同样在这个电路中我也认为在TR1的BE极间必须有一个电容才会振荡! 下面是该电路设计者的话: The coil is resonated by a 22pf preset to determine the oscillator frequency. The preset capacitor is in series with a 33pf NPO capacitor, to limit the maximum capacitance. This sets the frequency RANGE of the transmitter. The coil also has a 6.8pf capacitor fitted to set the lower frequency limit of the transmitter. This can be raised to 27pf to get to the lower VHF bands.
他只提到33P,22P,6P8等电容 我认为频率绝对不仅仅由这几个电容和L1决定的,如果只考虑这几个元件TR1是不会振荡的,不满足相位条件 所以我认为必须在TR1的BE极间必须有一个电容才满足相位条件,才会振荡。 或则他本身就利用了TR1的BE结电容来构成振荡的~~~~
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