Pilot signal production system

Abstract

Abstract PURPOSE:To prevent the pilot signal from disturbing other signals, by changing the oscillation frequency of VCXO toward a low frequency in case the PLL has an out- of-synchronism. CONSTITUTION:A phase comparison is given through the phase comparator 11 between the output signal of the pulse generator 3 and the division output of the divider 9. The output of the comparison produces the negative control voltage Vc through the pulse amplifier 5 and the loop filter 6. The adverse bias voltage of the variable capacity diode 12 increases by the voltage Vc, and thus the oscillation frequency of VCXO including the diode 12 and quartz oscillator 13 to perform a pull-in of synchronism. The voltage Vc becomes minimum with the out-of-synchronism, and accordingly the oscillation frequency of VCXO always changes toward a low level.

Inventors

• 👤 Yoshio Kanezashi
• 👤 Hiroshi Ogasawara

Bibliographic Details