433MHz PLL

Discussion in 'General Electronics Chat' started by AndyPLL, May 3, 2006.

  1. AndyPLL

    Thread Starter New Member

    May 3, 2006
    Hi, I am hoping to detect the phase difference from a 433.92MHz carrier signal detected at two antennas, where one antenna is about a 1/4 wavelength further from the transmitter than the other.

    The circuit looks as follows in quote. I use PLLs to ensure phase lock on the carrier and pass the 2 signals to a phase detector:

    I hope you can understand my circuit diagram. A second Bandpass filter after the BJT Amps would double the 6dB of the first to 12dB, so I will probably put those in each line aswell.

    My questions are:

    1) Do I really need the PLLs? Can I just put the antenna signals into the Phase difference detector without phase lock, or do I really need the VCO (powered) output?
    2) If PLLs needed, what ICs do you recommend? Do I need special PLLs capable of locking onto a 433.92MHz signal? Or can I somehow use standard 4046/LM565??
    3) What IC for final phase comparator? Anything special required?

    I hope you can answer my questions!! If you can, then you have probably guessed that the circuit is designed to detect which antenna is closest to the transmitter source, within a wavelength as per diagram in quote:

    Antennae are about a foot apart.


  2. AndyPLL

    Thread Starter New Member

    May 3, 2006
  3. Grant


    Mar 5, 2006
    Aw..come on Andy, don't be like that! We thought RadioRon's advice to you was quite helpful- you are not the only one who uses another forum!