Channel selecting apparatus employing frequency synthesizer

H - Electricity – 03 – J

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

365/5

H03J 1/00 (2006.01) H03J 3/00 (2006.01) H03J 5/00 (2006.01) H03J 5/02 (2006.01) H03L 7/10 (2006.01)

Patent

CA 1135426

ABSTRACT OF THE DISCLOSURE A tuner comprises a local oscillator including a variable capacitance diode. The output signal of the local oscillator is frequency divided by a prescaler and the frequency divided output is applied to a phase locked loop. The phase locked loop is structured such that the phases of the output signal of the prescaler and a reference frequency signal are compared and the signal associated with the phase difference is smoothed by a low pass filter and the smoothed output is applied to the variable capacitance diode as a tuning voltage. The low pass filter includes a smoothing capacitor. A tuning unlocked state is detected when the terminal voltage of the smoothing capacitor is stabilized at the source voltage or is stabilized at 0 V. Upon detection of the tuning unlocked state, the tuning voltage applied to the variable capacitance diode is increased (when the smoothing capacitor is stabilized at the source voltage) or decreased when the smoothing capacitor is stabilized at 0 V), thereby to forcibly return to a lockable region. Thereafter a locked state or a normal reception state is established by a normal operation of the phase locked loop.

339357

LandOfFree

Say what you really think

Search LandOfFree.com for Canadian inventors and patents. Rate them and share your experience with other people.

Rating

Channel selecting apparatus employing frequency synthesizer does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Channel selecting apparatus employing frequency synthesizer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Channel selecting apparatus employing frequency synthesizer will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFCA-PAI-O-384858

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.