08 Other types of clocks

   Except OCXO, We have experimented different types of clocks. They are: Surface Acoustic Wave oscillator SAW of 315MHz, temperature compensation oscillator of 103MHz, 100MHz crystal oscilators.
Surface Acoustic Wave oscillator SAW
     Surface Acoustic Wave oscillator is a kind of high stability, low noise oscillator. Taking SAW devices as frequency control devices, it has the advantages of high base-frequency, high stability and low phase noise. So it is a device with perfect frequency selectivity. The frequency of quartz crystal oscillator can only reach 200MHz because of the technique, While the frequency of the SAW can reach 250~1200MHz. To a great extent, the SAW makes up the insufficiency of the quartz crystal oscillators'.
    Following shows the pictures and experimental data of SAW 315MHz.

Fig.8.01 SAW of 315MHz and oscillator circuit

Fig. 8.02 routine SAW oscillators' experiments  SN-20006.06.10£¬17:00

Fig. 8.03 SAW oscillators' experiment in zero magnetic fields SN-20006.06.10£¬15:00

   We can find that in zero magnetic fields, the data don't change with the direction of the experimental device, A lot of experiments of SAW had been proved that the result have nothing to do with direction of the device.

Fig. 8.04 temperature compensation oscillators of 103MHz

Fig. 8.05 100MHz crystal oscilators

    Generally speaking, the time all experiments spans longer than 5 years. And the distance of experiment is longer than 2 kilometers. In a type of experment, the clock is changed time after time, the pose of clock is adjusted time after time, the position is changed time after time, including these instance combinations above. All the experiments indicated that the result had nothing to do with space directions in zero magnetic fields.

Zhan, Li Kui 6/18/2007

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