| 摘要 |
A signal generator includes a high frequency oscillator such as a quartz crystal oscillator at a frequency of 4.19 MHz, a low frequency quartz oscillator with a frequency of 32 kHz, a beat frequency generator for producing a correction signal which is transmitted to a programmable frequency divider, and an electronic switch for periodic switching of the high frequency quartz oscillator. By periodically switching-on the high frequency quartz oscillator, comparing its frequency curve with that of the low frequency quartz oscillator and and appropriately adjusting the programmable frequency divider, the advantages of long term stability, temperature of behavior and aging of a high frequency oscillator are combined with the low current consumption characteristics associated with the low frequency quartz oscillator, whereby the life of a battery powering the signal generator can be substantially extended. |
