I am currently working on a direction finder project for rf signals. I am attempting to use a phase detector chip to compare phases and calculate the direction. The main problem I am experiencing atm is getting the signals into the chip. I was hoping to find a reciever chip for the 433.75Mhz range. However all the ones I found included a demodulator which would mean the loss of the carrier signal (needed to compare phases). Has anyone come across an IC that can recieve the signal, amplify and filter it without demodulating it?
My other thought was that a using two basic rf reciever (not sure if it is fm or am) with an audio would work as the phase detector chip can work at low frequencies. I am not sure this is correct though as would the rf reciever mix with crystal meaning that the two signals would end up being forced into the same phase?