.
The oscillator you show is for producing square wave signals, it's really for driving digital equipment. It can't be used with the receiver schematic and even if it did, so many frequencies would come out of it at the same time that you wouldn't be able to select any one station from them.
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