micro7311
Junior Member level 2
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Hi, I am trying to understand the circuit below. It is a SAW based 315 MHz oscillator with OOK modulation. From what I understand the SAW is used to stabilize the oscillation. Therefore, if removed the circuit should still oscillate at the desired 315 MHz frequency by C1, C2 and L1. However, when I calculate the resonant frequency, I get a value of 352 MHz. Could someone explain how this circuit is operating? The application note gives a good explanation of the rest of the design but I am still not understanding how the LC resonator part of the circuit is working. Which components combine to give 315 MHz?
**broken link removed**
![SAW.png SAW.png](https://www.edaboard.com/data/attachments/54/54793-f926c3c199335926c5f5d152f1781836.jpg)
**broken link removed**
![SAW.png SAW.png](https://www.edaboard.com/data/attachments/54/54793-f926c3c199335926c5f5d152f1781836.jpg)